Selenocysteine tRNA 1 associated proteins; This entry represents the C-terminal region of Selenocysteine tRNA 1 associated proteins (Trnau1ap also known as Secp43). Family members found in Eukaryotes have been shown to serve an essential role in the synthesis of selenoproteins, which have critical functions in numerous biological processes. Selenium deficiency results in a variety of diseases, including cardiac disease. Trnau1ap proteins harbor RNA recognition motifs (RRM) pfam00076 and Tyr-rich region found in the C-terminal. The Tyr-rich region (amino acids 185-225) is conserved among several mammals, including human, chimp, dog, cattle, mouse and rat. Furthermore, constitutive deletion of exons corresponding to the Tyr-rich region in mouse resulted in embryonic lethality.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720409875  96 QWGYDQNTGSYSYSYPQYGYTQS-TMQTYEEVGDDALEDPAPQLDVTEANKEFMEQSEELYDALMDCHWQPLDTVSSEIP 174
Cdd:pfam17654  22 QWGYDQYNGYYSYSYPQYGYTPApTTQEAEQQDEDPLEDPNLELDVEELNKEFMERSEELYDALMNCHWQPLDSVTSEIP 101

Selenocysteine tRNA 1 associated proteins; This entry represents the C-terminal region of Selenocysteine tRNA 1 associated proteins (Trnau1ap also known as Secp43). Family members found in Eukaryotes have been shown to serve an essential role in the synthesis of selenoproteins, which have critical functions in numerous biological processes. Selenium deficiency results in a variety of diseases, including cardiac disease. Trnau1ap proteins harbor RNA recognition motifs (RRM) pfam00076 and Tyr-rich region found in the C-terminal. The Tyr-rich region (amino acids 185-225) is conserved among several mammals, including human, chimp, dog, cattle, mouse and rat. Furthermore, constitutive deletion of exons corresponding to the Tyr-rich region in mouse resulted in embryonic lethality.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720409875  96 QWGYDQNTGSYSYSYPQYGYTQS-TMQTYEEVGDDALEDPAPQLDVTEANKEFMEQSEELYDALMDCHWQPLDTVSSEIP 174
Cdd:pfam17654  22 QWGYDQYNGYYSYSYPQYGYTPApTTQEAEQQDEDPLEDPNLELDVEELNKEFMERSEELYDALMNCHWQPLDSVTSEIP 101

polyadenylate binding protein, human types 1, 2, 3, 4 family; These eukaryotic proteins recognize the poly-A of mRNA and consists of four tandem RNA recognition domains at the N-terminus (rrm: pfam00076) followed by a PABP-specific domain (pfam00658) at the C-terminus. The protein is involved in the transport of mRNA's from the nucleus to the cytoplasm. There are four paralogs in Homo sapiens which are expressed in testis, platelets, broadly expressed and of unknown tissue range.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1720409875   1 MLYEFFvKVYPSCRGGKVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVgLGCKPVRLSVAIPKASR 69
Cdd:TIGR01628 301 KLRELF-SECGEITSAKVMLDEKGVSRGFGFVCFSNPEEANRAVTEMHGRM-LGGKPLYVALAQRKEQR 367

RNA recognition motif;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1720409875    1 MLYEFFVKvYPSCRGGKVVLDP-TGVSKGYGFVKFTDELEQKRALTECQGAVGLGcKPVRL 60
Cdd:smart00360  15 ELRELFSK-FGKVESVRLVRDKeTGKSKGFAFVEFESEEDAEKALEALNGKELDG-RPLKV 73

glycine-rich RNA-binding protein 4; Provisional

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1720409875  17 KVVLD-PTGVSKGYGFVKFTDELEQKRALTECQGAvGLGCKPVRLSVAIPKAS 68
Cdd:PLN03134   65 KVIVDrETGRSRGFGFVNFNDEGAATAAISEMDGK-ELNGRHIRVNPANDRPS 116

Selenocysteine tRNA 1 associated proteins; This entry represents the C-terminal region of Selenocysteine tRNA 1 associated proteins (Trnau1ap also known as Secp43). Family members found in Eukaryotes have been shown to serve an essential role in the synthesis of selenoproteins, which have critical functions in numerous biological processes. Selenium deficiency results in a variety of diseases, including cardiac disease. Trnau1ap proteins harbor RNA recognition motifs (RRM) pfam00076 and Tyr-rich region found in the C-terminal. The Tyr-rich region (amino acids 185-225) is conserved among several mammals, including human, chimp, dog, cattle, mouse and rat. Furthermore, constitutive deletion of exons corresponding to the Tyr-rich region in mouse resulted in embryonic lethality.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720409875  96 QWGYDQNTGSYSYSYPQYGYTQS-TMQTYEEVGDDALEDPAPQLDVTEANKEFMEQSEELYDALMDCHWQPLDTVSSEIP 174
Cdd:pfam17654  22 QWGYDQYNGYYSYSYPQYGYTPApTTQEAEQQDEDPLEDPNLELDVEELNKEFMERSEELYDALMNCHWQPLDSVTSEIP 101

RNA recognition motif 2 (RRM2) found in tRNA selenocysteine-associated protein 1 (SECp43) and similar proteins; This subfamily corresponds to the RRM2 in tRNA selenocysteine-associated protein 1 (SECp43), yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8, and similar proteins. SECp43 is an RNA-binding protein associated specifically with eukaryotic selenocysteine tRNA [tRNA(Sec)]. It may play an adaptor role in the mechanism of selenocysteine insertion. SECp43 is located primarily in the nucleus and contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal polar/acidic region. Yeast proteins, NGR1 and NAM8, show high sequence similarity with SECp43. NGR1 is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA). It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains three RRMs, two of which are followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the C-terminus which also harbors a methionine-rich region. NAM8 is a putative RNA-binding protein that acts as a suppressor of mitochondrial splicing deficiencies when overexpressed in yeast. It may be a non-essential component of the mitochondrial splicing machinery. NAM8 also contains three RRMs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1720409875   1 MLYEFFVKVYPSCRGGKVVLDP-TGVSKGYGFVKFTDELEQKRALTECQGaVGLGCKPVRLSVAI 64
Cdd:cd12345    17 QLYETFSARYPSVRGAKVVMDPvTGRSKGYGFVRFGDESEQDRALTEMQG-VYLGSRPIRVSPAT 80

RNA recognition motif (RRM) found in RNA-binding protein 42 (RBM42) and similar proteins; This subfamily corresponds to the RRM of RBM42 which has been identified as a heterogeneous nuclear ribonucleoprotein K (hnRNP K)-binding protein. It also directly binds the 3' untranslated region of p21 mRNA that is one of the target mRNAs for hnRNP K. Both, hnRNP K and RBM42, are components of stress granules (SGs). Under nonstress conditions, RBM42 predominantly localizes within the nucleus and co-localizes with hnRNP K. Under stress conditions, hnRNP K and RBM42 form cytoplasmic foci where the SG marker TIAR localizes, and may play a role in the maintenance of cellular ATP level by protecting their target mRNAs. RBM42 contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1720409875   1 MLYEFFVKvYPSCRGGKVVLDP-TGVSKGYGFVKFTDELEQKRALTECQGAVgLGCKPVRLS 61
Cdd:cd12383    22 VLARAFSK-YPSFQKAKVIRDKrTGKSKGYGFVSFKDPNDYLKALREMNGKY-VGNRPIKLR 81

polyadenylate binding protein, human types 1, 2, 3, 4 family; These eukaryotic proteins recognize the poly-A of mRNA and consists of four tandem RNA recognition domains at the N-terminus (rrm: pfam00076) followed by a PABP-specific domain (pfam00658) at the C-terminus. The protein is involved in the transport of mRNA's from the nucleus to the cytoplasm. There are four paralogs in Homo sapiens which are expressed in testis, platelets, broadly expressed and of unknown tissue range.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1720409875   1 MLYEFFvKVYPSCRGGKVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVgLGCKPVRLSVAIPKASR 69
Cdd:TIGR01628 301 KLRELF-SECGEITSAKVMLDEKGVSRGFGFVCFSNPEEANRAVTEMHGRM-LGGKPLYVALAQRKEQR 367

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1720409875   2 LYEFFVKVYP--SCRggkVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVgLGCKPVRLS 61
Cdd:cd00590    15 LRELFSKFGEvvSVR---IVRDRDGKSKGFAFVEFESPEDAEKALEALNGTE-LGGRPLKVS 72

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 1720409875   4 EFFVKvYPSCRGGKVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVGlgcKPVRLSVAIPK 66
Cdd:cd12672    24 SFFAR-YGSVKEVKIITDRTGVSKGYGFVSFYDDVDIQKIVESQINFHG---KKLKLGPAIRK 82

RNA recognition motif 1 (RRM1) found in yeast nucleolar protein 4 (Nop4p) and similar proteins; This subgroup corresponds to the RRM1 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
                  ....*....|....*....|....*....|....*....|....*...
gi 1720409875   2 LYEFFVKVYPsCRGGKVVLDP-TGVSKGYGFVKFTDELEQKRALTECQ 48
Cdd:cd12674    17 LTDFFSDIGP-VKHAVVVTDPeTKKSRGYGFVSFSTHDDAEEALAKLK 63

RNA recognition motif 2 (RRM2) found found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM2 of type I poly(A)-binding proteins (PABPs), highly conserved proteins that bind to the poly(A) tail present at the 3' ends of most eukaryotic mRNAs. They have been implicated in the regulation of poly(A) tail length during the polyadenylation reaction, translation initiation, mRNA stabilization by influencing the rate of deadenylation and inhibition of mRNA decapping. The family represents type I polyadenylate-binding proteins (PABPs), including polyadenylate-binding protein 1 (PABP-1 or PABPC1), polyadenylate-binding protein 3 (PABP-3 or PABPC3), polyadenylate-binding protein 4 (PABP-4 or APP-1 or iPABP), polyadenylate-binding protein 5 (PABP-5 or PABPC5), polyadenylate-binding protein 1-like (PABP-1-like or PABPC1L), polyadenylate-binding protein 1-like 2 (PABPC1L2 or RBM32), polyadenylate-binding protein 4-like (PABP-4-like or PABPC4L), yeast polyadenylate-binding protein, cytoplasmic and nuclear (PABP or ACBP-67), and similar proteins. PABP-1 is a ubiquitously expressed multifunctional protein that may play a role in 3' end formation of mRNA, translation initiation, mRNA stabilization, protection of poly(A) from nuclease activity, mRNA deadenylation, inhibition of mRNA decapping, and mRNP maturation. Although PABP-1 is thought to be a cytoplasmic protein, it is also found in the nucleus. PABP-1 may be involved in nucleocytoplasmic trafficking and utilization of mRNP particles. PABP-1 contains four copies of RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), a less well conserved linker region, and a proline-rich C-terminal conserved domain (CTD). PABP-3 is a testis-specific poly(A)-binding protein specifically expressed in round spermatids. It is mainly found in mammalian and may play an important role in the testis-specific regulation of mRNA homeostasis. PABP-3 shows significant sequence similarity to PABP-1. However, it binds to poly(A) with a lower affinity than PABP-1. Moreover, PABP-1 possesses an A-rich sequence in its 5'-UTR and allows binding of PABP and blockage of translation of its own mRNA. In contrast, PABP-3 lacks the A-rich sequence in its 5'-UTR. PABP-4 is an inducible poly(A)-binding protein (iPABP) that is primarily localized to the cytoplasm. It shows significant sequence similarity to PABP-1 as well. The RNA binding properties of PABP-1 and PABP-4 appear to be identical. PABP-5 is encoded by PABPC5 gene within the X-specific subinterval, and expressed in fetal brain and in a range of adult tissues in mammalian, such as ovary and testis. It may play an important role in germ cell development. Unlike other PABPs, PABP-5 contains only four RRMs, but lacks both the linker region and the CTD. PABP-1-like and PABP-1-like 2 are the orthologs of PABP-1. PABP-4-like is the ortholog of PABP-5. Their cellular functions remain unclear. The family also includes the yeast PABP, a conserved poly(A) binding protein containing poly(A) tails that can be attached to the 3'-ends of mRNAs. The yeast PABP and its homologs may play important roles in the initiation of translation and in mRNA decay. Like vertebrate PABP-1, the yeast PABP contains four RRMs, a linker region, and a proline-rich CTD as well. The first two RRMs are mainly responsible for specific binding to poly(A). The proline-rich region may be involved in protein-protein interactions.

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1720409875  12 SCrggKVVLDPTGVSKGYGFVKFTDELEQKRALTECQG 49
Cdd:cd12379    31 SC---KVATDENGGSKGYGFVHFETEEAAERAIEKVNG 65

polyadenylate binding protein, human types 1, 2, 3, 4 family; These eukaryotic proteins recognize the poly-A of mRNA and consists of four tandem RNA recognition domains at the N-terminus (rrm: pfam00076) followed by a PABP-specific domain (pfam00658) at the C-terminus. The protein is involved in the transport of mRNA's from the nucleus to the cytoplasm. There are four paralogs in Homo sapiens which are expressed in testis, platelets, broadly expressed and of unknown tissue range.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1720409875   2 LYEFFVKV--YPSCrggKVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVgLGCKPVRLSVAIPKASR-VKPVE 74
Cdd:TIGR01628 105 LFDTFSKFgnILSC---KVATDENGKSRGYGFVHFEKEESAKAAIQKVNGML-LNDKEVYVGRFIKKHEReAAPLK 176

RNA recognition motif 1 (RRM1) found in Saccharomyces cerevisiae protein PES4, protein MIP6 and similar proteins; The family includes PES4 (also called DNA polymerase epsilon suppressor 4) and MIP6 (also called MEX67-interacting protein 6), both of which are predicted RNA binding proteins that may act as regulators of late translation, protection, and mRNA localization. MIP6 acts as a novel factor for nuclear mRNA export, binds to both poly(A)+ RNA and nuclear pores. It interacts with MEX67. Members in this family contain four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the first RRM motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1720409875   1 MLYEFFvKVYPSCRGGKVVLDP-TGVSKGYGFVKFTDELEQKRALTE 46
Cdd:cd21601    16 MLRDIF-SKYKSLVSVKICLDSeTKKSLGYGYLNFSDKEDAEKAIEE 61

RNA recognition motif 2 (RRM2) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM2 of RBM28 and Nop4p. RBM28 is a specific nucleolar component of the spliceosomal small nuclear ribonucleoproteins (snRNPs), possibly coordinating their transition through the nucleolus. It specifically associates with U1, U2, U4, U5, and U6 small nuclear RNAs (snRNAs), and may play a role in the maturation of both small nuclear and ribosomal RNAs. RBM28 has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an extremely acidic region between RRM2 and RRM3. The family also includes nucleolar protein 4 (Nop4p or 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 also contains four RRMs.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 1720409875  17 KVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVGLGcKPVRLSVAI 64
Cdd:cd12414    30 TIPKKPDGKLRGFAFVQFTNVADAAKAIKGMNGKKIKG-RPVAVDWAV 76

RNA recognition motif (RRM) found in Saccharomyces cerevisiae U1 small nuclear ribonucleoprotein SNP1 and similar proteins; SNP1, also called U1 snRNP protein SNP1, or U1 small nuclear ribonucleoprotein 70 kDa homolog, or U1 70K, or U1 snRNP 70 kDa homolog, interacts with mRNA and is involved in nuclear mRNA splicing. It is a component of the spliceosome, where it is associated with snRNP U1 by binding stem loop I of U1 snRNA. Members in this family contain an N-terminal U1snRNP70 domain and an RNA recognition motif (RRM), also called RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1720409875  17 KVVLDP-TGVSKGYGFVKFTDELEQKRALTECQGAVGL 53
Cdd:cd21615    49 RIVRDKeTGKSRGYAFIVFKSESDAKNAFKEGNGLRGL 86

RNA recognition motif 2 (RRM2) found in Nicotiana sylvestris chloroplastic 33 kDa ribonucleoprotein (NsCP33) and similar proteins; The family includes NsCP33, Arabidopsis thaliana chloroplastic 31 kDa ribonucleoprotein (CP31A) and mitochondrial glycine-rich RNA-binding protein 2 (AtGR-RBP2). NsCP33 may be involved in splicing and/or processing of chloroplast RNA's. AtCP31A, also called RNA-binding protein 1/2/3 (AtRBP33), or RNA-binding protein CP31A, or RNA-binding protein RNP-T, or RNA-binding protein cp31, is required for specific RNA editing events in chloroplasts and stabilizes specific chloroplast mRNAs, as well as for normal chloroplast development under cold stress conditions by stabilizing transcripts of numerous mRNAs under these conditions. CP31A may modulate telomere replication through RNA binding domains. AtGR-RBP2, also called AtRBG2, or glycine-rich protein 2 (AtGRP2), or mitochondrial RNA-binding protein 1a (At-mRBP1a), plays a role in RNA transcription or processing during stress. It binds RNAs and DNAs sequence with a preference to single-stranded nucleic acids. AtGR-RBP2 displays strong affinity to poly(U) sequence. It exerts cold and freezing tolerance, probably by exhibiting an RNA chaperone activity during the cold and freezing adaptation process. Some members in this family contain two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the second RRM motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1720409875  16 GKVVLD-PTGVSKGYGFVKFTDELEQKRALTECQGAVgLGCKPVRLSVA 63
Cdd:cd21608    29 AKVITDrETGRSRGFGFVTFSTAEAAEAAIDALNGKE-LDGRSIVVNEA 76

RNA recognition motif (RRM) found in transformer-2 protein homolog TRA2-alpha, TRA2-beta and similar proteins; This subfamily corresponds to the RRM of two mammalian homologs of Drosophila transformer-2 (Tra2), TRA2-alpha, TRA2-beta (also termed SFRS10), and similar proteins found in eukaryotes. TRA2-alpha is a 40-kDa serine/arginine-rich (SR) protein that specifically binds to gonadotropin-releasing hormone (GnRH) exonic splicing enhancer on exon 4 (ESE4) and is necessary for enhanced GnRH pre-mRNA splicing. It strongly stimulates GnRH intron A excision in a dose-dependent manner. In addition, TRA2-alpha can interact with either 9G8 or SRp30c, which may also be crucial for ESE-dependent GnRH pre-mRNA splicing. TRA2-beta is a serine/arginine-rich (SR) protein that controls the pre-mRNA alternative splicing of the calcitonin/calcitonin gene-related peptide (CGRP), the survival motor neuron 1 (SMN1) protein and the tau protein. Both, TRA2-alpha and TRA2-beta, contains a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), flanked by the N- and C-terminal arginine/serine (RS)-rich regions.

                          10        20        30
                  ....*....|....*....|....*....|....
gi 1720409875  17 KVVLD-PTGVSKGYGFVKFTDELEQKRALTECQG 49
Cdd:cd12363    32 QVVYDqQTGRSRGFGFVYFESVEDAKEAKERLNG 65

RNA recognition motif (RRM) found in heterogeneous nuclear ribonucleoprotein (hnRNP) H protein family, epithelial splicing regulatory proteins (ESRPs), Drosophila RNA-binding protein Fusilli, RNA-binding protein 12 (RBM12) and similar proteins; The family includes RRM domains in the hnRNP H protein family, G-rich sequence factor 1 (GRSF-1), ESRPs (also termed RBM35), Drosophila Fusilli, RBM12 (also termed SWAN), RBM12B, RBM19 (also termed RBD-1) and similar proteins. The hnRNP H protein family includes hnRNP H (also termed mcs94-1), hnRNP H2 (also termed FTP-3 or hnRNP H'), hnRNP F and hnRNP H3 (also termed hnRNP 2H9), which represent a group of nuclear RNA binding proteins that are involved in pre-mRNA processing. GRSF-1 is a cytoplasmic poly(A)+ mRNA binding protein which interacts with RNA in a G-rich element-dependent manner. It may function in RNA packaging, stabilization of RNA secondary structure, or other macromolecular interactions. ESRP1 (also termed RBM35A) and ESRP2 (also termed RBM35B) are epithelial-specific RNA binding proteins that promote splicing of the epithelial variant of fibroblast growth factor receptor 2 (FGFR2), ENAH (also termed hMena), CD44 and CTNND1 (also termed p120-Catenin) transcripts. Fusilli shows high sequence homology to ESRPs. It can regulate endogenous FGFR2 splicing and functions as a splicing factor. The biological roles of both, RBM12 and RBM12B, remain unclear. RBM19 is a nucleolar protein conserved in eukaryotes. It is involved in ribosome biogenesis by processing rRNA. In addition, it is essential for preimplantation development. Members in this family contain 2~6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1720409875   3 YEFFVKVYPSCRGGKVVLDPTGVSKGYGFVKFTDELEQKRALTECQGAVG 52
Cdd:cd12254    17 RDFFSGLDIPPDGIHIVYDDDGRPTGEAYVEFASEEDAQRALRRHKGKMG 66

RNA recognition motif 2 (RRM2) found in nucleolysin TIAR and similar proteins; This subgroup corresponds to the RRM2 of nucleolysin TIAR, also termed TIA-1-related protein, a cytotoxic granule-associated RNA-binding protein that shows high sequence similarity with 40-kDa isoform of T-cell-restricted intracellular antigen-1 (p40-TIA-1). 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. TIAR possesses nucleolytic activity against cytolytic lymphocyte (CTL) target cells. It can trigger DNA fragmentation in permeabilized thymocytes, and thus may function as an effector responsible for inducing apoptosis. TIAR is 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. It interacts with RNAs containing short stretches of uridylates and its RRM2 can mediate the specific binding to uridylate-rich RNAs.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1720409875  16 GKVVLD-PTGVSKGYGFVKFTDELEQKRALTEcQGAVGLGCKPVRLSVA 63
Cdd:cd12617    31 ARVVKDmATGKSKGYGFVSFYNKLDAENAIVH-MGGQWLGGRQIRTNWA 78

RNA recognition motif 1 (RRM1) found in the Hu proteins family, Drosophila sex-lethal (SXL), and similar proteins; This subfamily corresponds to the RRM1 of Hu proteins and SXL. The Hu proteins family represents a group of RNA-binding proteins involved in diverse biological processes. Since the Hu proteins share high homology with the Drosophila embryonic lethal abnormal vision (ELAV) protein, the Hu family is sometimes referred to as the ELAV family. Drosophila ELAV is exclusively expressed in neurons and is required for the correct differentiation and survival of neurons in flies. The neuronal members of the Hu family include Hu-antigen B (HuB or ELAV-2 or Hel-N1), Hu-antigen C (HuC or ELAV-3 or PLE21), and Hu-antigen D (HuD or ELAV-4), which play important roles in neuronal differentiation, plasticity and memory. HuB is also expressed in gonads. Hu-antigen R (HuR or ELAV-1 or HuA) is ubiquitously expressed Hu family member. It has a variety of biological functions mostly related to the regulation of cellular response to DNA damage and other types of stress. Hu proteins perform their cytoplasmic and nuclear molecular functions by coordinately regulating functionally related mRNAs. In the cytoplasm, Hu proteins recognize and bind to AU-rich RNA elements (AREs) in the 3' untranslated regions (UTRs) of certain target mRNAs, such as GAP-43, vascular epithelial growth factor (VEGF), the glucose transporter GLUT1, eotaxin and c-fos, and stabilize those ARE-containing mRNAs. They also bind and regulate the translation of some target mRNAs, such as neurofilament M, GLUT1, and p27. In the nucleus, Hu proteins function as regulators of polyadenylation and alternative splicing. Each Hu protein contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). RRM1 and RRM2 may cooperate in binding to an ARE. RRM3 may help to maintain the stability of the RNA-protein complex, and might also bind to poly(A) tails or be involved in protein-protein interactions. This family also includes the sex-lethal protein (SXL) from Drosophila melanogaster. SXL governs sexual differentiation and X chromosome dosage compensation in flies. It induces female-specific alternative splicing of the transformer (tra) pre-mRNA by binding to the tra uridine-rich polypyrimidine tract at the non-sex-specific 3' splice site during the sex-determination process. SXL binds to its own pre-mRNA and promotes female-specific alternative splicing. It contains an N-terminal Gly/Asn-rich domain that may be responsible for the protein-protein interaction, and tandem RRMs that show high preference to bind single-stranded, uridine-rich target RNA transcripts.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1720409875   2 LYEFFVKVYP--SCrggKVVLDP-TGVSKGYGFVKFTDELEQKRALTECQGaVGLGCKPVRLSVA 63
Cdd:cd12375    16 LRSLFGAIGPieSC---KLVRDKiTGQSLGYGFVNYRDPNDARKAINTLNG-LDLENKRLKVSYA 76

RNA recognition motif 3 (RRM3) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM3 of RBM28 and Nop4p. RBM28 is a specific nucleolar component of the spliceosomal small nuclear ribonucleoproteins (snRNPs), possibly coordinating their transition through the nucleolus. It specifically associates with U1, U2, U4, U5, and U6 small nuclear RNAs (snRNAs), and may play a role in the maturation of both small nuclear and ribosomal RNAs. RBM28 has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an extremely acidic region between RRM2 and RRM3. The family also includes nucleolar protein 4 (Nop4p or 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 also contains four RRMs.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1720409875   2 LYEFFVKvYPSCRGGKVVLDP-TGVSKGYGFVKFTD 36
Cdd:cd12415    17 LKEFFSK-FGEVKYARIVLDKdTGHSKGTAFVQFKT 51

RNA recognition motif 2 (RRM2) found in the Hu proteins family; This subfamily corresponds to the RRM2 of Hu proteins family which represents a group of RNA-binding proteins involved in diverse biological processes. Since the Hu proteins share high homology with the Drosophila embryonic lethal abnormal vision (ELAV) protein, the Hu family is sometimes referred to as the ELAV family. Drosophila ELAV is exclusively expressed in neurons and is required for the correct differentiation and survival of neurons in flies. The neuronal members of the Hu family include Hu-antigen B (HuB or ELAV-2 or Hel-N1), Hu-antigen C (HuC or ELAV-3 or PLE21), and Hu-antigen D (HuD or ELAV-4), which play important roles in neuronal differentiation, plasticity and memory. HuB is also expressed in gonads. Hu-antigen R (HuR or ELAV-1 or HuA) is the ubiquitously expressed Hu family member. It has a variety of biological functions mostly related to the regulation of cellular response to DNA damage and other types of stress. Moreover, HuR has an anti-apoptotic function during early cell stress response. It binds to mRNAs and enhances the expression of several anti-apoptotic proteins, such as p21waf1, p53, and prothymosin alpha. HuR also has pro-apoptotic function by promoting apoptosis when cell death is unavoidable. Furthermore, HuR may be important in muscle differentiation, adipogenesis, suppression of inflammatory response and modulation of gene expression in response to chronic ethanol exposure and amino acid starvation. Hu proteins perform their cytoplasmic and nuclear molecular functions by coordinately regulating functionally related mRNAs. In the cytoplasm, Hu proteins recognize and bind to AU-rich RNA elements (AREs) in the 3' untranslated regions (UTRs) of certain target mRNAs, such as GAP-43, vascular epithelial growth factor (VEGF), the glucose transporter GLUT1, eotaxin and c-fos, and stabilize those ARE-containing mRNAs. They also bind and regulate the translation of some target mRNAs, such as neurofilament M, GLUT1, and p27. In the nucleus, Hu proteins function as regulators of polyadenylation and alternative splicing. Each Hu protein contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). RRM1 and RRM2 may cooperate in binding to an ARE. RRM3 may help to maintain the stability of the RNA-protein complex, and might also bind to poly(A) tails or be involved in protein-protein interactions.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1720409875  17 KVVLDP-TGVSKGYGFVKFTDELEQKRALTECQGAVGLGC 55
Cdd:cd12652    31 RILCDNvTGLSRGVGFIRFDKRVEAERAIKALNGTIPPGA 70

RNA recognition motif (RRM) found in cleavage stimulation factor subunit 2 (CSTF2), yeast ortholog mRNA 3'-end-processing protein RNA15 and similar proteins; This subfamily corresponds to the RRM domain of CSTF2, its tau variant and eukaryotic homologs. CSTF2, also termed cleavage stimulation factor 64 kDa subunit (CstF64), is the vertebrate conterpart of yeast mRNA 3'-end-processing protein RNA15. It is expressed in all somatic tissues and is one of three cleavage stimulatory factor (CstF) subunits required for polyadenylation. CstF64 contains an N-terminal RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a CstF77-binding domain, a repeated MEARA helical region and a conserved C-terminal domain reported to bind the transcription factor PC-4. During polyadenylation, CstF interacts with the pre-mRNA through the RRM of CstF64 at U- or GU-rich sequences within 10 to 30 nucleotides downstream of the cleavage site. CSTF2T, also termed tauCstF64, is a paralog of the X-linked cleavage stimulation factor CstF64 protein that supports polyadenylation in most somatic cells. It is expressed during meiosis and subsequent haploid differentiation in a more limited set of tissues and cell types, largely in meiotic and postmeiotic male germ cells, and to a lesser extent in brain. The loss of CSTF2T will cause male infertility, as it is necessary for spermatogenesis and fertilization. Moreover, CSTF2T is required for expression of genes involved in morphological differentiation of spermatids, as well as for genes having products that function during interaction of motile spermatozoa with eggs. It promotes germ cell-specific patterns of polyadenylation by using its RRM to bind to different sequence elements downstream of polyadenylation sites than does CstF64. The family also includes yeast ortholog mRNA 3'-end-processing protein RNA15 and similar proteins. RNA15 is a core subunit of cleavage factor IA (CFIA), an essential transcriptional 3'-end processing factor from Saccharomyces cerevisiae. RNA recognition by CFIA is mediated by an N-terminal RRM, which is contained in the RNA15 subunit of the complex. The RRM of RNA15 has a strong preference for GU-rich RNAs, mediated by a binding pocket that is entirely conserved in both yeast and vertebrate RNA15 orthologs.

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1720409875   1 MLYEFFVKVYPsCRGGKVVLDP-TGVSKGYGFVKFTDE 37
Cdd:cd12398    16 QLKEIFSEVGP-VVSFRLVTDReTGKPKGYGFCEFRDA 52