RNA recognition motif;

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gi 569003374    926 VVYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQ--KHGFITFRCSEHA--ALSVRNGATLRKR 990
Cdd:smart00360    1 TLFVGNLPPDTTEEELRELFSKFGKVESVRLVRDKETGKskGFAFVEFESEEDAekALEALNGKELDGR 69

splicing factor, CC1-like family; This model represents a subfamily of RNA splicing factors including the Pad-1 protein (N. crassa), CAPER (M. musculus) and CC1.3 (H.sapiens). These proteins are characterized by an N-terminal arginine-rich, low complexity domain followed by three (or in the case of 4 H. sapiens paralogs, two) RNA recognition domains (rrm: pfam00706). These splicing factors are closely related to the U2AF splicing factor family (TIGR01642). A homologous gene from Plasmodium falciparum was identified in the course of the analysis of that genome at TIGR and was included in the seed.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 569003374   927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQK--HGFITFRCSEHA--ALSVRNGATLRKR 990
Cdd:TIGR01622  217 LYVGNLHFNITEQDLRQIFEPFGEIEFVQLQKDPETGRSkgYGFIQFRDAEQAkeALEKMNGFELAGR 284

glycine-rich RNA-binding protein 4; Provisional

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569003374  892 RKNFRRESRGPCSDGTPSVRHARKRrekaigegrvVYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQKH--GFI 969
Cdd:PLN03134   12 RQNISSNGNVPVTSMLGSLRLMSTK----------LFIGGLSWGTDDASLRDAFAHFGDVVDAKVIVDRETGRSRgfGFV 81

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|..
gi 569003374  970 TFRC--SEHAALSVRNGATLRKRN--------EPSFHLSYGG 1001
Cdd:PLN03134   82 NFNDegAATAAISEMDGKELNGRHirvnpandRPSAPRAYGG 123

RNA recognition motif (RRM) found in the peroxisome proliferator-activated receptor gamma coactivator 1A (PGC-1alpha) family of regulated coactivators; This subfamily corresponds to the RRM of PGC-1alpha, PGC-1beta, and PGC-1-related coactivator (PRC), which serve as mediators between environmental or endogenous signals and the transcriptional machinery governing mitochondrial biogenesis. They play an important integrative role in the control of respiratory gene expression through interacting with a number of transcription factors, such as NRF-1, NRF-2, ERR, CREB and YY1. All family members are multi-domain proteins containing the N-terminal activation domain, an LXXLL coactivator signature, a tetrapeptide motif (DHDY) responsible for HCF binding, and an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). In contrast to PGC-1alpha and PRC, PGC-1beta possesses two glutamic/aspartic acid-rich acidic domains, but lacks most of the arginine/serine (SR)-rich domain that is responsible for the regulation of RNA processing.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569003374  923 EGRVVYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRsKRGQKHGFITFRCSEHAALSVRNGATLRKRNEPSFHLSYGGL 1002
Cdd:cd12357     1 ERRVVYVGKLEQDTTRSELRRRFEVFGEIEECTVHFR-ERGDKYGFVTYRYSEDAFLALENGHDLRKRNEPMFDLSFGGR 79

                          90
                  ....*....|..
gi 569003374 1003 RHFRWPRYTDYD 1014
Cdd:cd12357    80 RAFCKSSYADLD 91

RNA recognition motif (RRM) found in peroxisome proliferator-activated receptor gamma coactivator-related protein 1 (PRC) and similar proteins; This subgroup corresponds to the RRM of PRC, also termed PGC-1-related coactivator, one of the members of PGC-1 transcriptional coactivators family, including peroxisome proliferator-activated receptor gamma coactivators PGC-1alpha and PGC-1beta. Unlike PGC-1alpha and PGC-1beta, PRC is ubiquitous and more abundantly expressed in proliferating cells than in growth-arrested cells. PRC has been implicated in the regulation of several metabolic pathways, mitochondrial biogenesis, and cell growth. It functions as a growth-regulated transcriptional cofactor activating many nuclear genes specifying mitochondrial respiratory function. PRC directly interacts with nuclear transcriptional factors implicated in respiratory chain expression including nuclear respiratory factors 1 and 2 (NRF-1 and NRF-2), CREB (cAMP-response element-binding protein), and estrogen-related receptor alpha (ERRalpha). It interacts indirectly with the NRF-2beta subunit through host cell factor (HCF), a cellular protein involved in herpes simplex virus (HSV) infection and cell cycle regulation. Furthermore, like PGC-1alpha and PGC-1beta, PRC can transactivate a number of NRF-dependent nuclear genes required for mitochondrial respiratory function, including those encoding cytochrome c, 5-aminolevulinate synthase, Tfam, and TFB1M, and TFB2M. Further research indicates that PRC may also act as a sensor of metabolic stress that orchestrates a redox-sensitive program of inflammatory gene expression. PRC is a multi-domain protein containing an N-terminal activation domain, an LXXLL coactivator signature, a central proline-rich region, a tetrapeptide motif (DHDY) responsible for HCF binding, a C-terminal arginine/serine-rich (SR) domain, and an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569003374  923 EGRVVYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKrGQKHGFITFRCSEHAALSVRNGATLRKRNEPSFHLSYGGL 1002
Cdd:cd12624     1 ERRVVYIGKIRGRMTRSELKDRFSVFGEIEECTIHFREE-GDNYGFVTYRYTEDAFAAIENGHKLRRPDELPFDLCFGGR 79

                          90
                  ....*....|..
gi 569003374 1003 RHFRWPRYTDYD 1014
Cdd:cd12624    80 RQFCKSSYADLD 91

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQK-HGFITFRCSEHA--ALSVRNGATLRKR 990
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDRDGKSKgFAFVEFESPEDAekALEALNGTELGGR 67

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLT-----RSkRGqkHGFITFRCSEHA--ALSVRNGATLRKRN 991
Cdd:cd21608     2 LYVGNLSWDTTEDDLRDLFSEFGEVESAKVITdretgRS-RG--FGFVTFSTAEAAeaAIDALNGKELDGRS 70

RNA recognition motif 3 (RRM3) found found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM3 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 an 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. 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. Moreover, 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.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLT----RSKRgqkHGFITFRCSEHAALSV 981
Cdd:cd12380     4 VYVKNFGEDVDDDELKELFEKYGKITSAKVMKddsgKSKG---FGFVNFENHEAAQKAV 59

RNA recognition motif 2 (RRM2) found in yeast meiotic activator RIM4 and similar proteins; This subfamily corresponds to the RRM2 of RIM4, also termed regulator of IME2 protein 4, a putative RNA binding protein that is expressed at elevated levels early in meiosis. It functions as a meiotic activator required for both the IME1- and IME2-dependent pathways of meiotic gene expression, as well as early events of meiosis, such as meiotic division and recombination, in Saccharomyces cerevisiae. RIM4 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The family also includes a putative RNA-binding protein termed multicopy suppressor of sporulation protein Msa1. It is a putative RNA-binding protein encoded by a novel gene, msa1, from the fission yeast Schizosaccharomyces pombe. Msa1 may be involved in the inhibition of sexual differentiation by controlling the expression of Ste11-regulated genes, possibly through the pheromone-signaling pathway. Like RIM4, Msa1 also contains two RRMs, both of which are essential for the function of Msa1.

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gi 569003374  925 RVVYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQKHGFITFRCSEHAALSVR--NGATLRKR 990
Cdd:cd12454     4 LSIFVGQLDPKTTDSELFRRFSKYGKIVDCKLIKRPEPVNAFAFLRFESEEAAEAAVEeeNHSEFLNK 71

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.

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gi 569003374  928 YIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQKH--GFITFRCSEHAALSVRN 983
Cdd:cd12417     3 WISGLSDTTKAADLKKIFSKYGKVVSAKVVTSARTPGSRcyGYVTMASVEEADLCIKS 60

splicing factor, CC1-like family; This model represents a subfamily of RNA splicing factors including the Pad-1 protein (N. crassa), CAPER (M. musculus) and CC1.3 (H.sapiens). These proteins are characterized by an N-terminal arginine-rich, low complexity domain followed by three (or in the case of 4 H. sapiens paralogs, two) RNA recognition domains (rrm: pfam00706). These splicing factors are closely related to the U2AF splicing factor family (TIGR01642). A homologous gene from Plasmodium falciparum was identified in the course of the analysis of that genome at TIGR and was included in the seed.

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                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 569003374   927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQK--HGFITFRCSEHA--ALSVRNGATLRKR 990
Cdd:TIGR01622  217 LYVGNLHFNITEQDLRQIFEPFGEIEFVQLQKDPETGRSkgYGFIQFRDAEQAkeALEKMNGFELAGR 284

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.

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gi 569003374  929 IRNLSSDMSSRELKKRFEVFGEIVECQVLtRSKRGQKHG--FITFRCSEHAALSVR--NGATLRKR 990
Cdd:cd12414     4 VRNLPFKCTEDDLKKLFSKFGKVLEVTIP-KKPDGKLRGfaFVQFTNVADAAKAIKgmNGKKIKGR 68

RNA recognition motif 1 (RRM1) found in yeast multiple RNA-binding domain-containing protein 1 (MRD1) and similar proteins; This subgroup corresponds to the RRM1 of MRD1 which 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). MRD1 is essential for the initial processing at the A0-A2 cleavage sites in the 35 S pre-rRNA. It contains 5 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which may play an important structural role in organizing specific rRNA processing events.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVL-TRSKRGQKHGFITFRCSEHAALSVR 982
Cdd:cd12565     3 IIVKNLPKYVTEKRLKEHFSKKGEITDVKVMrTKDGKSRRFGFIGFKSEEEAQKAVK 59

RNA recognition motif 1 (RRM1) found in heterogeneous nuclear ribonucleoprotein A subfamily; This subfamily corresponds to the RRM1 in hnRNP A0, hnRNP A1, hnRNP A2/B1, hnRNP A3 and similar proteins. hnRNP A0 is 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 A1 is an abundant eukaryotic nuclear RNA-binding protein that may modulate splice site selection in pre-mRNA splicing. hnRNP A2/B1 is an RNA trafficking response element-binding protein that interacts with the hnRNP A2 response element (A2RE). Many mRNAs, such as myelin basic protein (MBP), myelin-associated oligodendrocytic basic protein (MOBP), carboxyanhydrase II (CAII), microtubule-associated protein tau, and amyloid precursor protein (APP) are trafficked by hnRNP A2/B1. hnRNP A3 is also a RNA trafficking response element-binding protein that participates in the trafficking of A2RE-containing RNA. The hnRNP A subfamily is characterized by 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.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLT--RSKRGQKHGFITFRCSEH--AALSVR 982
Cdd:cd12578     2 LFIGGLSYETTDDSLRNHFEQWGEITDVVVMKdpATKRSRGFGFVTYSSASEvdAAMNAR 61

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).

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gi 569003374  925 RVVYIRNLSSDMSSRELKKRFEVFGEIVECQVLtRSKRGQK---HGFITFRCSEHAALSVRNGATLR 988
Cdd:cd21615    19 KTLFVGRLDYSLTELELQKKFSKFGEIEKIRIV-RDKETGKsrgYAFIVFKSESDAKNAFKEGNGLR 84

RNA recognition motif 4 (RRM4) found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM4 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 theThe CD corresponds to the RRM. 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 an 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. Moreover, 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.

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gi 569003374  928 YIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQK-HGFITFRCSEHAALSV 981
Cdd:cd12381     5 YVKNLDDTIDDEKLREEFSPFGTITSAKVMTDEGGRSKgFGFVCFSSPEEATKAV 59

RNA recognition motif 2 (RRM2) found in RNA-binding protein Musashi homologs Musashi-1, Musashi-2 and similar proteins; This subfamily corresponds to the RRM2.in Musashi-1 (also termed Msi1), a neural RNA-binding protein putatively expressed in central nervous system (CNS) stem cells and neural progenitor cells, and associated with asymmetric divisions in neural progenitor cells. It is evolutionarily conserved from invertebrates to vertebrates. Musashi-1 is a homolog of Drosophila Musashi and Xenopus laevis nervous system-specific RNP protein-1 (Nrp-1). It has been implicated in the maintenance of the stem-cell state, differentiation, and tumorigenesis. It translationally regulates the expression of a mammalian numb gene by binding to the 3'-untranslated region of mRNA of Numb, encoding a membrane-associated inhibitor of Notch signaling, and further influences neural development. Moreover, Musashi-1 represses translation by interacting with the poly(A)-binding protein and competes for binding of the eukaryotic initiation factor-4G (eIF-4G). Musashi-2 (also termed Msi2) has been identified as a regulator of the hematopoietic stem cell (HSC) compartment and of leukemic stem cells after transplantation of cells with loss and gain of function of the gene. It influences proliferation and differentiation of HSCs and myeloid progenitors, and further modulates normal hematopoiesis and promotes aggressive myeloid leukemia. Both, Musashi-1 and Musashi-2, contain two conserved N-terminal tandem RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), along with other domains of unknown function.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQvLTRSKRGQKH---GFITFRcSEHAALSV 981
Cdd:cd12323     2 IFVGGLSANTTEDDVKKYFSQFGKVEDAM-LMFDKQTNRHrgfGFVTFE-SEDVVDKV 57

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.

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gi 569003374  928 YIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQKHG--FITF--RCSEHAALSVRNGATLRKRNEP 993
Cdd:cd12652     4 YVSGLPKTMTQKELEQLFSQFGRIITSRILCDNVTGLSRGvgFIRFdkRVEAERAIKALNGTIPPGATEP 73

RNA recognition motif 1 (RRM1) found in yeast nuclear polyadenylated RNA-binding protein 4 (Hrp1p or Nab4p) and similar proteins; This subfamily corresponds to the RRM1 of Hrp1p and similar proteins. Hrp1p or Nab4p, also termed cleavage factor IB (CFIB), is a sequence-specific trans-acting factor that is essential for mRNA 3'-end formation in yeast Saccharomyces cerevisiae. It can be UV cross-linked to RNA and specifically recognizes the (UA)6 RNA element required for both, the cleavage and poly(A) addition, steps. Moreover, Hrp1p can shuttle between the nucleus and the cytoplasm, and play an additional role in the export of mRNAs to the cytoplasm. Hrp1p also interacts with Rna15p and Rna14p, two components of CF1A. In addition, Hrp1p functions as a factor directly involved in modulating the activity of the nonsense-mediated mRNA decay (NMD) pathway. It binds specifically to a downstream sequence element (DSE)-containing RNA and interacts with Upf1p, a component of the surveillance complex, further triggering the NMD pathway. Hrp1p contains two central RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an arginine-glycine-rich region harboring repeats of the sequence RGGF/Y.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQKHG--FITFR 972
Cdd:cd12577     1 MFIGGLNWDTTEEGLRDYFSQFGTVVDCTIMKDSATGRSRGfgFLTFE 48

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.

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gi 569003374  932 LSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQK--HGFITFRCSEHA--ALSVRNGATLR-KRNEPSF 995
Cdd:cd12375     7 LPQSMTQEELRSLFGAIGPIESCKLVRDKITGQSlgYGFVNYRDPNDArkAINTLNGLDLEnKRLKVSY 75

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.

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gi 569003374   927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLtRSKRGQKHGF--ITFRCSEHAALSVRN 983
Cdd:TIGR01628  181 LYVKNLDPSVNEDKLRELFAKFGEITSAAVM-KDGSGRSRGFafVNFEKHEDAAKAVEE 238

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in RRM-containing coactivator activator/modulator (CoAA) and similar proteins; This subfamily corresponds to the RRM in CoAA (also known as RBM14 or PSP2) and RNA-binding protein 4 (RBM4). CoAA is a heterogeneous nuclear ribonucleoprotein (hnRNP)-like protein identified as a nuclear receptor coactivator. It mediates transcriptional coactivation and RNA splicing effects in a promoter-preferential manner, and is enhanced by thyroid hormone receptor-binding protein (TRBP). CoAA contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a TRBP-interacting domain. RBM4 is a ubiquitously expressed splicing factor with two isoforms, RBM4A (also known as Lark homolog) and RBM4B (also known as RBM30), which are very similar in structure and sequence. RBM4 may also function as a translational regulator of stress-associated mRNAs as well as play a role in micro-RNA-mediated gene regulation. RBM4 contains two N-terminal RRMs, a CCHC-type zinc finger, and three alanine-rich regions within their C-terminal regions. This family also includes Drosophila RNA-binding protein lark (Dlark), a homolog of human RBM4. It plays an important role in embryonic development and in the circadian regulation of adult eclosion. Dlark shares high sequence similarity with RBM4 at the N-terminal region. However, Dlark has three proline-rich segments instead of three alanine-rich segments within the C-terminal region.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLtrskrgQKHGFITFRCSEHA--ALSVRNGATLR 988
Cdd:cd12343     2 IFVGNLPDAATSEELRALFEKYGKVTECDIV------KNYAFVHMEKEEDAedAIKALNGYEFM 59

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 569003374  925 RVVYIRNLSSDMSSRELKKRFEVFGEIVECQV--LTRSKRGQKHG---FITFRcSEHAALSV--RNGATLRKRN 991
Cdd:cd12298     1 REIRVRNLDFELDEEALRGIFEKFGEIESINIpkKQKNRKGRHNNgfaFVTFE-DADSAESAlqLNGTLLDNRK 73

RNA recognition motif 2 (RRM2) found in vertebrate RNA-binding protein 4 (RBM4); This subgroup corresponds to the RRM2 of RBM4, a ubiquitously expressed splicing factor that has two isoforms, RBM4A (also known as Lark homolog) and RBM4B (also known as RBM30), which are very similar in structure and sequence. RBM4 may function as a translational regulator of stress-associated mRNAs and also plays a role in micro-RNA-mediated gene regulation. RBM4 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), a CCHC-type zinc finger, and three alanine-rich regions within their C-terminal regions. The C-terminal region may be crucial for nuclear localization and protein-protein interaction. The RRMs, in combination with the C-terminal region, are responsible for the splicing function of RBM4.

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVLtrskrgQKHGFITFRCSEHAALSVRN 983
Cdd:cd12607     3 LHVGNISSSCTNQELRAKFEEYGPVIECDIV------KDYAFVHMERAEDAMEAIRG 53

RNA recognition motif 4 (RRM4) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM4 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.

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gi 569003374  929 IRNLSSDMSSRELKK---------RFEVFGEIVECQVLTRSKRGQKH--------GFITFRCSEHA--ALSVRN 983
Cdd:cd12416     5 VRNLPKSVDDKKLKKlflkavkerAKKKGVKIKEVKVMRDKKRLNSDgkgrskgyGFVEFTEHEHAlkALRALN 78

RNA recognition motif (RRM) found in eukaryotic RNA-binding protein RBM24, RBM38 and similar proteins; This subfamily corresponds to the RRM of RBM24 and RBM38 from vertebrate, SUPpressor family member SUP-12 from Caenorhabditis elegans and similar proteins. Both, RBM24 and RBM38, are preferentially expressed in cardiac and skeletal muscle tissues. They regulate myogenic differentiation by controlling the cell cycle in a p21-dependent or -independent manner. RBM24, also termed RNA-binding region-containing protein 6, interacts with the 3'-untranslated region (UTR) of myogenin mRNA and regulates its stability in C2C12 cells. RBM38, also termed CLL-associated antigen KW-5, or HSRNASEB, or RNA-binding region-containing protein 1(RNPC1), or ssDNA-binding protein SEB4, is a direct target of the p53 family. It is required for maintaining the stability of the basal and stress-induced p21 mRNA by binding to their 3'-UTRs. It also binds the AU-/U-rich elements in p63 3'-UTR and regulates p63 mRNA stability and activity. SUP-12 is a novel tissue-specific splicing factor that controls muscle-specific splicing of the ADF/cofilin pre-mRNA in C. elegans. All family members contain a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

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gi 569003374  941 LKKRFEVFGEIVECQVLT--RSKRGQKHGFITFRCSEHAALSVRN 983
Cdd:cd12384    17 LREYFEQFGEIEEAVVITdrQTGKSRGYGFVTMADREAAERACKD 61

glycine-rich RNA-binding protein 4; Provisional

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gi 569003374  892 RKNFRRESRGPCSDGTPSVRHARKRrekaigegrvVYIRNLSSDMSSRELKKRFEVFGEIVECQVLTRSKRGQKH--GFI 969
Cdd:PLN03134   12 RQNISSNGNVPVTSMLGSLRLMSTK----------LFIGGLSWGTDDASLRDAFAHFGDVVDAKVIVDRETGRSRgfGFV 81

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gi 569003374  970 TFRC--SEHAALSVRNGATLRKRN--------EPSFHLSYGG 1001
Cdd:PLN03134   82 NFNDegAATAAISEMDGKELNGRHirvnpandRPSAPRAYGG 123

RNA recognition motif 1 (RRM1) found in heterogeneous nuclear ribonucleoprotein hnRNP A and hnRNP D subfamilies and similar proteins; This subfamily corresponds to the RRM1 in the hnRNP A subfamily which includes hnRNP A0, hnRNP A1, hnRNP A2/B1, hnRNP A3 and similar proteins. hnRNP A0 is a low abundance hnRNP protein that has been implicated in mRNA stability in mammalian cells. hnRNP A1 is an abundant eukaryotic nuclear RNA-binding protein that may modulate splice site selection in pre-mRNA splicing. hnRNP A2/B1 is an RNA trafficking response element-binding protein that interacts with the hnRNP A2 response element (A2RE). hnRNP A3 is also a RNA trafficking response element-binding protein that participates in the trafficking of A2RE-containing RNA. The hnRNP A subfamily is characterized by 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. The hnRNP D subfamily includes hnRNP D0, hnRNP A/B, hnRNP DL and similar proteins. hnRNP D0 is a UUAG-specific nuclear RNA binding protein that may be involved in pre-mRNA splicing and telomere elongation. hnRNP A/B 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 DL (or hnRNP D-like) is a dual functional protein that possesses DNA- and RNA-binding properties. It has been implicated in mRNA biogenesis at the transcriptional and post-transcriptional levels. All members in this subfamily contain two putative RRMs and a glycine- and tyrosine-rich C-terminus. The family also contains DAZAP1 (Deleted in azoospermia-associated protein 1), RNA-binding protein Musashi homolog Musashi-1, Musashi-2 and similar proteins. They all harbor two RRMs.

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gi 569003374  932 LSSDMSSRELKKRFEVFGEIVECQVLT-----RSkRGqkHGFITFR 972
Cdd:cd12325     6 LSWETTEESLREYFSKYGEVVDCVVMKdpatgRS-RG--FGFVTFK 48

RNA recognition motif (RRM) found in U2-associated protein SR140 and similar proteins; This subgroup corresponds to the RRM of SR140 (also termed U2 snRNP-associated SURP motif-containing protein orU2SURP, or 140 kDa Ser/Arg-rich domain protein) which is a putative splicing factor mainly found in higher eukaryotes. Although it is initially identified as one of the 17S U2 snRNP-associated proteins, the molecular and physiological function of SR140 remains unclear. SR140 contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a SWAP/SURP domain that is found in a number of pre-mRNA splicing factors in the middle region, and a C-terminal arginine/serine-rich domain (RS domain).

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gi 569003374  927 VYIRNLSSDMSSRELKKRFEVFGEIVECQVL---TRSKRGQKH--GFITFRCSEHA--ALSVRNGATLR 988
Cdd:cd12223     4 LYVGNLPPSVTEEVLLREFGRFGPLASVKIMwprTEEERRRNRncGFVAFMSRADAerAMRELNGKDVM 72

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.

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gi 569003374  928 YIRNLSSDMSSRELKKRFEVFGEIVECQVltrsKRGQKHGFITFRCSEHA-----AL--SVRNGATLRKR 990
Cdd:cd12332     5 FVGNLPNDITEEEFKELFQKYGEVSEVFL----NKGKGFGFIRLDTRANAeaakaELdgTPRKGRQLRVR 70