Atrophin-1 family; Atrophin-1 is the protein product of the dentatorubral-pallidoluysian atrophy (DRPLA) gene. DRPLA OMIM:125370 is a progressive neurodegenerative disorder. It is caused by the expansion of a CAG repeat in the DRPLA gene on chromosome 12p. This results in an extended polyglutamine region in atrophin-1, that is thought to confer toxicity to the protein, possibly through altering its interactions with other proteins. The expansion of a CAG repeat is also the underlying defect in six other neurodegenerative disorders, including Huntington's disease. One interaction of expanded polyglutamine repeats that is thought to be pathogenic is that with the short glutamine repeat in the transcriptional coactivator CREB binding protein, CBP. This interaction draws CBP away from its usual nuclear location to the expanded polyglutamine repeat protein aggregates that are characteriztic of the polyglutamine neurodegenerative disorders. This interferes with CBP-mediated transcription and causes cytotoxicity.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059   288 SQQISNSdtPSPPPGLSKSnPVIPISSSNHSARSPFEGAvtESQSLFSDNFRHPNPIPSGLPPFPSSPQTSSDWPTAPEP 367
Cdd:pfam03154 421 SQQLPPP--PAQPPVLTQS-QSLPPPAASHPPTSGLHQV--PSQSPFPQHPFVPGGPPPITPPSGPPTSTSSAMPGIQPP 495

                          90
                  ....*....|....*
gi 56550059   368 QSLFTSETIPVSSST 382
Cdd:pfam03154 496 SSASVSSSGPVPAAV 510

RNA recognition motif (RRM) found in Eukaryotic CCR4-NOT transcription complex subunit 4 (NOT4) and similar proteins; This subfamily corresponds to the RRM of NOT4, also termed CCR4-associated factor 4, or E3 ubiquitin-protein ligase CNOT4, or potential transcriptional repressor NOT4Hp, a component of the CCR4-NOT complex, a global negative regulator of RNA polymerase II transcription. NOT4 functions as an ubiquitin-protein ligase (E3). It contains an N-terminal C4C4 type RING finger motif, followed by a RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The RING fingers may interact with a subset of ubiquitin-conjugating enzymes (E2s), including UbcH5B, and mediate protein-protein interactions. T

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 104 RVVQKNLVFVVGLSQRLADPEVLKRPEYFGKFGKIHKVVINNSTSYAGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDG 183
Cdd:cd12438   1 RVVQKNLVYVVGLPPRLADEEVLKRPEYFGQYGKIKKIVINRSTSYAGSQGPSASAYVTYSRKEDALRAIQAVDGFVLDG 80

                        90
                ....*....|....*...
gi 56550059 184 RTLKASLGTTKYCSYFLK 201
Cdd:cd12438  81 RTLKASFGTTKYCSSFLR 98

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 56550059    122 DPEVLKR-----PEYFGKFGKIHKVVINNSTSYAGSQGpsaSAYVTYIRSEDALRAIQCVNNVVVDGRTLKAS 189
Cdd:smart00361   1 KDEDFERelkeeEEYFGEVGKINKIYIDDVGYENHKRG---NVYITFERSEDAARAIVDLNGRYFDGRLVKAE 70

Atrophin-1 family; Atrophin-1 is the protein product of the dentatorubral-pallidoluysian atrophy (DRPLA) gene. DRPLA OMIM:125370 is a progressive neurodegenerative disorder. It is caused by the expansion of a CAG repeat in the DRPLA gene on chromosome 12p. This results in an extended polyglutamine region in atrophin-1, that is thought to confer toxicity to the protein, possibly through altering its interactions with other proteins. The expansion of a CAG repeat is also the underlying defect in six other neurodegenerative disorders, including Huntington's disease. One interaction of expanded polyglutamine repeats that is thought to be pathogenic is that with the short glutamine repeat in the transcriptional coactivator CREB binding protein, CBP. This interaction draws CBP away from its usual nuclear location to the expanded polyglutamine repeat protein aggregates that are characteriztic of the polyglutamine neurodegenerative disorders. This interferes with CBP-mediated transcription and causes cytotoxicity.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059   288 SQQISNSdtPSPPPGLSKSnPVIPISSSNHSARSPFEGAvtESQSLFSDNFRHPNPIPSGLPPFPSSPQTSSDWPTAPEP 367
Cdd:pfam03154 421 SQQLPPP--PAQPPVLTQS-QSLPPPAASHPPTSGLHQV--PSQSPFPQHPFVPGGPPPITPPSGPPTSTSSAMPGIQPP 495

                          90
                  ....*....|....*
gi 56550059   368 QSLFTSETIPVSSST 382
Cdd:pfam03154 496 SSASVSSSGPVPAAV 510

RNA recognition motif (RRM) found in Eukaryotic CCR4-NOT transcription complex subunit 4 (NOT4) and similar proteins; This subfamily corresponds to the RRM of NOT4, also termed CCR4-associated factor 4, or E3 ubiquitin-protein ligase CNOT4, or potential transcriptional repressor NOT4Hp, a component of the CCR4-NOT complex, a global negative regulator of RNA polymerase II transcription. NOT4 functions as an ubiquitin-protein ligase (E3). It contains an N-terminal C4C4 type RING finger motif, followed by a RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The RING fingers may interact with a subset of ubiquitin-conjugating enzymes (E2s), including UbcH5B, and mediate protein-protein interactions. T

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 104 RVVQKNLVFVVGLSQRLADPEVLKRPEYFGKFGKIHKVVINNSTSYAGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDG 183
Cdd:cd12438   1 RVVQKNLVYVVGLPPRLADEEVLKRPEYFGQYGKIKKIVINRSTSYAGSQGPSASAYVTYSRKEDALRAIQAVDGFVLDG 80

                        90
                ....*....|....*...
gi 56550059 184 RTLKASLGTTKYCSYFLK 201
Cdd:cd12438  81 RTLKASFGTTKYCSSFLR 98

RING/Ubox like zinc-binding domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 56550059    14 CPLCMEPLEIDDINFFPCTCGYQICRFCWHRIRTDENGLCPACRKPY 60
Cdd:pfam14570   1 CPLCDEKLDETDKDFYPCECGYQICRFCYHDILENEGGRCPGCREPY 47

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 56550059 111 VFVVGLSQRLaDPEVLKrpEYFGKFGKIHKVVINNStsyaGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDGRTLKAS 189
Cdd:cd00590   1 LFVGNLPPDT-TEEDLR--ELFSKFGEVVSVRIVRD----RDGKSKGFAFVEFESPEDAEKALEALNGTELGGRPLKVS 72

RNA recognition motif 3 (RRM3) 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 third RRM motif.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 109 NLVFVVGLSQRLADPEVLkrpEYFGKFGKIHKVVINNSTSYAgsqgpSASAYVTYIRSEDALRAIQCVNNVVVDGRTLKA 188
Cdd:cd21603   1 NAIFVKNLPLDTNNDEIL---DFFSKVGPIKSVFTSPKYKYN-----SLWAFVTYKKGSDTEKAIKLLNGTLFKGRTIEV 72

                .
gi 56550059 189 S 189
Cdd:cd21603  73 T 73

HC subclass of RING (RING-HC) finger and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers. Some have a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle, and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 56550059  13 ECPLCMEPLeiddINFFPCTCGYQICRFCWHRIRTDENGLCPAC 56
Cdd:cd16449   2 ECPICLERL----KDPVLLPCGHVFCRECIRRLLESGSIKCPIC 41

RNA recognition motif (RRM) found in THO complex subunit 4 (THOC4) and similar proteins; This subgroup corresponds to the RRM of THOC4, also termed transcriptional coactivator Aly/REF, or ally of AML-1 and LEF-1, or bZIP-enhancing factor BEF, an mRNA transporter protein with a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It is involved in RNA transportation from the nucleus. THOC4 was initially identified as a transcription coactivator of LEF-1 and AML-1 for the TCRalpha enhancer function. In addition, THOC4 specifically binds to rhesus (RH) promoter in erythroid. It might be a novel transcription cofactor for erythroid-specific genes.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 56550059 130 EYFGKFGKIHKVVINnstsYAGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDGRTLKASL 190
Cdd:cd12680  19 ELFAEFGTLKKAAVH----YDRSGRSLGTAEVVFERRADALKAMKQYNGVPLDGRPMKIQL 75

RNA recognition motif (RRM) found in AZoospermia (DAZ) autosomal homologs, DAZL (DAZ-like) and BOULE; This subfamily corresponds to the RRM domain of two Deleted in AZoospermia (DAZ) autosomal homologs, DAZL (DAZ-like) and BOULE. BOULE is the founder member of the family and DAZL arose from BOULE in an ancestor of vertebrates. The DAZ gene subsequently originated from a duplication transposition of the DAZL gene. Invertebrates contain a single DAZ homolog, BOULE, while vertebrates, other than catarrhine primates, possess both BOULE and DAZL genes. The catarrhine primates possess BOULE, DAZL, and DAZ genes. The family members encode closely related RNA-binding proteins that are required for fertility in numerous organisms. These proteins contain an RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a varying number of copies of a DAZ motif, believed to mediate protein-protein interactions. DAZL and BOULE contain a single copy of the DAZ motif, while DAZ proteins can contain 8-24 copies of this repeat. 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        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 109 NLVFVVGLSQRLADPEvLKrpEYFGKFGKIHKVVI-----NNSTSYAgsqgpsasaYVTYIRSEDALRAIQCVNNVVVDG 183
Cdd:cd12412   3 NRIFVGGIDWDTTEEE-LR--EFFSKFGKVKDVKIikdraGVSKGYG---------FVTFETQEDAEKIQKWGANLVFKG 70

                ....
gi 56550059 184 RTLK 187
Cdd:cd12412  71 KKLN 74

RNA recognition motif (RRM) found in the scaffold attachment factor (SAFB) family; This subfamily corresponds to the RRM domain of the SAFB family, including scaffold attachment factor B1 (SAFB1), scaffold attachment factor B2 (SAFB2), SAFB-like transcriptional modulator (SLTM), and similar proteins, which are ubiquitously expressed. SAFB1, SAFB2 and SLTM have been implicated in many diverse cellular processes including cell growth and transformation, stress response, and apoptosis. They share high sequence similarities and all contain a scaffold attachment factor-box (SAF-box, also known as SAP domain) DNA-binding motif, an RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a region rich in glutamine and arginine residues. SAFB1 is a nuclear protein with a distribution similar to that of SLTM, but unlike that of SAFB2, which is also found in the cytoplasm. To a large extent, SAFB1 and SLTM might share similar functions, such as the inhibition of an oestrogen reporter gene. The additional cytoplasmic localization of SAFB2 implies that it could play additional roles in the cytoplasmic compartment which are distinct from the nuclear functions shared with SAFB1 and SLTM.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 56550059 112 FVVGLSQ--RLADpevLKrpEYFGKFGKI--HKVVINNSTSYAGSQGpsasaYVTYIRSEDALRAIQCVNNVVVDGRTL 186
Cdd:cd12417   3 WISGLSDttKAAD---LK--KIFSKYGKVvsAKVVTSARTPGSRCYG-----YVTMASVEEADLCIKSLNKTELHGRVI 71

RNA recognition motif in negative elongation factor E (NELF-E) and similar proteins; This subfamily corresponds to the RRM of NELF-E, also termed RNA-binding protein RD. NELF-E is the RNA-binding subunit of cellular negative transcription elongation factor NELF (negative elongation factor) involved in transcriptional regulation of HIV-1 by binding to the stem of the viral transactivation-response element (TAR) RNA which is synthesized by cellular RNA polymerase II at the viral long terminal repeat. NELF is a heterotetrameric protein consisting of NELF A, B, C or the splice variant D, and E. NELF-E contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It plays a role in the control of HIV transcription by binding to TAR RNA. In addition, NELF-E is associated with the NELF-B subunit, probably via a leucine zipper motif.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 107 QKNLVFVVGLSqrlADPEVLKrpEYFGKFGKIHKVVINNstsyagsqgPSASAYVTYIRSEDALRAIQCVNNVVVDGRTL 186
Cdd:cd12305   3 KGNTVYVSGYG---ITEDVLK--KAFSPFGNIINISMEI---------EKNCAFVTFEKMESADQAIAELNGTTVEGVQL 68

                ....
gi 56550059 187 KASL 190
Cdd:cd12305  69 KVSI 72

BRcat domain found in RING finger protein 216 (RNF216); RNF216, also called Triad domain-containing protein 3 (Triad3A), ubiquitin-conjugating enzyme 7-interacting protein 1, or zinc finger protein inhibiting NF-kappa-B (ZIN), is an RBR-type E3 ubiquitin-protein ligase that interacts with several components of the Toll-like receptor (TLR) signaling pathway and promotes their proteolytic degradation. It negatively regulates the RIG-I RNA sensing pathway through Lys48-linked, ubiquitin-mediated degradation of the tumor necrosis factor (TNF) receptor-associated factor 3 (TRAF3) adapter following RNA virus infection. It also controls ubiquitination and proteasomal degradation of receptor-interacting protein 1 (RIP1), a serine/threonine protein kinase that is critically involved in TNF receptor-1-induced NF-kappa B activation, following disruption of Hsp90 binding. Moreover, RNF216 is involved in inflammatory diseases by strongly inhibiting autophagy in macrophages. It interacts with and ubiquitinates BECN1, a key regulator in autophagy, thereby contributing to BECN1 degradation. It regulates synaptic strength by ubiquitination of Arc, resulting in its rapid proteasomal degradation. It is also a key negative regulator of sustained 2DL4/KIR2DL4 (killer cell Ig-like receptor with two Ig-like domains and a long cytoplasmic domain 4)-mediated NF-kappaB signaling from internalized 2DL4, which functions by promoting ubiquitylation and degradation of endocytosed receptor from early endosomes. Furthermore, RNF216 interacts with human immunodeficiency virus type 1 (HIV-1) virion infectivity factor (Vif) protein, which is essential for the productive infection of primary human CD4 T lymphocytes and macrophages. Mutations in RNF216 may result in Gordon Holmes syndrome, a condition defined by hypogonadotropic hypogonadism and cerebellar ataxia, as well as in autosomal recessive Huntington-like disorder. RNF216 contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of RNF216 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 56550059   9 EDPVECPLCMEPLEIDDINF--FPC---TCGYQICRFC---WHRIRT 47
Cdd:cd20339   2 EGLERCPFCNYAAILDPTEVkvFRCpnpECRKESCRKCkkeWHIPLT 48

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        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 111 VFVVGLSQrLADPEVLKrpEYFGKFGKIH--KVVINNSTSYagsqgPSASAYVTYIRSEDALRAIQCVNN------VVVD 182
Cdd:cd12415   3 VFIRNLSF-DTTEEDLK--EFFSKFGEVKyaRIVLDKDTGH-----SKGTAFVQFKTKESADKCIEAANDesedggLVLD 74

                ....*...
gi 56550059 183 GRTLKASL 190
Cdd:cd12415  75 GRKLIVSL 82

RNA recognition motif (RRM) found in eukaryotic RNA-binding protein 18 and similar proteins; This subfamily corresponds to the RRM of RBM18, a putative RNA-binding protein containing a well-conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The biological role of RBM18 remains unclear.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 56550059 111 VFVVGLSQRLADPEVLKrpeYFGKFGKI--HKVVINNSTSYAGSqgPSASAYVTYIRSEDALRAIQCVNNVVVDGRTL 186
Cdd:cd12355   2 LWIGNLDPRLTEYHLLK---LLSKYGKIkkFDFLFHKTGPLKGQ--PRGYCFVTFETKEEAEKAIECLNGKLALGKKL 74

RNA recognition motif 3 (RRM3) found in the Hu proteins family; This subfamily corresponds to the RRM3 of the Hu proteins family which represent 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. 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        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 111 VFVVGLSQRlADPEVLKRpeYFGKFGKIHKV-VINNSTSyagsQGPSASAYVTYIRSEDALRAIQCVNNVVVDGRTLKAS 189
Cdd:cd12377   2 IFVYNLAPD-ADESLLWQ--LFGPFGAVQNVkIIRDFTT----NKCKGYGFVTMTNYDEAAVAIASLNGYRLGGRVLQVS 74

                .
gi 56550059 190 L 190
Cdd:cd12377  75 F 75

RNA recognition motif 1 (RRM1) found in Schizosaccharomyces pombe mRNA export factor Crp79 and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Members in this family contain three 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        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 56550059 109 NLVFVVGLSQRLADPEVLKrpeYFGKFGKIHKVVINNSTSYAGSQGpSASAYVTYIRSEDALRAIQCVNNVVVDGRTL 186
Cdd:cd21619   2 NTIYVGNIDMTINEDALEK---IFSRYGQVESVRRPPIHTDKADRT-TGFGFIKYTDAESAERAMQQADGILLGRRRL 75

RING finger, HC subclass, found in tripartite motif-containing protein 32 (TRIM32) and similar proteins; TRIM32, also known as 72 kDa Tat-interacting protein, zinc finger protein HT2A, or BBS11, is an E3 ubiquitin-protein ligase that promotes degradation of several targets, including actin, PIASgamma, Abl interactor 2, dysbindin, X-linked inhibitor of apoptosis (XIAP), p73 transcription factor, thin filaments and Z-bands during fasting. It plays important roles in neuronal differentiation of neural progenitor cells, as well as in controlling cell fate in skeletal muscle progenitor cells. It reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation. It also functions as a pluripotency-reprogramming roadblock that facilitates cellular transition towards differentiation by modulating the levels of Oct4 and cMyc. Moreover, TRIM32 is an intrinsic influenza A virus (IAV) restriction factor which senses and targets the polymerase basic protein 1 (PB1) for ubiquitination and protein degradation. It also plays a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo, binds specifically to the activation domain of HIV-1 Tat, and can also interact with the HIV-2 and EIAV Tat proteins in vivo. Furthermore, TRIM32 regulates myoblast proliferation by controlling turnover of NDRG2 (N-myc downstream-regulated gene). It negatively regulates tumor suppressor p53 to promote tumorigenesis. It also facilitates degradation of MYCN on spindle poles and induces asymmetric cell division in human neuroblastoma cells. In addition, TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. It also plays a role in regeneration by affecting satellite cell cycle progression via modulation of the SUMO ligase PIASy (PIAS4). Defects in TRIM32 leads to limb-girdle muscular dystrophy type 2H (LGMD2H), sarcotubular myopathies (STM) and Bardet-Biedl syndrome. TRIM32 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain. The NHL domain mediates the interaction with Argonaute proteins and consequently allows TRIM32 to modulate the activity of certain miRNAs.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 56550059  12 VECPLCMEPLeiDDINFFP--CTCGYQICRFCWHRIRTDENGL---CPACRK 58
Cdd:cd16587   1 LECPICLESF--DEGQLRPklLHCGHTICEQCLEKLLASLSINgvrCPFCRK 50

RNA recognition motif 1 (RRM1) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM1 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        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 111 VFVVGLSQRLADPEVLkrpEYFGKFGKIHK--VVINNstsyaGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDGRTLKA 188
Cdd:cd12413   2 LFVRNLPYDTTDEQLE---ELFSDVGPVKRcfVVKDK-----GKDKCRGFGYVTFALAEDAQRALEEVKGKKFGGRKIKV 73

                ..
gi 56550059 189 SL 190
Cdd:cd12413  74 EL 75

RING finger, HC subclass, found in tripartite motif-containing proteins, TRIM7, TRIM11 and TRIM27, and similar proteins; TRIM7, TRIM11 and TRIM27, closely related tripartite motif-containing proteins, belong to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) by mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. TRIM11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM27, also known as RING finger protein 76 (RNF76), RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. In addition, it inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. TRIM27 promotes a non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. TRIM27 also forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is a component of an estrogen receptor 1 (ESR1) regulatory complex that is involved in estrogen receptor-mediated transcription in MCF-7 cells.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 56550059  14 CPLCME----PLEIDdinffpctCGYQICRFC----WHRirTDENGLCPACRKPYPEDP 64
Cdd:cd16594   8 CPICLDyftdPVTLD--------CGHSFCRACiarcWEE--PETSASCPQCRETCPQRN 56

RNA recognition motif (RRM) found in the Aly/REF family; This subfamily corresponds to the RRM of Aly/REF family which includes THO complex subunit 4 (THOC4, also termed Aly/REF), S6K1 Aly/REF-like target (SKAR, also termed PDIP3 or PDIP46) and similar proteins. THOC4 is an mRNA transporter protein with a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It is involved in RNA transportation from the nucleus, and was initially identified as a transcription coactivator of LEF-1 and AML-1 for the TCRalpha enhancer function. In addition, THOC4 specifically binds to rhesus (RH) promoter in erythroid, and might be a novel transcription cofactor for erythroid-specific genes. SKAR shows high sequence homology with THOC4 and possesses one RRM as well. SKAR is widely expressed and localizes to the nucleus. It may be a critical player in the function of S6K1 in cell and organism growth control by binding the activated, hyperphosphorylated form of S6K1 but not S6K2. Furthermore, SKAR functions as a protein partner of the p50 subunit of DNA polymerase delta. In addition, SKAR may have particular importance in pancreatic beta cell size determination and insulin secretion.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 56550059 130 EYFGKFGKIHKVVINnstsYAGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDGRTLK 187
Cdd:cd12418  19 ELFGRVGPVKSVKIN----YDRSGRSTGTAYVVFERPEDAEKAIKQFDGVLLDGQPMK 72

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 56550059   9 EDPVECPLCMEPLeiDDinffPCT--CGYQICRFC----WHRIRTDENgLCPACRKPYPEDPAVYK 68
Cdd:cd16597   3 EEELTCSICLELF--KD----PVTlpCGHNFCGVCiektWDSQHGSEY-SCPQCRATFPRRPELHK 61

Modified RING finger, HC subclass (C4C4-type), found in Arabidopsis thaliana cellulose synthase A (CesA) catalytic subunits 1-10, and similar proteins from plants; This subfamily includes plant catalytic subunits of cellulose synthase terminal complexes ("rosettes") required for beta-1,4-glucan microfibril crystallization, a major mechanism of cell wall formation. CesA1, also known as protein RADIALLY SWOLLEN 1 (RSW1), is required during embryogenesis for cell elongation, orientation of cell expansion and complex cell wall formations, such as interdigitated pattern of epidermal pavement cells, stomatal guard cells, and trichomes. It plays a role in lateral roots formation, but seems unnecessary for the development of tip-growing cells such as root hairs. CesA2, also known as Ath-A, is involved in the primary cell wall formation. It forms a homodimer. CesA3, also known as constitutive expression of VSP1 protein 1, isoxaben-resistant protein 1, Ath-B, protein ECTOPIC LIGNIN 1, or protein RADIALLY SWOLLEN 5 (RSW5), is involved in primary cell wall formation, especially in roots. CesA4, also known as protein IRREGULAR XYLEM 5 (IRX5), is involved in the secondary cell wall formation, and required for xylem cell wall thickening. CesA5 may be partially redundant with CesA6. CesA6, also known as AraxCelA, isoxaben-resistant protein 2, protein PROCUSTE 1, or protein QUILL, is involved in primary cell wall formation. Like CesA1, CesA6 is critical for cell expansion. CESA6-dependent cell elongation seems to be independent of gibberellic acid, auxin, and ethylene. CesA6 interacts with and moves along cortical microtubules for the process of cellulose deposition. CesA7, also known as protein FRAGILE FIBER 5, or protein IRREGULAR XYLEM 3 (IRX3), and CesA8, also known as protein IRREGULAR XYLEM 1 (IRX1) or protein LEAF WILTING 2, are both involved in secondary cell wall formation and also required for xylem cell wall thickening. The biological function of CesA9 and CesA10 remain unclear. CesA1, CesA3, and CesA6 form a functional complex essential for primary cell wall cellulose synthesis, while CesA4, CesA7, and CesA8 form a functional complex located in secondary cell wall deposition sites. All family members contain an N-terminal C4C4-type RING-HC finger and a C-terminal glycosyltransferase family A (GT-A) domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 56550059  14 CPLCMEPLEIDDIN--FFPCT-CGYQICRFCWHRIRTDENGLCPACRKP 59
Cdd:cd16617   3 CQICGDEIGLTVNGelFVACNeCGFPVCRPCYEYERKEGNQCCPQCKTR 51

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 56550059  12 VECPLCMEPLEIdDINFFPCTcgYQICRFCWHRIRTDENGL-CPACRKP 59
Cdd:cd16749   1 LECPVCFEKLDV-TAKVLPCQ--HTFCKPCLQRIFKARKELrCPECRTP 46

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|...
gi 56550059     14 CPLCMEPLEIDdinFFPCTCGYQICRFCWHRIRTDENGLCPAC 56
Cdd:smart00184   1 CPICLEEYLKD---PVILPCGHTFCRSCIRKWLESGNNTCPIC 40

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 56550059    13 ECPLCMEPLEIDDiNFFPCTCGYQICRFC---WHRIrtdeNGLCPACR 57
Cdd:pfam13639   2 ECPICLEEFEEGD-KVVVLPCGHHFHRECldkWLRS----SNTCPLCR 44

RING finger, HC subclass, found in two RING fingers and DRIL [double RING finger linked] 1 (TRIAD1); TRIAD1, also known as ariadne-2 (ARI-2), protein ariadne-2 homolog, Ariadne RBR E3 ubiquitin protein ligase 2 (ARIH2), or UbcM4-interacting protein 48, is an RBR-type E3 ubiquitin-protein ligase that catalyzes the formation of polyubiquitin chains linked via lysine-48, as well as lysine-63 residues. Its auto-ubiquitylation can be catalyzed by the E2 conjugating enzyme UBCH7. TRIAD1 has been implicated in hematopoiesis, specifically in myelopoiesis, as well as in embryogenesis. It functions as a regulator of endosomal transport and is required for the proper function of multivesicular bodies. It also acts as a novel ubiquitination target for proteasome-dependent degradation by murine double minute 2 (MDM2). As a proapoptotic protein, TRIAD1 promotes p53 activation, and inhibits MDM2-mediated p53 ubiquitination and degradation. Furthermore, TRIAD1 can inhibit the ubiquitination and proteasomal degradation of growth factor independence 1 (Gfi1), a transcriptional repressor essential for the function and development of many different hematopoietic lineages. TRIAD1 contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                        10        20        30
                ....*....|....*....|....*....|..
gi 56550059  12 VECPLCMEPLEIDdiNFFPCTCGYQICRFCWH 43
Cdd:cd16773   1 VTCGVCCEDVPKD--ELFSLACGHYFCNDCWK 30

RNA recognition motif 2 (RRM2) found in yeast nucleolar protein 4 (Nop4p) and similar proteins; This subgroup corresponds to the RRM2 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 56550059 122 DPEVLKrpEYFGKFGKIHKVVINNStsyaGSQGPSASAYVTYIRSEDALRAIQCVNNVVVDGRTL 186
Cdd:cd12675  14 KPVHLK--KLFGRYGKVVEATIPRK----KGGKLSGFAFVTMKGRKNAEEALESVNGLEIDGRPV 72

RING finger, HC subclass, found in RING finger protein 138 (RNF138) and similar proteins; RNF138, also known as Nemo-like kinase-associated RING finger protein (NARF) or NLK-associated RING finger protein, is an E3 ubiquitin-protein ligase that plays an important role in glioma cell proliferation, apoptosis, and cell cycle. It specifically cooperates with the E2 conjugating enzyme E2-25K (Hip-2/UbcH1), regulates the ubiquitylation and degradation of T cell factor/lymphoid enhancer factor (TCF/LEF), and further suppresses Wnt-beta-catenin signaling. RNF138, together with three closely related proteins: RNF114, RNF125 and RNF166, forms a novel family of ubiquitin ligases with a C3HC4-type RING-HC finger, a C2HC-, and two C2H2-type zinc fingers, as well as a ubiquitin interacting motif (UIM).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 56550059  13 ECPLCMEPLEiDDINFFPCtcGYQICRFCWHRIRTDENGLCPACRKPY 60
Cdd:cd16544   4 TCPVCQEVLK-DPVELPPC--RHIFCKACILLALRSSGARCPLCRGPV 48

RNA recognition motif (RRM) found in UHM domain of 45 kDa-splicing factor (SPF45) and similar proteins; This subfamily corresponds to the RRM found in UHM domain of 45 kDa-splicing factor (SPF45 or RBM17), poly(U)-binding-splicing factor PUF60 (FIR or Hfp or RoBP1 or Siah-BP1), and similar proteins. SPF45 is an RNA-binding protein consisting of an unstructured N-terminal region, followed by a G-patch motif and a C-terminal U2AF (U2 auxiliary factor) homology motifs (UHM) that harbors a RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain) and an Arg-Xaa-Phe sequence motif. SPF45 regulates alternative splicing of the apoptosis regulatory gene FAS (also known as CD95). It induces exon 6 skipping in FAS pre-mRNA through the UHM domain that binds to tryptophan-containing linear peptide motifs (UHM ligand motifs, ULMs) present in the 3' splice site-recognizing factors U2AF65, SF1 and SF3b155. PUF60 is an essential splicing factor that functions as a poly-U RNA-binding protein required to reconstitute splicing in depleted nuclear extracts. Its function is enhanced through interaction with U2 auxiliary factor U2AF65. PUF60 also controls human c-myc gene expression by binding and inhibiting the transcription factor far upstream sequence element (FUSE)-binding-protein (FBP), an activator of c-myc promoters. PUF60 contains two central RRMs and a C-terminal UHM domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 56550059 130 EYFGKFGKIHKVVINNSTSYAGSQgpSASAYVTYIRSEDALRAIQCVNNVVVDGRTLKA 188
Cdd:cd12374  25 EECSKYGKVLNVIIHEVASSEADD--AVRVFVEFEDADEAIKAFRALNGRFFGGRKVKA 81

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 56550059 111 VFVVGLSQRLaDPEVLKrpEYFGKFGKIHKVVINNSTSYAGSQGPSASAYVTYIRSEDALRAIQcVNNVVVDGRTLKASL 190
Cdd:cd12298   3 IRVRNLDFEL-DEEALR--GIFEKFGEIESINIPKKQKNRKGRHNNGFAFVTFEDADSAESALQ-LNGTLLDNRKISVSL 78

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 56550059  14 CPLCMepleidDINFFP---CTCGYQICRFCWHRIRTDE--NGLCPACRKPypedpaVYKPLSQEEL 75
Cdd:cd16554   5 CPVCL------DLYYDPymcYPCGHIFCEPCLRQLAKSSpkNTPCPLCRTT------IRRVFFQEEL 59

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 56550059    10 DPVECPLCMEplEIDDINFFPCTCGYqICRFCWHRIRTdENGLCPACRKP 59
Cdd:pfam13920   1 EDLLCVICLD--RPRNVVLLPCGHLC-LCEECAERLLR-KKKKCPICRQP 46