RNA recognition motif;

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gi 281360042    909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK---YGFVTYERAQDAFTAIDtshrdsqiSMYDISFGGRR 982
Cdd:smart00360    2 LFVGNLPPDTTEEELRELFSKFGKVESVRLVRDKETGKskgFAFVEFESEEDAEKALE--------ALNGKELDGRP 70

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 281360042   909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK--YGFVTYERAQDAFTAIDTSH 966
Cdd:TIGR01628  181 LYVKNLDPSVNEDKLRELFAKFGEITSAAVMKDGSGRSrgFAFVNFEKHEDAAKAVEEMN 240

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360042  905 ERRIVYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMKYGFVTYERAQDAFTAIDTSH--RDSQISMYDISFGGRR 982
Cdd:cd12624     1 ERRVVYIGKIRGRMTRSELKDRFSVFGEIEECTIHFREEGDNYGFVTYRYTEDAFAAIENGHklRRPDELPFDLCFGGRR 80

                          90
                  ....*....|.
gi 281360042  983 AFCRSSYADLD 993
Cdd:cd12624    81 QFCKSSYADLD 91

RNA recognition motif (RRM) found in peroxisome proliferator-activated receptor gamma coactivator 1-beta (PGC-1-beta) and similar proteins; This subfamily corresponds to the RRM of PGC-1beta, also termed PPAR-gamma coactivator 1-beta, or PPARGC-1-beta, or PGC-1-related estrogen receptor alpha coactivator, which is one of the members of PGC-1 transcriptional coactivators family, including PGC-1alpha and PGC-1-related coactivator (PRC). PGC-1beta plays a nonredundant role in controlling mitochondrial oxidative energy metabolism and affects both, insulin sensitivity and mitochondrial biogenesis, and functions in a number of oxidative tissues. It is involved in maintaining baseline mitochondrial function and cardiac contractile function following pressure overload hypertrophy by preserving glucose metabolism and preventing oxidative stress. PGC-1beta induces hypertriglyceridemia in response to dietary fats through activating hepatic lipogenesis and lipoprotein secretion. It can stimulate apolipoprotein C3 (APOC3) expression, further mediating hypolipidemic effect of nicotinic acid. PGC-1beta also drives nuclear respiratory factor 1 (NRF-1) target gene expression and NRF-1 and estrogen related receptor alpha (ERRalpha)-dependent mitochondrial biogenesis. The modulation of the expression of PGC-1beta can trigger ERRalpha-induced adipogenesis. PGC-1beta is also a potent regulator inducing angiogenesis in skeletal muscle. The transcriptional activity of PGC-1beta can be increased through binding to host cell factor (HCF), a cellular protein involved in herpes simplex virus (HSV) infection and cell cycle regulation. PGC-1beta is a multi-domain protein containing an N-terminal activation domain, an LXXLL coactivator signature, a tetrapeptide motif (DHDY) responsible for HCF binding, two glutamic/aspartic acid-rich acidic domains, and an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). In contrast to PGC-1alpha, PGC-1beta lacks most of the arginine/serine (SR)-rich domain that is responsible for the regulation of RNA processing.

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gi 281360042  900 QPAVEERRIVYVGRIEQETTKEILRRKFLPYGSIKQITIHYKEN-GMKYGFVTYERAQDAFTAID--TSHRDSQISMYDI 976
Cdd:cd12356     1 EKAIGEGRVVYIRNLSSSMSSNELKRRFEVFGEITECCVLSRSNrGEKYGFITYRDSEHAALSLQkgASLRKRNEPSFQL 80

                          90
                  ....*....|....*..
gi 281360042  977 SFGGRRAFCRSSYADLD 993
Cdd:cd12356    81 SYGGLRHFFWTRYTDLD 97

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 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENG--MKYGFVTYERAQDAFTAIDTshrdsqisMYDISFGGRR 982
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDRDGksKGFAFVEFESPEDAEKALEA--------LNGTELGGRP 68

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

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gi 281360042   909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENG--MKYGFVTYERAQDAFTAIDtshrdsqiSMYDISFGGRR 982
Cdd:pfam00076    1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDETGrsKGFAFVEFEDEEDAEKAIE--------ALNGKELGGRE 68

RNA recognition motif 1 (RRM1) found in (U)-binding-splicing factor PUF60 and similar proteins; This subfamily corresponds to the RRM1 of PUF60, also termed FUSE-binding protein-interacting repressor (FBP-interacting repressor or FIR), or Ro-binding protein 1 (RoBP1), or Siah-binding protein 1 (Siah-BP1). 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 RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal U2AF (U2 auxiliary factor) homology motifs (UHM) that harbors another RRM and binds to tryptophan-containing linear peptide motifs (UHM ligand motifs, ULMs) in several nuclear proteins. Research indicates that PUF60 binds FUSE as a dimer, and only the first two RRM domains participate in the single-stranded DNA recognition.

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gi 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK---YGFVTYERAQDAFTAIDtshrdsqiSMYDISFGGR 981
Cdd:cd12370     3 VYVGSIYFELGEDTIRQAFAPFGPIKSIDMSWDPVTMKhkgFAFVEYEVPEAAQLALE--------QMNGVMLGGR 70

RNA recognition motif 2 (RRM2) found in Drosophila melanogaster Bruno protein and similar proteins; This subgroup corresponds to the RRM2 of Bruno, a Drosophila RNA recognition motif (RRM)-containing protein that plays a central role in regulation of Oskar (Osk) expression. It mediates repression by binding to regulatory Bruno response elements (BREs) in the Osk mRNA 3' UTR. The full-length Bruno protein contains three RRMs, two located in the N-terminal half of the protein and the third near the C-terminus, separated by a linker region.

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gi 281360042  905 ERRIvYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMKYG--FVTYERAQDAFTAIDTSHRdSQ 970
Cdd:cd12636     1 ERKL-FVGMLSKKCNESDVRIMFSPYGSIEECTVLRDQNGKSRGcaFVTFTSRQCAVNAIKAMHH-SQ 66

RNA recognition motif (RRM) found in eukaryotic translation initiation factor 3 subunit B (eIF-3B) and similar proteins; This subfamily corresponds to the RRM domain in eukaryotic translation initiation factor 3 (eIF-3), a large multisubunit complex that plays a central role in the initiation of translation by binding to the 40 S ribosomal subunit and promoting the binding of methionyl-tRNAi and mRNA. eIF-3B, also termed eIF-3 subunit 9, or Prt1 homolog, eIF-3-eta, eIF-3 p110, or eIF-3 p116, is the major scaffolding subunit of eIF-3. It interacts with eIF-3 subunits A, G, I, and J. eIF-3B contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is involved in the interaction with eIF-3J. The interaction between eIF-3B and eIF-3J is crucial for the eIF-3 recruitment to the 40 S ribosomal subunit. eIF-3B also binds directly to domain III of the internal ribosome-entry site (IRES) element of hepatitis-C virus (HCV) RNA through its N-terminal RRM, which may play a critical role in both cap-dependent and cap-independent translation. Additional research has shown that eIF-3B may function as an oncogene in glioma cells and can be served as a potential therapeutic target for anti-glioma therapy. This family also includes the yeast homolog of eIF-3 subunit B (eIF-3B, also termed PRT1 or eIF-3 p90) that interacts with the yeast homologs of eIF-3 subunits A(TIF32), G(TIF35), I(TIF34), J(HCR1), and E(Pci8). In yeast, eIF-3B (PRT1) contains an N-terminal RRM that is directly involved in the interaction with eIF-3A (TIF32) and eIF-3J (HCR1). In contrast to its human homolog, yeast eIF-3B (PRT1) may have potential to bind its total RNA through its RRM domain.

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gi 281360042  901 PAVEERRivyvgrieQETTKEILRRKFLPYGSIKQITIHY--KENGMKYG--FVTYERAQDAFTAIDTSH 966
Cdd:cd12278    10 PVVGEEK--------LEKLKKVLTKIFSKFGSGKIVGIYMpvDETGKTKGfaFVEYATPEEAKKAVKALN 71

RNA recognition motif (RRM) found in Pre-mRNA-splicing factor RBM22 and similar proteins; This subgroup corresponds to the RRM of RBM22 (also known as RNA-binding motif protein 22, or Zinc finger CCCH domain-containing protein 16), a newly discovered RNA-binding motif protein which belongs to the SLT11 gene family. SLT11 gene encoding protein (Slt11p) is a splicing factor in yeast, which is required for spliceosome assembly. Slt11p has two distinct biochemical properties: RNA-annealing and RNA-binding activities. RBM22 is the homolog of SLT11 in vertebrate. It has been reported to be involved in pre-splicesome assembly and to interact with the Ca2+-signaling protein ALG-2. It also plays an important role in embryogenesis. RBM22 contains a conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a zinc finger of the unusual type C-x8-C-x5-C-x3-H, and a C-terminus that is unusually rich in the amino acids Gly and Pro, including sequences of tetraprolines.

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gi 281360042  910 YVGRIEQETTKEILRRKFLPYGSIKQITIHYKENgmkYGFVTYERAQDAFTAIDTSH 966
Cdd:cd12224     5 YVGGLGDKITEKDLRDHFYQFGEIRSITVVARQQ---CAFVQFTTRQAAERAAERTF 58

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

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gi 281360042  907 RIVYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMKYG--FVTYERAQDAFTAIDTSH 966
Cdd:cd12635     2 RKLFVGMLGKQQSEDDVRRLFEPFGSIEECTILRGPDGNSKGcaFVKFSSHAEAQAAINALH 63

RNA recognition motif 1 (RRM1) found in serine/arginine-rich splicing factor 4 (SRSF4) and similar proteins; This subfamily corresponds to the RRM1 in three serine/arginine (SR) proteins: serine/arginine-rich splicing factor 4 (SRSF4 or SRp75 or SFRS4), serine/arginine-rich splicing factor 5 (SRSF5 or SRp40 or SFRS5 or HRS), serine/arginine-rich splicing factor 6 (SRSF6 or SRp55). SRSF4 plays an important role in both, constitutive and alternative, splicing of many pre-mRNAs. It can shuttle between the nucleus and cytoplasm. SRSF5 regulates both alternative splicing and basal splicing. It is the only SR protein efficiently selected from nuclear extracts (NE) by the splicing enhancer (ESE) and essential for enhancer activation. SRSF6 preferentially interacts with a number of purine-rich splicing enhancers (ESEs) to activate splicing of the ESE-containing exon. It is the only protein from HeLa nuclear extract or purified SR proteins that specifically binds B element RNA after UV irradiation. SRSF6 may also recognize different types of RNA sites. Members in this family contain two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a C-terminal RS domains rich in serine-arginine dipeptides.

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gi 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIhykENGmkYGFVTYERAQDAFTAI 962
Cdd:cd12337     2 VYIGRLPYRARERDVERFFRGYGRIRDINL---KNG--FGFVEFEDPRDADDAV 50

RNA recognition motif (RRM) found in heterogeneous nuclear ribonucleoprotein C (hnRNP C)-related proteins; This subfamily corresponds to the RRM in the hnRNP C-related protein family, including hnRNP C proteins, Raly, and Raly-like protein (RALYL). hnRNP C proteins, C1 and C2, are produced by a single coding sequence. They are the major constituents of the heterogeneous nuclear RNA (hnRNA) ribonucleoprotein (hnRNP) complex in vertebrates. They bind hnRNA tightly, suggesting a central role in the formation of the ubiquitous hnRNP complex; they are involved in the packaging of the hnRNA in the nucleus and in processing of pre-mRNA such as splicing and 3'-end formation. Raly, also termed autoantigen p542, is an RNA-binding protein that may play a critical role in embryonic development. The biological role of RALYL remains unclear. It shows high sequence homology with hnRNP C proteins and Raly. Members of this family are characterized by an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal auxiliary domain. The Raly proteins contain a glycine/serine-rich stretch within the C-terminal regions, which is absent in the hnRNP C proteins. Thus, the Raly proteins represent a newly identified class of evolutionarily conserved autoepitopes.

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gi 281360042  906 RRIvYVGRIEQE-TTKEILRRKFLPYGSIKQITIHYKengmkYGFVTYERAQDAFTAID 963
Cdd:cd12341     1 SRI-FVGNLPTDqMTKEDLEEIFSKYGKILGISLHKG-----YGFVQFDNEEDARAAVA 53

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 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK--YGFVTYERAQDAFTAIDTshrdsqisMYDISFGGRRAFC 985
Cdd:cd12380     4 VYVKNFGEDVDDDELKELFEKYGKITSAKVMKDDSGKSkgFGFVNFENHEAAQKAVEE--------LNGKELNGKKLYV 74

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.

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gi 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK--YGFVTYERAQDA 958
Cdd:cd12412     5 IFVGGIDWDTTEEELREFFSKFGKVKDVKIIKDRAGVSkgYGFVTFETQEDA 56

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 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHY-KENGMK--YGFVTYERAQDAFTAID 963
Cdd:cd21608     2 LYVGNLSWDTTEDDLRDLFSEFGEVESAKVITdRETGRSrgFGFVTFSTAEAAEAAID 59

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 281360042   909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK--YGFVTYERAQDAFTAIDTSH 966
Cdd:TIGR01628  181 LYVKNLDPSVNEDKLRELFAKFGEITSAAVMKDGSGRSrgFAFVNFEKHEDAAKAVEEMN 240

poly-U binding splicing factor, half-pint family; The proteins represented by this model contain three RNA recognition motifs (rrm: pfam00076) and have been characterized as poly-pyrimidine tract binding proteins associated with RNA splicing factors. In the case of PUF60 (GP|6176532), in complex with p54, and in the presence of U2AF, facilitates association of U2 snRNP with pre-mRNA.

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gi 281360042   909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK---YGFVTYERAQDAFTAIDtshrdsqiSMYDISFGGR 981
Cdd:TIGR01645  110 VYVGSISFELREDTIRRAFDPFGPIKSINMSWDPATGKhkgFAFVEYEVPEAAQLALE--------QMNGQMLGGR 177

RNA recognition motif 2 (RRM2) found in granule-associated RNA binding proteins p40-TIA-1 and TIAR; This subfamily corresponds to the RRM2 of nucleolysin TIA-1 isoform p40 (p40-TIA-1 or TIA-1) and nucleolysin TIA-1-related protein (TIAR), both of which are granule-associated RNA binding proteins involved in inducing apoptosis in cytotoxic lymphocyte (CTL) target cells. TIA-1 and TIAR share high sequence similarity. They are expressed in a wide variety of cell types. TIA-1 can be phosphorylated by a serine/threonine kinase that is activated during Fas-mediated apoptosis. TIAR is mainly localized in the nucleus of hematopoietic and nonhematopoietic cells. It is translocated from the nucleus to the cytoplasm in response to exogenous triggers of apoptosis. Both, TIA-1 and TIAR, bind specifically to poly(A) but not to poly(C) homopolymers. They are composed of three N-terminal highly homologous RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a glutamine-rich C-terminal auxiliary domain containing a lysosome-targeting motif. TIA-1 and TIAR interact with RNAs containing short stretches of uridylates and their RRM2 can mediate the specific binding to uridylate-rich RNAs. The C-terminal auxiliary domain may be responsible for interacting with other proteins. In addition, TIA-1 and TIAR share a potential serine protease-cleavage site (Phe-Val-Arg) localized at the junction between their RNA binding domains and their C-terminal auxiliary domains.

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gi 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK---YGFVTYERAQDAFTAI 962
Cdd:cd12353     2 IFVGDLSPEIETEDLKEAFAPFGEISDARVVKDTQTGKskgYGFVSFVKKEDAENAI 58

RNA recognition motif (RRM) found in vertebrate RNA binding protein fox-1 homologs and similar proteins; This subfamily corresponds to the RRM of several tissue-specific alternative splicing isoforms of vertebrate RNA binding protein Fox-1 homologs, which show high sequence similarity to the Caenorhabditis elegans feminizing locus on X (Fox-1) gene encoding Fox-1 protein. RNA binding protein Fox-1 homolog 1 (RBFOX1), also termed ataxin-2-binding protein 1 (A2BP1), or Fox-1 homolog A, or hexaribonucleotide-binding protein 1 (HRNBP1), is predominantly expressed in neurons, skeletal muscle and heart. It regulates alternative splicing of tissue-specific exons by binding to UGCAUG elements. Moreover, RBFOX1 binds to the C-terminus of ataxin-2 and forms an ataxin-2/A2BP1 complex involved in RNA processing. RNA binding protein fox-1 homolog 2 (RBFOX2), also termed Fox-1 homolog B, or hexaribonucleotide-binding protein 2 (HRNBP2), or RNA-binding motif protein 9 (RBM9), or repressor of tamoxifen transcriptional activity, is expressed in ovary, whole embryo, and human embryonic cell lines in addition to neurons and muscle. RBFOX2 activates splicing of neuron-specific exons through binding to downstream UGCAUG elements. RBFOX2 also functions as a repressor of tamoxifen activation of the estrogen receptor. RNA binding protein Fox-1 homolog 3 (RBFOX3 or NeuN or HRNBP3), also termed Fox-1 homolog C, is a nuclear RNA-binding protein that regulates alternative splicing of the RBFOX2 pre-mRNA, producing a message encoding a dominant negative form of the RBFOX2 protein. Its message is detected exclusively in post-mitotic regions of embryonic brain. Like RBFOX1, both RBFOX2 and RBFOX3 bind to the hexanucleotide UGCAUG elements and modulate brain and muscle-specific splicing of exon EIIIB of fibronectin, exon N1 of c-src, and calcitonin/CGRP. Members in this family also harbor one RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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gi 281360042  923 LRRKFLPYGSIKQITIHYKENGMK-YGFVTYERAQDA 958
Cdd:cd12407    17 LRQMFGQFGTILDVEIIFNERGSKgFGFVTFANSADA 53

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 281360042  907 RIVYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK---YGFVTYERAQDAFTAID 963
Cdd:cd21615    19 KTLFVGRLDYSLTELELQKKFSKFGEIEKIRIVRDKETGKsrgYAFIVFKSESDAKNAFK 78

RNA recognition motif 2 (RRM2) found in squamous cell carcinoma antigen recognized by T-cells 3 (SART3) and similar proteins; This subfamily corresponds to the RRM2 of SART3, also termed Tat-interacting protein of 110 kDa (Tip110), is an RNA-binding protein expressed in the nucleus of the majority of proliferating cells, including normal cells and malignant cells, but not in normal tissues except for the testes and fetal liver. It is involved in the regulation of mRNA splicing probably via its complex formation with RNA-binding protein with a serine-rich domain (RNPS1), a pre-mRNA-splicing factor. SART3 has also been identified as a nuclear Tat-interacting protein that regulates Tat transactivation activity through direct interaction and functions as an important cellular factor for HIV-1 gene expression and viral replication. In addition, SART3 is required for U6 snRNP targeting to Cajal bodies. It binds specifically and directly to the U6 snRNA, interacts transiently with the U6 and U4/U6 snRNPs, and promotes the reassembly of U4/U6 snRNPs after splicing in vitro. SART3 contains an N-terminal half-a-tetratricopeptide repeat (HAT)-rich domain, a nuclearlocalization signal (NLS) domain, and two C-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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gi 281360042  905 ERRIVYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMKYG--FVTYERAQDAFTAI 962
Cdd:cd12392     1 EKNKLFVKGLPFSCTKEELEELFKQHGTVKDVRLVTYRNGKPKGlaYVEYENEADASQAV 60

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 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIhYKEngmkYGFVTYERAQDAFTAI 962
Cdd:cd12607     3 LHVGNISSSCTNQELRAKFEEYGPVIECDI-VKD----YAFVHMERAEDAMEAI 51

RNA recognition motif (RRM) found in vertebrate RNA-binding protein 11 (RBM11); This subfamily corresponds to the RRM or RBM11, a novel tissue-specific splicing regulator that is selectively expressed in brain, cerebellum and testis, and to a lower extent in kidney. RBM11 is localized in the nucleoplasm and enriched in SRSF2-containing splicing speckles. It may play a role in the modulation of alternative splicing during neuron and germ cell differentiation. RBM11 contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a region lacking known homology at the C-terminus. The RRM of RBM11 is responsible for RNA binding, whereas the C-terminal region permits nuclear localization and homodimerization.

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gi 281360042  907 RIVYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK--YGFVTYERAQDAFTAI 962
Cdd:cd12593     2 RTVFVGNLHSNVNEEILYELFLQAGPLTKVTIAKDKEGKPksFGFVCFKHAESVPYAI 59

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.

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gi 281360042  909 VYVGRIEQETTKEILRRKFLPYGSIKQITIHYKENGMK---YGFVTYERAQDAFTAI 962
Cdd:cd12377     2 IFVYNLAPDADESLLWQLFGPFGAVQNVKIIRDFTTNKckgYGFVTMTNYDEAAVAI 58