RNA recognition motif 1 (RRM1) found in cytoplasmic polyadenylation element-binding protein CPEB-2, CPEB-3, CPEB-4 and similar protiens; This subgroup corresponds to the RRM1 of the paralog proteins CPEB-2, CPEB-3 and CPEB-4, all well-conserved in both, vertebrates and invertebrates. Due to the high sequence similarity, members in this family may share similar expression patterns and functions. CPEB-2 is an RNA-binding protein that is abundantly expressed in testis and localized in cytoplasm in transfected HeLa cells. It preferentially binds to poly(U) RNA oligomers and may regulate the translation of stored mRNAs during spermiogenesis. Moreover, CPEB-2 impedes target RNA translation at elongation; it directly interacts with the elongation factor, eEF2, to reduce eEF2/ribosome-activated GTP hydrolysis in vitro and inhibit peptide elongation of CPEB2-bound RNA in vivo. CPEB-3 is a sequence-specific translational regulatory protein that regulates translation in a polyadenylation-independent manner. It functions as a translational repressor that governs the synthesis of the AMPA receptor GluR2 through binding GluR2 mRNA. It also represses translation of a reporter RNA in transfected neurons and stimulates translation in response to NMDA. CPEB-4 is an RNA-binding protein that mediates meiotic mRNA cytoplasmic polyadenylation and translation. It is essential for neuron survival and present on the endoplasmic reticulum (ER). It is accumulated in the nucleus upon ischemia or the depletion of ER calcium. CPEB-4 is overexpressed in a large variety of tumors and is associated with many mRNAs in cancer cells. All family members contain an N-terminal unstructured region, two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a Zn-finger motif. In addition, they do have conserved nuclear export signals that are not present in CPEB-1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPPKGYAFLLFQEESSVQALIDACIEEDGKLYLCVSSPTI 285
Cdd:cd12724     1 RKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPPKGYAFLLFQDERSVQALIDACIEEDDKLYLCVSSPTI 80

                          90
                  ....*....|..
gi 1034638407 286 KDKPVQIRPWNL 297
Cdd:cd12724    81 KDKPVQIRPWNL 92

Cytoplasmic polyadenylation element-binding protein ZZ domain; This ZZ-type zinc finger domain binds zinc via two conserved histidines in the C-terminal part of the domain.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034638407 389 VEVKPYVLDDqMCDECQGARcggkfAPFFCANVTCLQYYCEFCWANIHSRAGREFHKPLVKE 450
Cdd:pfam16366   1 VQIDPYLEDS-LCSECNGQP-----GPYFCRDLSCFKYYCRSCWQWQHSRDRLRNHKPLVRN 56

RNA recognition motif 1 (RRM1) found in cytoplasmic polyadenylation element-binding protein CPEB-2, CPEB-3, CPEB-4 and similar protiens; This subgroup corresponds to the RRM1 of the paralog proteins CPEB-2, CPEB-3 and CPEB-4, all well-conserved in both, vertebrates and invertebrates. Due to the high sequence similarity, members in this family may share similar expression patterns and functions. CPEB-2 is an RNA-binding protein that is abundantly expressed in testis and localized in cytoplasm in transfected HeLa cells. It preferentially binds to poly(U) RNA oligomers and may regulate the translation of stored mRNAs during spermiogenesis. Moreover, CPEB-2 impedes target RNA translation at elongation; it directly interacts with the elongation factor, eEF2, to reduce eEF2/ribosome-activated GTP hydrolysis in vitro and inhibit peptide elongation of CPEB2-bound RNA in vivo. CPEB-3 is a sequence-specific translational regulatory protein that regulates translation in a polyadenylation-independent manner. It functions as a translational repressor that governs the synthesis of the AMPA receptor GluR2 through binding GluR2 mRNA. It also represses translation of a reporter RNA in transfected neurons and stimulates translation in response to NMDA. CPEB-4 is an RNA-binding protein that mediates meiotic mRNA cytoplasmic polyadenylation and translation. It is essential for neuron survival and present on the endoplasmic reticulum (ER). It is accumulated in the nucleus upon ischemia or the depletion of ER calcium. CPEB-4 is overexpressed in a large variety of tumors and is associated with many mRNAs in cancer cells. All family members contain an N-terminal unstructured region, two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a Zn-finger motif. In addition, they do have conserved nuclear export signals that are not present in CPEB-1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPPKGYAFLLFQEESSVQALIDACIEEDGKLYLCVSSPTI 285
Cdd:cd12724     1 RKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPPKGYAFLLFQDERSVQALIDACIEEDDKLYLCVSSPTI 80

                          90
                  ....*....|..
gi 1034638407 286 KDKPVQIRPWNL 297
Cdd:cd12724    81 KDKPVQIRPWNL 92

RNA recognition motif;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 205 SRKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPP-KGYAFLLFQEESSVQALIDACIEEDGKLYLCVSSP 283
Cdd:pfam16367   1 SRKVFVGGLPWDITEAELTATFGRFGPLLVDWPGKPESPSYFPDvKGYVFLVFEDEKSVQALLDACTQEDGKYYLKLSSP 80

                          90
                  ....*....|.
gi 1034638407 284 TIKDKPVQIRP 294
Cdd:pfam16367  81 RMKDKPVQIRP 91

RNA recognition motif;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1034638407  207 KVFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSVQALIDAC 269
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVEsVRLVRDKETGK---SKGFAFVEFESEEDAEKALEAL 61

B-box-type 1 zinc finger (Bbox1); The B-box-type zinc finger is a short zinc binding domain of around 40 amino acid residues in length. It has been found in transcription factors, ribonucleoproteins and proto-oncoproteins, such as in TRIM (tripartite motif) proteins that consist of an N-terminal RING finger (originally called an A-box), followed by 1-2 B-box domains and a coiled-coil domain (also called RBCC for Ring, B-box, Coiled-Coil). The B-box-type zinc finger often presents in combination with other motifs, like RING zinc finger, NHL motif, coiled-coil or RFP domain, in functionally unrelated proteins, most likely mediating protein-protein interactions. Based on different consensus sequences and the spacing of the 7-8 zinc-binding residues, the B-box-type zinc fingers can be divided into two groups, type 1 (Bbox1: C6H2) and type 2 (Bbox2: CHC3H2). This family corresponds to the type 1 B-box (Bbox1).

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 1034638407 400 MCDECQGARcggkfAPFFCanVTCLQYYCEFCWANIHSR 438
Cdd:cd19757     1 LCDECEERE-----ATVYC--LECEEFLCDDCSDAIHRR 32

RNA recognition motif 1 (RRM1) found in cytoplasmic polyadenylation element-binding protein CPEB-2, CPEB-3, CPEB-4 and similar protiens; This subgroup corresponds to the RRM1 of the paralog proteins CPEB-2, CPEB-3 and CPEB-4, all well-conserved in both, vertebrates and invertebrates. Due to the high sequence similarity, members in this family may share similar expression patterns and functions. CPEB-2 is an RNA-binding protein that is abundantly expressed in testis and localized in cytoplasm in transfected HeLa cells. It preferentially binds to poly(U) RNA oligomers and may regulate the translation of stored mRNAs during spermiogenesis. Moreover, CPEB-2 impedes target RNA translation at elongation; it directly interacts with the elongation factor, eEF2, to reduce eEF2/ribosome-activated GTP hydrolysis in vitro and inhibit peptide elongation of CPEB2-bound RNA in vivo. CPEB-3 is a sequence-specific translational regulatory protein that regulates translation in a polyadenylation-independent manner. It functions as a translational repressor that governs the synthesis of the AMPA receptor GluR2 through binding GluR2 mRNA. It also represses translation of a reporter RNA in transfected neurons and stimulates translation in response to NMDA. CPEB-4 is an RNA-binding protein that mediates meiotic mRNA cytoplasmic polyadenylation and translation. It is essential for neuron survival and present on the endoplasmic reticulum (ER). It is accumulated in the nucleus upon ischemia or the depletion of ER calcium. CPEB-4 is overexpressed in a large variety of tumors and is associated with many mRNAs in cancer cells. All family members contain an N-terminal unstructured region, two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a Zn-finger motif. In addition, they do have conserved nuclear export signals that are not present in CPEB-1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPPKGYAFLLFQEESSVQALIDACIEEDGKLYLCVSSPTI 285
Cdd:cd12724     1 RKVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAESKSYFPPKGYAFLLFQDERSVQALIDACIEEDDKLYLCVSSPTI 80

                          90
                  ....*....|..
gi 1034638407 286 KDKPVQIRPWNL 297
Cdd:cd12724    81 KDKPVQIRPWNL 92

RNA recognition motif 2 (RRM2) found in cytoplasmic polyadenylation element-binding protein CPEB-2, CPEB-3, CPEB-4 and similar protiens; This subgroup corresponds to the RRM2 of the paralog proteins CPEB-2, CPEB-3 and CPEB-4, all well conserved in both, vertebrates and invertebrates. Due to the high sequence similarity, members in this family may share similar expression patterns and functions. CPEB-2 is an RNA-binding protein that is abundantly expressed in testis and localized in cytoplasm in transfected HeLa cells. It preferentially binds to poly(U) RNA oligomers and may regulate the translation of stored mRNAs during spermiogenesis. Moreover, CPEB-2 impedes target RNA translation at elongation; it directly interacts with the elongation factor, eEF2, to reduce eEF2/ribosome-activated GTP hydrolysis in vitro and inhibit peptide elongation of CPEB2-bound RNA in vivo. CPEB-3 is a sequence-specific translational regulatory protein that regulates translation in a polyadenylation-independent manner. It functions as a translational repressor that governs the synthesis of the AMPA receptor GluR2 through binding GluR2 mRNA. It also represses translation of a reporter RNA in transfected neurons and stimulates translation in response to NMDA. CPEB-4 is an RNA-binding protein that mediates meiotic mRNA cytoplasmic polyadenylation and translation. It is essential for neuron survival and present on the endoplasmic reticulum (ER). It is accumulated in the nucleus upon ischemia or the depletion of ER calcium. CPEB-4 is overexpressed in a large variety of tumors and is associated with many mRNAs in cancer cells. All family members contain an N-terminal unstructured region, two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a Zn-finger motif. In addition, they do have conserved nuclear export signals that are not present in CPEB-1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 314 KTIFVGGVPRPLRAVELAMIMDRLYGGVCYAGIDTDPELKYPKGAGRVAFSNQQSYIAAISARFVQLQHGDIDKRVEVKP 393
Cdd:cd12726     1 KTIFVGGVPRPLRAVELAMIMDRLYGGVCYAGIDTDPELKYPKGAGRVAFSNQQSYIAAISARFVQLQHGDIDKRVEVKP 80

                  .
gi 1034638407 394 Y 394
Cdd:cd12726    81 Y 81

RNA recognition motif 2 (RRM2) found in cytoplasmic polyadenylation element-binding protein CPEB-1, CPEB-2, CPEB-3, CPEB-4 and similar protiens; This subfamily corresponds to the RRM2 of CPEB family of proteins that bind to defined groups of mRNAs and act as either translational repressors or activators to regulate their translation. CPEB proteins are well conserved in both, vertebrates and invertebrates. Based on sequence similarity, RNA-binding specificity, and functional regulation of translation, the CPEB proteins has been classified into two subfamilies. The first subfamily includes CPEB-1 and related proteins. CPEB-1 is an RNA-binding protein that interacts with the cytoplasmic polyadenylation element (CPE), a short U-rich motif in the 3' untranslated regions (UTRs) of certain mRNAs. It functions as a translational regulator that plays a major role in the control of maternal CPE-containing mRNA in oocytes, as well as of subsynaptic CPE-containing mRNA in neurons. Once phosphorylated and recruiting the polyadenylation complex, CPEB-1 may function as a translational activator stimulating polyadenylation and translation. Otherwise, it may function as a translational inhibitor when dephosphorylated and bound to a protein such as maskin or neuroguidin, which blocks translation initiation through interfering with the assembly of eIF-4E and eIF-4G. Although CPEB-1 is mainly located in cytoplasm, it can shuttle between nucleus and cytoplasm. The second subfamily includes CPEB-2, CPEB-3, CPEB-4, and related protiens. Due to the high sequence similarity, members in this subfamily may share similar expression patterns and functions. CPEB-2 is an RNA-binding protein that is abundantly expressed in testis and localized in cytoplasm in transfected HeLa cells. It preferentially binds to poly(U) RNA oligomers and may regulate the translation of stored mRNAs during spermiogenesis. Moreover, CPEB-2 impedes target RNA translation at elongation. It directly interacts with the elongation factor, eEF2, to reduce eEF2/ribosome-activated GTP hydrolysis in vitro and inhibit peptide elongation of CPEB2-bound RNA in vivo. CPEB-3 is a sequence-specific translational regulatory protein that regulates translation in a polyadenylation-independent manner. It functions as a translational repressor that governs the synthesis of the AMPA receptor GluR2 through binding GluR2 mRNA. It also represses translation of a reporter RNA in transfected neurons and stimulates translation in response to NMDA. CPEB-4 is an RNA-binding protein that mediates meiotic mRNA cytoplasmic polyadenylation and translation. It is essential for neuron survival and present on the endoplasmic reticulum (ER). It is accumulated in the nucleus upon ischemia or the depletion of ER calcium. CPEB-4 is overexpressed in a large variety of tumors and is associated with many mRNAs in cancer cells. All CPEB proteins are nucleus-cytoplasm shuttling proteins. They contain an N-terminal unstructured region, followed by two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a Zn-finger motif. CPEB-2, -3, and -4 have conserved nuclear export signals that are not present in CPEB-1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 314 KTIFVGGVPRPLRAVELAMIMDRLYGGVCYAGIDTDPELKYPKGAGRVAFSNQQSYIAAISARFVQLQHGDIDKRVEVKP 393
Cdd:cd12445     1 RTVFVGGLPLPLTAAELAAILERLYGGVCYVEIDTDEFYLYPTGCARVTFNNEQSYIKAVSEVFVELPFGTINKRVRIRP 80

                  .
gi 1034638407 394 Y 394
Cdd:cd12445    81 Y 81

RNA recognition motif 2 (RRM2) found in cytoplasmic polyadenylation element-binding protein 1 (CPEB-1) and similar proteins; This subgroup corresponds to the RRM2 of CPEB-1 (also termed CPE-BP1 or CEBP), an RNA-binding protein that interacts with the cytoplasmic polyadenylation element (CPE), a short U-rich motif in the 3' untranslated regions (UTRs) of certain mRNAs. It functions as a translational regulator that plays a major role in the control of maternal CPE-containing mRNA in oocytes, as well as of subsynaptic CPE-containing mRNA in neurons. Once phosphorylated and recruiting the polyadenylation complex, CPEB-1 may function as a translational activator stimulating polyadenylation and translation. Otherwise, it may function as a translational inhibitor when dephosphorylated and bound to a protein such as maskin or neuroguidin, which blocks translation initiation through interfering with the assembly of eIF-4E and eIF-4G. Although CPEB-1 is mainly located in cytoplasm, it can shuttle between nucleus and cytoplasm. CPEB-1 contains an N-terminal unstructured region, two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a Zn-finger motif. Both of the RRMs and the Zn finger are required for CPEB-1 to bind CPE. The N-terminal regulatory region may be responsible for CPEB-1 interacting with other proteins.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 311 DPRKTIFVGGVPRPLRAVELAMIMDRLYGGVCYAGIDTDpELKYPKGAGRVAFSNQQSYIAAISARFVQLQHGDIDKRVE 390
Cdd:cd12725     1 DPSKTVFVGALHGMLNAEGLANIMNDLFGGVVYAGIDTD-KHKYPIGSGRVTFNNQRSYMKAVNAAFVEIKTPKFTKKVQ 79

                  ....
gi 1034638407 391 VKPY 394
Cdd:cd12725    80 IDPY 83

RNA recognition motif;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1034638407  207 KVFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSVQALIDAC 269
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVEsVRLVRDKETGK---SKGFAFVEFESEEDAEKALEAL 61

RNA recognition motif. (a.k.a. RRM, RBD, or RNP domain); The RRM motif is probably diagnostic of an RNA binding protein. RRMs are found in a variety of RNA binding proteins, including various hnRNP proteins, proteins implicated in regulation of alternative splicing, and protein components of snRNPs. The motif also appears in a few single stranded DNA binding proteins. The RRM structure consists of four strands and two helices arranged in an alpha/beta sandwich, with a third helix present during RNA binding in some cases The C-terminal beta strand (4th strand) and final helix are hard to align and have been omitted in the SEED alignment The LA proteins have an N terminal rrm which is included in the seed. There is a second region towards the C terminus that has some features characteriztic of a rrm but does not appear to have the important structural core of a rrm. The LA proteins are one of the main autoantigens in Systemic lupus erythematosus (SLE), an autoimmune disease.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfppKGYAFLLFQEESSVQALIDACieeDGKLY 277
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKsIRLVRDETGRS----KGFAFVEFEDEEDAEKAIEAL---NGKEL 64

RNA recognition motif 2 (RRM2) found in Deleted in azoospermia-associated protein 1 (DAZAP1) and similar proteins; This subfamily corresponds to the RRM2 of DAZAP1 or DAZ-associated protein 1, also termed proline-rich RNA binding protein (Prrp), a multi-functional ubiquitous RNA-binding protein expressed most abundantly in the testis and essential for normal cell growth, development, and spermatogenesis. DAZAP1 is a shuttling protein whose acetylated is predominantly nuclear and the nonacetylated form is in cytoplasm. DAZAP1 also functions as a translational regulator that activates translation in an mRNA-specific manner. DAZAP1 was initially identified as a binding partner of Deleted in Azoospermia (DAZ). It also interacts with numerous hnRNPs, including hnRNP U, hnRNP U like-1, hnRNPA1, hnRNPA/B, and hnRNP D, suggesting DAZAP1 might associate and cooperate with hnRNP particles to regulate adenylate-uridylate-rich elements (AU-rich element or ARE)-containing mRNAs. DAZAP1 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal proline-rich domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1034638407 205 SRKVFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSV 262
Cdd:cd12327     2 SKKVFVGGIPHNCGETELRDYFKRYGVVTeVVMMYDAEKQR---SRGFGFITFEDEQSV 57

RNA recognition motif (RRM) found in ras GTPase-activating protein-binding protein G3BP1, G3BP2 and similar proteins; This subfamily corresponds to the RRM domain in the G3BP family of RNA-binding and SH3 domain-binding proteins. G3BP acts at the level of RNA metabolism in response to cell signaling, possibly as RNA transcript stabilizing factors or an RNase. Members include G3BP1, G3BP2 and similar proteins. These proteins associate directly with the SH3 domain of GTPase-activating protein (GAP), which functions as an inhibitor of Ras. They all contain an N-terminal nuclear transfer factor 2 (NTF2)-like domain, an acidic domain, a domain containing PXXP motif(s), an RNA recognition motif (RRM), and an Arg-Gly-rich region (RGG-rich region, or arginine methylation motif).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1034638407 205 SRKVFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKsyfPPKGYAFLLFQEESSVQALIDAC 269
Cdd:cd12229     3 NHQLFVGNLPHDITEDELKEFFSRFGNVLeLRINSKGGGG---RLPNFGFVVFDDPEAVQKILANK 65

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor 3 (SRSF3) and similar proteins; This subfamily corresponds to the RRM of two serine/arginine (SR) proteins, serine/arginine-rich splicing factor 3 (SRSF3) and serine/arginine-rich splicing factor 7 (SRSF7). SRSF3, also termed pre-mRNA-splicing factor SRp20, modulates alternative splicing by interacting with RNA cis-elements in a concentration- and cell differentiation-dependent manner. It is also involved in termination of transcription, alternative RNA polyadenylation, RNA export, and protein translation. SRSF3 is critical for cell proliferation, and tumor induction and maintenance. It can shuttle between the nucleus and cytoplasm. SRSF7, also termed splicing factor 9G8, plays a crucial role in both constitutive splicing and alternative splicing of many pre-mRNAs. Its localization and functions are tightly regulated by phosphorylation. SRSF7 is predominantly present in the nuclear and can shuttle between nucleus and cytoplasm. It cooperates with the export protein, Tap/NXF1, helps mRNA export to the cytoplasm, and enhances the expression of unspliced mRNA. Moreover, SRSF7 inhibits tau E10 inclusion through directly interacting with the proximal downstream intron of E10, a clustering region for frontotemporal dementia with Parkinsonism (FTDP) mutations. Both SRSF3 and SRSF7 contain a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal RS domain rich in serine-arginine dipeptides. The RRM domain is involved in RNA binding, and the RS domain has been implicated in protein shuttling and protein-protein interactions.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAesksyfpPKGYAFLLFQEESSVQaliDACIEEDGK 275
Cdd:cd12373     1 KVYVGNLGPRVTKRELEDAFEKYGPLRNVWVARN-------PPGFAFVEFEDPRDAE---DAVRALDGR 59

RNA recognition motif (RRM) found in cyclophilin-33 (Cyp33) and similar proteins; This subfamily corresponds to the RRM of Cyp33, also termed peptidyl-prolyl cis-trans isomerase E (PPIase E), or cyclophilin E, or rotamase E. Cyp33 is a nuclear RNA-binding cyclophilin with an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal PPIase domain. Cyp33 possesses RNA-binding activity and preferentially binds to polyribonucleotide polyA and polyU, but hardly to polyG and polyC. It binds specifically to mRNA, which can stimulate its PPIase activity. Moreover, Cyp33 interacts with the third plant homeodomain (PHD3) zinc finger cassette of the mixed lineage leukemia (MLL) proto-oncoprotein and a poly-A RNA sequence through its RRM domain. It further mediates downregulation of the expression of MLL target genes HOXC8, HOXA9, CDKN1B, and C-MYC, in a proline isomerase-dependent manner. Cyp33 also possesses a PPIase activity that catalyzes cis-trans isomerization of the peptide bond preceding a proline, which has been implicated in the stimulation of folding and conformational changes in folded and unfolded proteins. The PPIase activity can be inhibited by the immunosuppressive drug cyclosporin A.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSYfppKGYAFLLFQEESSVQALID 267
Cdd:cd12347     1 LYVGGLAEEVDEKVLHAAFIPFGDIVdIQIPLDYETEKH---RGFAFVEFEEAEDAAAAID 58

RNA recognition motif 2 (RRM2) found in granule-associated RNA binding proteins (p40-TIA-1 and TIAR), and yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1; This subfamily corresponds to the RRM3 of TIA-1, TIAR, and PUB1. Nucleolysin TIA-1 isoform p40 (p40-TIA-1 or TIA-1) and nucleolysin TIA-1-related protein (TIAR) are granule-associated RNA binding proteins involved in inducing apoptosis in cytotoxic lymphocyte (CTL) target cells. They share high sequence similarity and are expressed in a wide variety of cell types. TIA-1 can be phosphorylated by a serine/threonine kinase that is activated during Fas-mediated apoptosis.TIAR is mainly localized in the nucleus of hematopoietic and nonhematopoietic cells. It is translocated from the nucleus to the cytoplasm in response to exogenous triggers of apoptosis. Both TIA-1 and TIAR bind specifically to poly(A) but not to poly(C) homopolymers. They are composed of three N-terminal highly homologous RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a glutamine-rich C-terminal auxiliary domain containing a lysosome-targeting motif. TIA-1 and TIAR interact with RNAs containing short stretches of uridylates and their RRM2 can mediate the specific binding to uridylate-rich RNAs. The C-terminal auxiliary domain may be responsible for interacting with other proteins. In addition, TIA-1 and TIAR share a potential serine protease-cleavage site (Phe-Val-Arg) localized at the junction between their RNA binding domains and their C-terminal auxiliary domains. This subfamily also includes a yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1, termed ARS consensus-binding protein ACBP-60, or poly uridylate-binding protein, or poly(U)-binding protein, which has been identified as both a heterogeneous nuclear RNA-binding protein (hnRNP) and a cytoplasmic mRNA-binding protein (mRNP). It may be stably bound to a translationally inactive subpopulation of mRNAs within the cytoplasm. PUB1 is distributed in both, the nucleus and the cytoplasm, and binds to poly(A)+ RNA (mRNA or pre-mRNA). Although it is one of the major cellular proteins cross-linked by UV light to polyadenylated RNAs in vivo, PUB1 is nonessential for cell growth in yeast. PUB1 also binds to T-rich single stranded DNA (ssDNA); however, there is no strong evidence implicating PUB1 in the mechanism of DNA replication. PUB1 contains three RRMs, and a GAR motif (glycine and arginine rich stretch) that is located between RRM2 and RRM3.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLvvdwphkAESKsYFPPKGYAFLLFQ-EESSVQALI 266
Cdd:cd12354     3 VYVGNITKGLTEALLQQTFSPFGQI-------LEVR-VFPDKGYAFIRFDsHEAATHAIV 54

RNA recognition motif 2 (RRM2) found in heterogeneous nuclear ribonucleoprotein A/B (hnRNP A/B) and similar proteins; This subgroup corresponds to the RRM2 of hnRNP A/B, also termed APOBEC1-binding protein 1 (ABBP-1), an RNA unwinding protein with a high affinity for G- followed by U-rich regions. hnRNP A/B has also been identified as an APOBEC1-binding protein that interacts with apolipoprotein B (apoB) mRNA transcripts around the editing site and thus plays an important role in apoB mRNA editing. hnRNP A/B contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a long C-terminal glycine-rich domain that contains a potential ATP/GTP binding loop.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPL-VVDWPHKAESKSYfppKGYAFLLFQEESSVQALID 267
Cdd:cd12584     5 KKIFVGGLNPETTEEKIREYFGEFGEIeAIELPMDPKTNKR---RGFVFITFKEEDPVKKILE 64

RNA recognition motif 2 (RRM2) found in heterogeneous nuclear ribonucleoprotein D0 (hnRNP D0) and similar proteins; This subgroup corresponds to the RRM2 of hnRNP D0, also termed AU-rich element RNA-binding protein 1, a UUAG-specific nuclear RNA binding protein that may be involved in pre-mRNA splicing and telomere elongation. hnRNP D0 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), in the middle and an RGG box rich in glycine and arginine residues in the C-terminal part. Each of RRMs can bind solely to the UUAG sequence specifically.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPL-VVDWPHKAESKSYfppKGYAFLLFQEESSVQALID 267
Cdd:cd12583     1 KIFVGGLSPDTPEEKIREYFGAFGEVeSIELPMDNKTNKR---RGFCFITFKEEEPVKKIME 59

RNA recognition motif;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034638407  315 TIFVGGVPRPLRAVELAMIMDRlYGGVCYAGIDTDPELKYPKGAGRVAFSNQQSYIAAISA 375
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSK-FGKVESVRLVRDKETGKSKGFAFVEFESEEDAEKALEA 60

RNA recognition motif 2 (RRM2) found in heterogeneous nuclear ribonucleoprotein A0 (hnRNP A0) and similar proteins; This subgroup corresponds to the RRM2 of hnRNP A0, a low abundance hnRNP protein that has been implicated in mRNA stability in mammalian cells. It has been identified as the substrate for MAPKAP-K2 and may be involved in the lipopolysaccharide (LPS)-induced post-transcriptional regulation of tumor necrosis factor-alpha (TNF-alpha), cyclooxygenase 2 (COX-2) and macrophage inflammatory protein 2 (MIP-2). hnRNP A0 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a long glycine-rich region at the C-terminus.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPLvvdwpHKAE---SKSYFPPKGYAFLLFQEESSV 262
Cdd:cd12579     1 KLFVGGLKGDVGEGDLVEHFSQFGTV-----EKVEviaDKDTGKKRGFGFVYFEDHDSA 54

RNA recognition motif 2 (RRM2) found in Deleted in azoospermia-associated protein 1 (DAZAP1) and similar proteins; This subfamily corresponds to the RRM2 of DAZAP1 or DAZ-associated protein 1, also termed proline-rich RNA binding protein (Prrp), a multi-functional ubiquitous RNA-binding protein expressed most abundantly in the testis and essential for normal cell growth, development, and spermatogenesis. DAZAP1 is a shuttling protein whose acetylated is predominantly nuclear and the nonacetylated form is in cytoplasm. DAZAP1 also functions as a translational regulator that activates translation in an mRNA-specific manner. DAZAP1 was initially identified as a binding partner of Deleted in Azoospermia (DAZ). It also interacts with numerous hnRNPs, including hnRNP U, hnRNP U like-1, hnRNPA1, hnRNPA/B, and hnRNP D, suggesting DAZAP1 might associate and cooperate with hnRNP particles to regulate adenylate-uridylate-rich elements (AU-rich element or ARE)-containing mRNAs. DAZAP1 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal proline-rich domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1034638407 314 KTIFVGGVPRPLRAVELAMIMDRlYGGVCYAGIDTDPELKYPKGAGRVAFSNQQSYIAAISARFVQLQhgdiDKRVEVK 392
Cdd:cd12327     3 KKVFVGGIPHNCGETELRDYFKR-YGVVTEVVMMYDAEKQRSRGFGFITFEDEQSVDQAVNMHFHDIM----GKKVEVK 76

RNA recognition motif 1 (RRM1) found in La-related protein 7 (LARP7) and similar proteins; This subfamily corresponds to the RRM1 of LARP7, also termed La ribonucleoprotein domain family member 7, or P-TEFb-interaction protein for 7SK stability (PIP7S), an oligopyrimidine-binding protein that binds to the highly conserved 3'-terminal U-rich stretch (3' -UUU-OH) of 7SK RNA. LARP7 is a stable component of the 7SK small nuclear ribonucleoprotein (7SK snRNP). It intimately associates with all the nuclear 7SK and is required for 7SK stability. LARP7 also acts as a negative transcriptional regulator of cellular and viral polymerase II genes, acting by means of the 7SK snRNP system. It plays an essential role in the inhibition of positive transcription elongation factor b (P-TEFb)-dependent transcription, which has been linked to the global control of cell growth and tumorigenesis. LARP7 contains a La motif (LAM) and an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), at the N-terminal region, which mediates binding to the U-rich 3' terminus of 7SK RNA. LARP7 also carries another putative RRM domain at its C-terminus.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSVQALIDA 268
Cdd:cd12290     2 VYVELLPKNATHEWIEAVFSKYGEVVyVSIPRYKSTGD---PKGFAFIEFETSESAQKAVKH 60

B-box-type 1 zinc finger (Bbox1); The B-box-type zinc finger is a short zinc binding domain of around 40 amino acid residues in length. It has been found in transcription factors, ribonucleoproteins and proto-oncoproteins, such as in TRIM (tripartite motif) proteins that consist of an N-terminal RING finger (originally called an A-box), followed by 1-2 B-box domains and a coiled-coil domain (also called RBCC for Ring, B-box, Coiled-Coil). The B-box-type zinc finger often presents in combination with other motifs, like RING zinc finger, NHL motif, coiled-coil or RFP domain, in functionally unrelated proteins, most likely mediating protein-protein interactions. Based on different consensus sequences and the spacing of the 7-8 zinc-binding residues, the B-box-type zinc fingers can be divided into two groups, type 1 (Bbox1: C6H2) and type 2 (Bbox2: CHC3H2). This family corresponds to the type 1 B-box (Bbox1).

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 1034638407 400 MCDECQGARcggkfAPFFCanVTCLQYYCEFCWANIHSR 438
Cdd:cd19757     1 LCDECEERE-----ATVYC--LECEEFLCDDCSDAIHRR 32

RNA recognition motif 1 (RRM1) found in RNA-binding protein MRN1 and similar proteins; This subgroup corresponds to the RRM1 of MRN1, also termed multicopy suppressor of RSC-NHP6 synthetic lethality protein 1, or post-transcriptional regulator of 69 kDa,which is a RNA-binding protein found in yeast. Although its specific biological role remains unclear, MRN1 might be involved in translational regulation. Members in this family contain four copies of conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034638407 205 SRKVFVGGLPPDIDEDEITaSFRRFGPLvvdwphkaESKSYFPPKGYAFLLFQEESSVQALI-DACIE 271
Cdd:cd12520     1 SRTVYLGNLPPNTTVKELL-SHVRSGPI--------ENVRILPEKNCAFISFLDPSAATAFHsDAILK 59

RNA recognition motif 1 (RRM1) found in Arabidopsis thaliana phragmoplastin interacting protein 1 (PHIP1) and similar proteins; This subfamily corresponds to the RRM1 of PHIP1. A. thaliana PHIP1 and its homologs represent a novel class of plant-specific RNA-binding proteins that may play a unique role in the polarized mRNA transport to the vicinity of the cell plate. The family members consist of multiple functional domains, including a lysine-rich domain (KRD domain) that contains three nuclear localization motifs (KKKR/NK), two RNA recognition motifs (RRMs), and three CCHC-type zinc fingers. PHIP1 is a peripheral membrane protein and is localized at the cell plate during cytokinesis in plants. In addition to phragmoplastin, PHIP1 interacts with two Arabidopsis small GTP-binding proteins, Rop1 and Ran2. However, PHIP1 interacted only with the GTP-bound form of Rop1 but not the GDP-bound form. It also binds specifically to Ran2 mRNA.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSVQALIDACIEEDGKLYLCV 280
Cdd:cd12271     1 VYVGGIPYYSTEAEIRSYFSSCGEVRsVDLMRFPDSGN---FRGIAFITFKTEEAAKRALALDGEMLGNRFLKV 71

RNA recognition motif 2 (RRM2) found in U2 large nuclear ribonucleoprotein auxiliary factor U2AF 65 kDa subunit (U2AF65) and similar proteins; This subfamily corresponds to the RRM2 of U2AF65 and dU2AF50. U2AF65, also termed U2AF2, is the large subunit of U2 small nuclear ribonucleoprotein (snRNP) auxiliary factor (U2AF), which has been implicated in the recruitment of U2 snRNP to pre-mRNAs and is a highly conserved heterodimer composed of large and small subunits. U2AF65 specifically recognizes the intron polypyrimidine tract upstream of the 3' splice site and promotes binding of U2 snRNP to the pre-mRNA branchpoint. U2AF65 also plays an important role in the nuclear export of mRNA. It facilitates the formation of a messenger ribonucleoprotein export complex, containing both the NXF1 receptor and the RNA substrate. Moreover, U2AF65 interacts directly and specifically with expanded CAG RNA, and serves as an adaptor to link expanded CAG RNA to NXF1 for RNA export. U2AF65 contains an N-terminal RS domain rich in arginine and serine, followed by a proline-rich segment and three C-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The N-terminal RS domain stabilizes the interaction of U2 snRNP with the branch point (BP) by contacting the branch region, and further promotes base pair interactions between U2 snRNA and the BP. The proline-rich segment mediates protein-protein interactions with the RRM domain of the small U2AF subunit (U2AF35 or U2AF1). The RRM1 and RRM2 are sufficient for specific RNA binding, while RRM3 is responsible for protein-protein interactions. The family also includes Splicing factor U2AF 50 kDa subunit (dU2AF50), the Drosophila ortholog of U2AF65. dU2AF50 functions as an essential pre-mRNA splicing factor in flies. It associates with intronless mRNAs and plays a significant and unexpected role in the nuclear export of a large number of intronless mRNAs.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGP-----LVVDwPHKAESksyfppKGYAFLLFQEES 260
Cdd:cd12231     2 KLFIGGLPNYLNEDQVKELLQSFGKlkafnLVKD-SATGLS------KGYAFCEYVDDN 53

RNA recognition motif (RRM) found in vertebrate deleted in azoospermia-like (DAZL) proteins; This subgroup corresponds to the RRM of DAZL, also termed SPGY-like-autosomal, encoded by the autosomal homolog of DAZ gene, DAZL. It is ancestral to the deleted in azoospermia (DAZ) protein. DAZL is germ-cell-specific RNA-binding protein that contains a RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a DAZ motif, a protein-protein interaction domain. Although their specific biochemical functions remain to be investigated, DAZL proteins may interact with poly(A)-binding proteins (PABPs), and act as translational activators of specific mRNAs during gametogenesis.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLVvdwPHKAESKSYFPPKGYAFLLFQEESSVQALIDACIEEDGK 275
Cdd:cd12672     8 VFVGGIDIRMDENEIRSFFARYGSVK---EVKIITDRTGVSKGYGFVSFYDDVDIQKIVESQINFHGK 72

RNA recognition motif 2 (RRM2) found in yeast protein gar2 and similar proteins; This subfamily corresponds to the RRM2 of yeast protein gar2, a novel nucleolar protein required for 18S rRNA and 40S ribosomal subunit accumulation. It shares similar domain architecture with nucleolin from vertebrates and NSR1 from Saccharomyces cerevisiae. The highly phosphorylated N-terminal domain of gar2 is made up of highly acidic regions separated from each other by basic sequences, and contains multiple phosphorylation sites. The central domain of gar2 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The C-terminal RGG (or GAR) domain of gar2 is rich in glycine, arginine and phenylalanine residues.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSVQALIDA 268
Cdd:cd12448     1 LFVGNLPFSATQDALYEAFSQHGSIVsVRLPTDRETGQ---PKGFGYVDFSTIDSAEAAIDA 59

RNA recognition motif 3 (RRM3) found in yeast nucleolar protein 4 (Nop4p) and similar proteins; This subgroup corresponds to the RRM3 of Nop4p (also known as Nop77p), encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 205 SRKVFVGGLPPDIDEDEITASFRRFGPL-----VVDwphKAESKSyfppKGYAFLLFQEESSVqaliDACIEEDGKLYlc 279
Cdd:cd12676     1 GRTLFVRNLPFDATEDELYSHFSQFGPLkyarvVKD---PATGRS----KGTAFVKFKNKEDA----DNCLSAAPEAQ-- 67

                          90       100
                  ....*....|....*....|....*..
gi 1034638407 280 VSSPTIKDKPVQIRPWNLSdSDFVMDG 306
Cdd:cd12676    68 STSLLEKYSLEQDITDDVS-AKFTLDG 93

RNA recognition motif (RRM) found in heterogeneous nuclear ribonucleoprotein G (hnRNP G), Y chromosome RNA recognition motif 1 (hRBMY), testis-specific heterogeneous nuclear ribonucleoprotein G-T (hnRNP G-T) and similar proteins; This subfamily corresponds to the RRM domain of hnRNP G, also termed glycoprotein p43 or RBMX, an RNA-binding motif protein located on the X chromosome. It is expressed ubiquitously and has been implicated in the splicing control of several pre-mRNAs. Moreover, hnRNP G may function as a regulator of transcription for SREBP-1c and GnRH1. Research has shown that hnRNP G may also act as a tumor-suppressor since it upregulates the Txnip gene and promotes the fidelity of DNA end-joining activity. In addition, hnRNP G appears to play a critical role in proper neural development of zebrafish and frog embryos. The family also includes several paralogs of hnRNP G, such as hRBMY and hnRNP G-T (also termed RNA-binding motif protein, X-linked-like-2). Both, hRBMY and hnRNP G-T, are exclusively expressed in testis and critical for male fertility. Like hnRNP G, hRBMY and hnRNP G-T interact with factors implicated in the regulation of pre-mRNA splicing, such as hTra2-beta1 and T-STAR. Although members in this family share a high conserved N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), they appear to recognize different RNA targets. For instance, hRBMY interacts specifically with a stem-loop structure in which the loop is formed by the sequence CA/UCAA. In contrast, hnRNP G associates with single stranded RNA sequences containing a CCA/C motif. In addition to the RRM, hnRNP G contains a nascent transcripts targeting domain (NTD) in the middle region and a novel auxiliary RNA-binding domain (RBD) in its C-terminal region. The C-terminal RBD exhibits distinct RNA binding specificity, and would play a critical role in the regulation of alternative splicing by hnRNP G.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPL--VVDWPHKAESKSyfppKGYAFLLFqeESSVQALiDACIEEDGK 275
Cdd:cd12382     3 KLFIGGLNTETNEKALEAVFGKYGRIveVLLMKDRETNKS----RGFAFVTF--ESPADAK-DAARDMNGK 66

RNA recognition motif 1 (RRM1) found in the p54nrb/PSF/PSP1 family; This subfamily corresponds to the RRM1 of the p54nrb/PSF/PSP1 family, including 54 kDa nuclear RNA- and DNA-binding protein (p54nrb or NonO or NMT55), polypyrimidine tract-binding protein (PTB)-associated-splicing factor (PSF or POMp100), paraspeckle protein 1 (PSP1 or PSPC1), which are ubiquitously expressed and are conserved in vertebrates. p54nrb is a multi-functional protein involved in numerous nuclear processes including transcriptional regulation, splicing, DNA unwinding, nuclear retention of hyperedited double-stranded RNA, viral RNA processing, control of cell proliferation, and circadian rhythm maintenance. PSF is also a multi-functional protein that binds RNA, single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and many factors, and mediates diverse activities in the cell. PSP1 is a novel nucleolar factor that accumulates within a new nucleoplasmic compartment, termed paraspeckles, and diffusely distributes in the nucleoplasm. The cellular function of PSP1 remains unknown currently. This subfamily also includes some p54nrb/PSF/PSP1 homologs from invertebrate species, such as the Drosophila melanogaster gene no-ontransient A (nonA) encoding puff-specific protein Bj6 (also termed NONA) and Chironomus tentans hrp65 gene encoding protein Hrp65. D. melanogaster NONA is involved in eye development and behavior, and may play a role in circadian rhythm maintenance, similar to vertebrate p54nrb. C. tentans Hrp65 is a component of nuclear fibers associated with ribonucleoprotein particles in transit from the gene to the nuclear pore. All family members contain a DBHS domain (for Drosophila behavior, human splicing), which comprises two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a charged protein-protein interaction module. PSF has an additional large N-terminal domain that differentiates it from other family members.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPLVVDWPHKAesksyfppKGYAFLlfQEESSVQALIdACIEEDGKlylcvsspTIK 286
Cdd:cd12332     3 RLFVGNLPNDITEEEFKELFQKYGEVSEVFLNKG--------KGFGFI--RLDTRANAEA-AKAELDGT--------PRK 63

                  ....*..
gi 1034638407 287 DKPVQIR 293
Cdd:cd12332    64 GRQLRVR 70

RNA recognition motif 1 (RRM1) found in plant pre-mRNA-splicing factor SF2 and similar proteins; This subgroup corresponds to the RRM1 of SF2, also termed SR1 protein, a plant serine/arginine (SR)-rich phosphoprotein similar to the mammalian splicing factor SF2/ASF. It promotes splice site switching in mammalian nuclear extracts. SF2 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a C-terminal domain rich in proline, serine and lysine residues (PSK domain), a composition reminiscent of histones. This PSK domain harbors a putative phosphorylation site for the mitotic kinase cyclin/p34cdc2.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPLVvdwphKAESKSYFPPKGYAFLLFQEESSVQaliDACIEEDG 274
Cdd:cd12599     1 RVYVGNLPMDIREREVEDLFSKYGPVV-----SIDLKIPPRPPAYAFVEFEDARDAE---DAIRGRDG 60

RNA recognition motif (RRM) found in vertebrate RNA-binding protein 7 (RBM7); This subfamily corresponds to the RRM of RBM7, a ubiquitously expressed pre-mRNA splicing factor that enhances messenger RNA (mRNA) splicing in a cell-specific manner or in a certain developmental process, such as spermatogenesis. RBM7 interacts with splicing factors SAP145 (the spliceosomal splicing factor 3b subunit 2) and SRp20. It may play a more specific role in meiosis entry and progression. Together with additional testis-specific RNA-binding proteins, RBM7 may regulate the splicing of specific pre-mRNA species that are important in the meiotic cell cycle. RBM7 contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a region lacking known homology at the C-terminus.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKsyfpPKGYAFLLFQEESSV 262
Cdd:cd12592     2 RTLFVGNLDTKVTEELLFELFLQAGPVIkVKIPKDKDGK----PKQFAFVNFKHEVSV 55

RNA recognition motif (RRM) found in U1 small nuclear ribonucleoprotein 70 kDa (U1-70K) and similar proteins; This subfamily corresponds to the RRM of U1-70K, also termed snRNP70, a key component of the U1 snRNP complex, which is one of the key factors facilitating the splicing of pre-mRNA via interaction at the 5' splice site, and is involved in regulation of polyadenylation of some viral and cellular genes, enhancing or inhibiting efficient poly(A) site usage. U1-70K plays an essential role in targeting the U1 snRNP to the 5' splice site through protein-protein interactions with regulatory RNA-binding splicing factors, such as the RS protein ASF/SF2. Moreover, U1-70K protein can specifically bind to stem-loop I of the U1 small nuclear RNA (U1 snRNA) contained in the U1 snRNP complex. It also mediates the binding of U1C, another U1-specific protein, to the U1 snRNP complex. U1-70K contains a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by an adjacent glycine-rich region at the N-terminal half, and two serine/arginine-rich (SR) domains at the C-terminal half. The RRM is responsible for the binding of stem-loop I of U1 snRNA molecule. Additionally, the most prominent immunodominant region that can be recognized by auto-antibodies from autoimmune patients may be located within the RRM. The SR domains are involved in protein-protein interaction with SR proteins that mediate 5' splice site recognition. For instance, the first SR domain is necessary and sufficient for ASF/SF2 Binding. The family also includes Drosophila U1-70K that is an essential splicing factor required for viability in flies, but its SR domain is dispensable. The yeast U1-70k doesn't contain easily recognizable SR domains and shows low sequence similarity in the RRM region with other U1-70k proteins and therefore not included in this family. The RRM domain is dispensable for yeast U1-70K function.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034638407 209 FVGGLPPDIDEDEITASFRRFGP-----LVVDwphKAESKsyfpPKGYAFLLFQEESSVQALIDACieeDGK 275
Cdd:cd12236     5 FVARLSYDTTESKLRREFEKYGPikrvrLVRD---KKTGK----SRGYAFIEFEHERDMKAAYKHA---DGK 66

RNA recognition motif 1 (RRM1) found in heterogeneous nuclear ribonucleoprotein A/B (hnRNP A/B) and similar proteins; This subgroup corresponds to the RRM1 of hnRNP A/B, also termed APOBEC1-binding protein 1 (ABBP-1), which is an RNA unwinding protein with a high affinity for G- followed by U-rich regions. hnRNP A/B has also been identified as an APOBEC1-binding protein that interacts with apolipoprotein B (apoB) mRNA transcripts around the editing site and thus plays an important role in apoB mRNA editing. hnRNP A/B contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a long C-terminal glycine-rich domain that contains a potential ATP/GTP binding loop.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPlVVDWPHKAESKSYfPPKGYAFLLFQEESSVQALID 267
Cdd:cd12757     6 KMFVGGLSWDTSKKDLKDYFTKFGE-VVDCTIKMDPNTG-RSRGFGFILFKDAASVDKVLE 64

RNA recognition motif 2 (RRM2) found in splicing factor 3B subunit 4 (SF3B4) and similar proteins; This subfamily corresponds to the RRM2 of SF3B4, also termed pre-mRNA-splicing factor SF3b 49 kDa (SF3b50), or spliceosome-associated protein 49 (SAP 49). SF3B4 is a component of the multiprotein complex splicing factor 3b (SF3B), an integral part of the U2 small nuclear ribonucleoprotein (snRNP) and the U11/U12 di-snRNP. SF3B is essential for the accurate excision of introns from pre-messenger RNA, and is involved in the recognition of the pre-mRNA's branch site within the major and minor spliceosomes. SF3B4 functions to tether U2 snRNP with pre-mRNA at the branch site during spliceosome assembly. It is an evolutionarily highly conserved protein with orthologs across diverse species. SF3B4 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It binds directly to pre-mRNA and also interacts directly and highly specifically with another SF3B subunit called SAP 145.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGpLVVDWPHKAESKSYFPPKGYAFLLFQE-ESSvqaliDACIEEDGKLYLC 279
Cdd:cd12335     4 LFIGNLDPEVDEKLLYDTFSAFG-VILQTPKIMRDPDTGNSKGFGFVSFDSfEAS-----DAAIEAMNGQYLC 70

RNA recognition motif (RRM) superfamily; RRM, also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), is a highly abundant domain in eukaryotes found in proteins involved in post-transcriptional gene expression processes including mRNA and rRNA processing, RNA export, and RNA stability. This domain is 90 amino acids in length and consists of a four-stranded beta-sheet packed against two alpha-helices. RRM usually interacts with ssRNA, but is also known to interact with ssDNA as well as proteins. RRM binds a variable number of nucleotides, ranging from two to eight. The active site includes three aromatic side-chains located within the conserved RNP1 and RNP2 motifs of the domain. The RRM domain is found in a variety heterogeneous nuclear ribonucleoproteins (hnRNPs), proteins implicated in regulation of alternative splicing, and protein components of small nuclear ribonucleoproteins (snRNPs).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034638407 316 IFVGGVPRPLRAVELAMIMDRlYGGVCYAGIDTDPELKyPKGAGRVAFSNQQSYIAAISArfvqLQHGDID-KRVEVK 392
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSK-FGEVVSVRIVRDRDGK-SKGFAFVEFESPEDAEKALEA----LNGTELGgRPLKVS 72

RNA recognition motif 3 in fungal pre-messenger RNA splicing protein 24 (Prp24) and similar proteins; This subfamily corresponds to the RRM3 of Prp24, also termed U4/U6 snRNA-associated-splicing factor PRP24 (U4/U6 snRNP), an RNA-binding protein with four well conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It facilitates U6 RNA base-pairing with U4 RNA during spliceosome assembly. Prp24 specifically binds free U6 RNA primarily with RRMs 1 and 2 and facilitates pairing of U6 RNA bases with U4 RNA bases. Additionally, it may also be involved in dissociation of the U4/U6 complex during spliceosome activation.

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gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPL-VVDWPHKAESKSYFPPKGYAFLLFQEESSVQA 264
Cdd:cd12298     1 REIRVRNLDFELDEEALRGIFEKFGEIeSINIPKKQKNRKGRHNNGFAFVTFEDADSAES 60

RNA recognition motif 3 (RRM3) found in RNA-binding protein 19 (RBM19) and RNA recognition motif 2 found in multiple RNA-binding domain-containing protein 1 (MRD1); This subfamily corresponds to the RRM3 of RBM19 and RRM2 of MRD1. RBM19, also termed RNA-binding domain-1 (RBD-1), is a nucleolar protein conserved in eukaryotes involved in ribosome biogenesis by processing rRNA and is essential for preimplantation development. It has a unique domain organization containing 6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). MRD1 is encoded by a novel yeast gene MRD1 (multiple RNA-binding domain). It is well conserved in yeast and its homologs exist in all eukaryotes. MRD1 is present in the nucleolus and the nucleoplasm. It interacts with the 35 S precursor rRNA (pre-rRNA) and U3 small nucleolar RNAs (snoRNAs). It is essential for the initial processing at the A0-A2 cleavage sites in the 35 S pre-rRNA. MRD1 contains 5 conserved RRMs, which may play an important structural role in organizing specific rRNA processing events.

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gi 1034638407 207 KVFVGGLPPDIDEDEITASFRRFGPLV-VDWPHKAESKSyfpPKGYAFLLFQEESSVQAlidACIEEDGKLY 277
Cdd:cd12316     1 RLFVRNLPFTATEDELRELFEAFGKISeVHIPLDKQTKR---SKGFAFVLFVIPEDAVK---AYQELDGSIF 66

RNA recognition motif in ribosomal RNA-processing protein 7 homolog A (Rrp7A) and similar proteins; This subfamily corresponds to the RRM of Rrp7A, also termed gastric cancer antigen Zg14, a homolog of yeast ribosomal RNA-processing protein 7 (Rrp7p), and mainly found in Metazoa. Rrp7p is an essential yeast protein involved in pre-rRNA processing and ribosome assembly, and is speculated to be required for correct assembly of rpS27 into the pre-ribosomal particle. In contrast, the cellular function of Rrp7A remains unclear currently. Rrp7A harbors an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal Rrp7 domain.

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gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPLV-VDW---PHKAESKS-----YF---PPKGY--AFLLFQEESSVQALI 266
Cdd:cd12294     1 RTLFVLNVPPYCTEESLKRLFSRCGKVEsVELqekPGPAEKIDsktskFFnpqPIKGFkvAYVVFKKPSSLKAAL 75

RNA recognition motif 2 (RRM2) found in RNA-binding protein 34 (RBM34) and similar proteins; This subfamily corresponds to the RRM2 of RBM34, a putative RNA-binding protein containing two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). Although the function of RBM34 remains unclear currently, its RRM domains may participate in mRNA processing. RBM34 may act as an mRNA processing-related protein.

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gi 1034638407 208 VFVGGLPPDIDEDEITASFRRFGP-----LVVDwphkaesKSYFPPKGYAFLLFQEESSVQ 263
Cdd:cd12395     2 VFVGNLPFDIEEEELRKHFEDCGDveavrIVRD-------RETGIGKGFGYVLFKDKDSVD 55

RNA recognition motif 2 (RRM2) found in CUGBP Elav-like family member CELF-3, CELF-4, CELF-5, CELF-6 and similar proteins; This subgroup corresponds to the RRM2 of CELF-3, CELF-4, CELF-5, and CELF-6, all of which belong to the CUGBP1 and ETR-3-like factors (CELF) or BRUNOL (Bruno-like) family of RNA-binding proteins that display dual nuclear and cytoplasmic localizations and have been implicated in the regulation of pre-mRNA splicing and in the control of mRNA translation and deadenylation. CELF-3, expressed in brain and testis only, is also known as bruno-like protein 1 (BRUNOL-1), or CAG repeat protein 4, or CUG-BP- and ETR-3-like factor 3, or embryonic lethal abnormal vision (ELAV)-type RNA-binding protein 1 (ETR-1), or expanded repeat domain protein CAG/CTG 4, or trinucleotide repeat-containing gene 4 protein (TNRC4). It plays an important role in the pathogenesis of tauopathies. CELF-3 contains three highly conserved RNA recognition motifs (RRMs), also known as RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains): two consecutive RRMs (RRM1 and RRM2) situated in the N-terminal region followed by a linker region and the third RRM (RRM3) close to the C-terminus of the protein. The effect of CELF-3 on tau splicing is mediated mainly by the RNA-binding activity of RRM2. The divergent linker region might mediate the interaction of CELF-3 with other proteins regulating its activity or involved in target recognition. CELF-4, being highly expressed throughout the brain and in glandular tissues, moderately expressed in heart, skeletal muscle, and liver, is also known as bruno-like protein 4 (BRUNOL-4), or CUG-BP- and ETR-3-like factor 4. Like CELF-3, CELF-4 also contain three highly conserved RRMs. The splicing activation or repression activity of CELF-4 on some specific substrates is mediated by its RRM1/RRM2. On the other hand, both RRM1 and RRM2 of CELF-4 can activate cardiac troponin T (cTNT) exon 5 inclusion. CELF-5, expressed in brain, is also known as bruno-like protein 5 (BRUNOL-5), or CUG-BP- and ETR-3-like factor 5. Although its biological role remains unclear, CELF-5 shares same domain architecture with CELF-3. CELF-6, being strongly expressed in kidney, brain, and testis, is also known as bruno-like protein 6 (BRUNOL-6), or CUG-BP- and ETR-3-like factor 6. It activates exon inclusion of a cardiac troponin T minigene in transient transfection assays in a muscle-specific splicing enhancer (MSE)-dependent manner and can activate inclusion via multiple copies of a single element, MSE2. CELF-6 also promotes skipping of exon 11 of insulin receptor, a known target of CELF activity that is expressed in kidney. In addition to three highly conserved RRMs, CELF-6 also possesses numerous potential phosphorylation sites, a potential nuclear localization signal (NLS) at the C terminus, and an alanine-rich region within the divergent linker region.

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gi 1034638407 206 RKVFVGGLPPDIDEDEITASFRRFGPL----VVDWPHKAEsksyfppKGYAFLLFQEESSVQALIDA 268
Cdd:cd12635     2 RKLFVGMLGKQQSEDDVRRLFEPFGSIeectILRGPDGNS-------KGCAFVKFSSHAEAQAAINA 61