RNA recognition motif 2 (RRM2) found in serine/arginine-rich splicing factor 4 (SRSF4) and similar proteins; This subfamily corresponds to the RRM2 of 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 is 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1605510877  29 YRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVED 100
Cdd:cd12600     1 YRLIVENLSSRVSWQDLKDYMRQAGEVTYADAHKQRKNEGVVEFASYSDMKNAIEKLDGTELNGRKIRLVED 72

RNA recognition motif 2 (RRM2) found in serine/arginine-rich splicing factor 4 (SRSF4) and similar proteins; This subfamily corresponds to the RRM2 of 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 is 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1605510877  29 YRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVED 100
Cdd:cd12600     1 YRLIVENLSSRVSWQDLKDYMRQAGEVTYADAHKQRKNEGVVEFASYSDMKNAIEKLDGTELNGRKIRLVED 72

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1605510877   30 RLIVENLSSRCSWQDLKDYMRQAGEVTYA----DAHKGR-KNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRL 97
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVESVrlvrDKETGKsKGFAFVEFESEEDAEKALEALNGKELDGRPLKV 73

U2 snRNP auxilliary factor, large subunit, splicing factor; These splicing factors consist of an N-terminal arginine-rich low complexity domain followed by three tandem RNA recognition motifs (pfam00076). The well-characterized members of this family are auxilliary components of the U2 small nuclear ribonuclearprotein splicing factor (U2AF). These proteins are closely related to the CC1-like subfamily of splicing factors (TIGR01622). Members of this subfamily are found in plants, metazoa and fungi.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1605510877 170 EKSRSPSKD-NKSRSRSRSPDKSRSKSKDHAEDKlqnndsagkakshSPSRHDSKSRSRSQERRAEEERRRSVSRARSQE 248
Cdd:TIGR01642  10 EKSRGRDRDrSSERPRRRSRDRSRFRDRHRRSRE-------------RSYREDSRPRDRRRYDSRSPRSLRYSSVRRSRD 76

                          90       100       110
                  ....*....|....*....|....*....|...
gi 1605510877 249 KSRSQEKSllkSRSRSRSKVGSRSRSRSKDKRK 281
Cdd:TIGR01642  77 RPRRRSRS---VRSIEQHRRRLRDRSPSNQWRK 106

RNA recognition motif 2 (RRM2) found in serine/arginine-rich splicing factor 4 (SRSF4) and similar proteins; This subfamily corresponds to the RRM2 of 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 is 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1605510877  29 YRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVED 100
Cdd:cd12600     1 YRLIVENLSSRVSWQDLKDYMRQAGEVTYADAHKQRKNEGVVEFASYSDMKNAIEKLDGTELNGRKIRLVED 72

RNA recognition motif 2 (RRM2) found in serine/arginine-rich splicing factor SRSF1, SRSF4 and similar proteins; This subfamily corresponds to the RRM2 of several serine/arginine (SR) proteins that have been classified into two subgroups. The first subgroup consists of serine/arginine-rich splicing factor 4 (SRSF4 or SRp75 or SFRS4), serine/arginine-rich splicing factor 5 (SRSF5 or SRp40 or SFRS5 or HRS) and serine/arginine-rich splicing factor 6 (SRSF6 or SRp55). The second subgroup is composed of serine/arginine-rich splicing factor 1 (SRSF1 or ASF-1), serine/arginine-rich splicing factor 9 (SRSF9 or SRp30C) and plant pre-mRNA-splicing factor SF2 (SR1). These SR proteins are mainly involved in regulating constitutive and alternative pre-mRNA splicing. They also have been implicated in transcription, genomic stability, mRNA export and translation. All SR proteins in this family, except SRSF5, undergo nucleocytoplasmic shuttling, suggesting their widespread roles in gene expression. These SR proteins share a common domain architecture comprising 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. Both domains can directly contact with RNA. The RRMs appear to determine the binding specificity and the SR domain also mediates protein-protein interactions. In addition, this subfamily includes the yeast nucleolar protein 3 (Npl3p), also termed mitochondrial targeting suppressor 1 protein, or nuclear polyadenylated RNA-binding protein 1. It is a major yeast RNA-binding protein that competes with 3'-end processing factors, such as Rna15, for binding to the nascent RNA, protecting the transcript from premature termination and coordinating transcription termination and the packaging of the fully processed transcript for export. It specifically recognizes a class of G/U-rich RNAs. Npl3p is a multi-domain protein with two RRMs, separated by a short linker and a C-terminal domain rich in glycine, arginine and serine residues.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1605510877  29 YRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLV 98
Cdd:cd12339     1 FRVVVSNLPERASWQDLKDFMRKAGEVTYADVHRDREGEGVVEFTSEEDMKRAIEKLDGTEFNGRRIRVE 70

RNA recognition motif 2 (RRM2) found in vertebrate serine/arginine-rich splicing factor 5 (SRSF5); This subgroup corresponds to the RRM2 of SRSF5, also termed delayed-early protein HRS, or pre-mRNA-splicing factor SRp40, or splicing factor, arginine/serine-rich 5 (SFRS5), is an essential splicing regulatory serine/arginine (SR) protein that 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 it is necessary for enhancer activation. SRSF5 also functions as a factor required for insulin-regulated splice site selection for protein kinase C (PKC) betaII mRNA. It is involved in the regulation of PKCbetaII exon inclusion by insulin via its increased phosphorylation by a phosphatidylinositol 3-kinase (PI 3-kinase) signaling pathway. Moreover, SRSF5 can regulate alternative splicing in exon 9 of glucocorticoid receptor pre-mRNA in a dose-dependent manner. SRSF5 contains 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. The specific RNA binding by SRSF5 requires the phosphorylation of its SR domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1605510877  23 PPTRTEYRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVE 99
Cdd:cd12765     4 PPMRTENRLIVENLSSRVSWQDLKDFMRQAGEVTFADAHRPKLNEGVVEFASYSDLKNAIEKLSGKEINGRKIKLIE 80

RNA recognition motif 2 (RRM2) found in serine/arginine-rich splicing factor SRSF1, SRSF9 and similar proteins; This subfamily corresponds to the RRM2 of serine/arginine-rich splicing factor SRSF1, SRSF9 and similar proteins. SRSF1, also termed ASF-1, is a shuttling SR protein involved in constitutive and alternative splicing, nonsense-mediated mRNA decay (NMD), mRNA export and translation. It also functions as a splicing-factor oncoprotein that regulates apoptosis and proliferation to promote mammary epithelial cell transformation. SRSF9, also termed SRp30C, has been implicated in the activity of many elements that control splice site selection, the alternative splicing of the glucocorticoid receptor beta in neutrophils and in the gonadotropin-releasing hormone pre-mRNA. SRSF9 can also interact with other proteins implicated in alternative splicing, including YB-1, rSLM-1, rSLM-2, E4-ORF4, Nop30, and p32. Both, SRSF1 and SRSF9, contain two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RS domains rich in serine-arginine dipeptides.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1605510877  29 YRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHkgRKNEGVIEFVSYSDMKRALEKLDGTE 89
Cdd:cd12601     1 YRVIVSGLPPTGSWQDLKDHMREAGDVCYADVY--RDGTGVVEFLRYEDMKYAVRKLDDSK 59

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 1605510877  31 LIVENLSSRCSWQDLKDYMRQAGEVTYA----DAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRL 97
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGEVVSVrivrDRDGKSKGFAFVEFESPEDAEKALEALNGTELGGRPLKV 71

RNA recognition motif 1 (RRM1) found in Saccharomyces cerevisiae protein HRB1, G-strand-binding protein 2 (GBP2) and similar proteins; The family includes Saccharomyces cerevisiae protein HRB1 (also called protein TOM34) and GBP2, both of which are SR-like mRNA-binding proteins which shuttle from the nucleus to the cytoplasm when bound to the mature mRNA molecules. They act as quality control factors for spliced mRNAs. GBP2, also called RAP1 localization factor 6, is a single-strand telomeric DNA-binding protein that binds single-stranded telomeric sequences of the type (TG[1-3])n in vitro. It also binds to RNA. GBP2 influences the localization of RAP1 in the nuclei and plays a role in modulating telomere length. 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 1605510877  28 EYRLIVENLSSRCSWQDLKDYMRQAGEVTYAD--AHKGR-KNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVED 100
Cdd:cd21605     1 ENSIFVGNLPFDCTWEDLKDHFSQVGEVIRADivTSRGRhRGMGTVEFTNKEDVDRAISKFDHTMFMGREIFVRQD 76

RNA recognition motif 2 (RRM2) found in vertebrate serine/arginine-rich splicing factor 9 (SRSF9); This subgroup corresponds to the RRM2 of SRSF9, also termed pre-mRNA-splicing factor SRp30C, an essential splicing regulatory serine/arginine (SR) protein that has been implicated in the activity of many elements that control splice site selection, the alternative splicing of the glucocorticoid receptor beta in neutrophils and in the gonadotropin-releasing hormone pre-mRNA. SRSF9 can also interact with other proteins implicated in alternative splicing, including YB-1, rSLM-1, rSLM-2, E4-ORF4, Nop30, and p32. SRSF9 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by an unusually short C-terminal RS domains rich in serine-arginine dipeptides.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1605510877  22 GPPTR-TEYRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKgrKNEGVIEFVSYSDMKRALEKLDGTE 89
Cdd:cd12768     1 GPPSRrSEFRVLVSGLPPSGSWQDLKDHMREAGDVCYADVQK--DGMGIVEFLRKEDMEYALRKLDDTK 67

RNA recognition motif (RRM) domain [Translation, ribosomal structure and biogenesis];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1605510877  30 RLIVENLSSRCSWQDLKDYMRQAGEVTYA----DAHKGR-KNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVEDKP 102
Cdd:COG0724     3 KIYVGNLPYSVTEEDLRELFSEYGEVTSVklitDRETGRsRGFGFVEMPDDEEAQAAIEALNGAELMGRTLKVNEARP 80

RNA recognition motif 2 (RRM2) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM2 of RBM28 and Nop4p. RBM28 is a specific nucleolar component of the spliceosomal small nuclear ribonucleoproteins (snRNPs), possibly coordinating their transition through the nucleolus. It specifically associates with U1, U2, U4, U5, and U6 small nuclear RNAs (snRNAs), and may play a role in the maturation of both small nuclear and ribosomal RNAs. RBM28 has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an extremely acidic region between RRM2 and RRM3. The family also includes nucleolar protein 4 (Nop4p or Nop77p) encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p also contains four RRMs.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1605510877  30 RLIVENLSSRCSWQDLKDYMRQAGEVTyaDAHKGRKNEG------VIEFVSYSDMKRALEKLDGTEVNGRKI 95
Cdd:cd12414     1 RLIVRNLPFKCTEDDLKKLFSKFGKVL--EVTIPKKPDGklrgfaFVQFTNVADAAKAIKGMNGKKIKGRPV 70

RNA recognition motif 1 (RRM1) found in vertebrate myelin expression factor 2 (MEF-2); This subgroup corresponds to the RRM1 of MEF-2, also termed MyEF-2 or MST156, a sequence-specific single-stranded DNA (ssDNA) binding protein that binds specifically to ssDNA derived from the proximal (MB1) element of the myelin basic protein (MBP) promoter and represses transcription of the MBP gene. MEF-2 contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which may be responsible for its ssDNA binding activity.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1605510877  30 RLIVENLSSRCSWQDLKDYMRQ-AGEVTYA----DAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVED 100
Cdd:cd12658     1 RVFISNIPYDMKWQAIKDLMREkVGEVTYVelfkDAEGKSRGCGVVEFKDEEFVKKALEVMNKYDLSGRPLNIKED 76

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).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1605510877  30 RLIVENLSSRCSWQDLKDYMRQAGEVTYADA---HKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKI 95
Cdd:cd12407     2 RLHVSNIPFRFRDPDLRQMFGQFGTILDVEIifnERGSKGFGFVTFANSADADRAREKLNGTVVEGRKI 70

RNA recognition motif 1 (RRM1) found in chloroplastic plastid-specific 30S ribosomal protein 2 (PSRP-2) and similar proteins; PSRP-2, also called chloroplastic 30S ribosomal protein 2, or chloroplastic small ribosomal subunit protein cS22, is a component of the chloroplast ribosome (chloro-ribosome), a dedicated translation machinery responsible for the synthesis of chloroplast genome-encoded proteins, including proteins of the transcription and translation machinery and components of the photosynthetic apparatus. It binds single strand DNA (ssDNA) and RNA in vitro. It exhibits RNA chaperone activity and regulates negatively resistance responses to abiotic stresses during seed germination (e.g. salt, dehydration, and low temperature) and seedling growth (e.g. salt). The family also includes Nicotiana sylvestris chloroplastic 33 kDa ribonucleoprotein (NsCP33) and Arabidopsis thaliana chloroplastic 31 kDa ribonucleoprotein (AtCP31A). 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. 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 first RRM motif.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1605510877  30 RLIVENLSSRCSWQDLKDYMRQAG-----EVTYaDAHKGR-KNEGVIEFVSYSDMKRALEKLDGTEVNGRKIR 96
Cdd:cd21609     1 RLYVGNIPRNVTSEELAKIFEEAGtveiaEVMY-DRYTGRsRGFGFVTMGSVEDAKAAIEKLNGTEVGGREIK 72

RNA recognition motif 2 (RRM2) found in vertebrate nucleolin; This subfamily corresponds to the RRM2 of ubiquitously expressed protein nucleolin, also termed protein C23, a multifunctional major nucleolar phosphoprotein that has been implicated in various metabolic processes, such as ribosome biogenesis, cytokinesis, nucleogenesis, cell proliferation and growth, cytoplasmic-nucleolar transport of ribosomal components, transcriptional repression, replication, signal transduction, inducing chromatin decondensation, etc. Nucleolin exhibits intrinsic self-cleaving, DNA helicase, RNA helicase and DNA-dependent ATPase activities. It can be phosphorylated by many protein kinases, such as the major mitotic kinase Cdc2, casein kinase 2 (CK2), and protein kinase C-zeta. Nucleolin shares similar domain architecture with gar2 from Schizosaccharomyces pombe and NSR1 from Saccharomyces cerevisiae. The highly phosphorylated N-terminal domain of nucleolin is made up of highly acidic regions separated from each other by basic sequences, and contains multiple phosphorylation sites. The central domain of nucleolin contains four closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which suggests that nucleolin is potentially able to interact with multiple RNA targets. The C-terminal RGG (or GAR) domain of nucleolin is rich in glycine, arginine and phenylalanine residues, and contains high levels of NG,NG-dimethylarginines.RRM2, together with RRM1, binds specifically to RNA stem-loops containing the sequence (U/G)CCCG(A/G) in the loop.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1605510877  31 LIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGR-KNEGVIEFVSYSDMKRALEKLDGTEVNGRKI 95
Cdd:cd12404     6 LFVKNLPYSTTQDELKEVFEDAVDIRIPMGRDGRsKGIAYIEFKSEAEAEKALEEKQGTEVDGRSI 71

RNA recognition motif 3 (RRM3) found in yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8 and similar proteins; This subfamily corresponds to the RRM3 of NGR1 and NAM8. NGR1, also termed RNA-binding protein RBP1, is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA) in yeast. It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the carboxyl terminus which also harbors a methionine-rich region. The family also includes protein NAM8, which is a putative RNA-binding protein that acts as a suppressor of mitochondrial splicing deficiencies when overexpressed in yeast. It may be a non-essential component of the mitochondrial splicing machinery. Like NGR1, NAM8 contains two RRMs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1605510877  33 VENLSSRCSWQDLKDYMRQAGEVTYADAHKGrKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRL 97
Cdd:cd12346     6 VGGLDPNVTEEDLRVLFGPFGEIVYVKIPPG-KGCGFVQFVNRASAEAAIQKLQGTPIGGSRIRL 69

RNA recognition motif 3 (RRM3) found in vertebrate myelin expression factor 2 (MEF-2); This subgroup corresponds to the RRM3 of MEF-2, also termed MyEF-2 or MST156, a sequence-specific single-stranded DNA (ssDNA) binding protein that binds specifically to ssDNA derived from the proximal (MB1) element of the myelin basic protein (MBP) promoter and represses transcription of the MBP gene. MEF-2 contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which may be responsible for its ssDNA binding activity.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1605510877  30 RLIVENLSSRCSWQDLKDYMRQAGEVTYAD---AHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRLVEDK 101
Cdd:cd12662     1 QIFVRNLPFDLTWQKLKEKFSQCGHVMFAEikmENGKSKGCGTVRFDSPESAEKACRLMNGIKISGREIDVRLDR 75

RNA recognition motif 2 (RRM2) found in vertebrate RNA-binding protein RBM23, RBM39 and similar proteins; This subfamily corresponds to the RRM2 of RBM39 (also termed HCC1), a nuclear autoantigen that contains an N-terminal arginine/serine rich (RS) motif and three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). An octapeptide sequence called the RS-ERK motif is repeated six times in the RS region of RBM39. Although the cellular function of RBM23 remains unclear, it shows high sequence homology to RBM39 and contains two RRMs. It may possibly function as a pre-mRNA splicing factor.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1605510877  31 LIVENLSSRCSWQDLKDYMRQAGEVTYADAHK----GR-KNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRL 97
Cdd:cd12284     1 LYVGSLHFNITEDMLRGIFEPFGKIEFVQLQKdpetGRsKGYGFIQFRDAEDAKKALEQLNGFELAGRPMKV 72

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 1605510877  31 LIVENLSSRCSWQDLKDYMRQAGEVTYAD-----AHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRL 97
Cdd:cd12417     2 LWISGLSDTTKAADLKKIFSKYGKVVSAKvvtsaRTPGSRCYGYVTMASVEEADLCIKSLNKTELHGRVITV 73

RNA recognition motif 3 (RRM3) found in SMART/HDAC1-associated repressor protein (SHARP) and similar proteins; This subfamily corresponds to the RRM3 of SHARP, also termed Msx2-interacting protein (MINT), or SPEN homolog, an estrogen-inducible transcriptional repressor that interacts directly with the nuclear receptor corepressor SMRT, histone deacetylases (HDACs) and components of the NuRD complex. SHARP recruits HDAC activity and binds to the steroid receptor RNA coactivator SRA through four conserved N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), further suppressing SRA-potentiated steroid receptor transcription activity. Thus, SHARP has the capacity to modulate both liganded and nonliganded nuclear receptors. SHARP also has been identified as a component of transcriptional repression complexes in Notch/RBP-Jkappa signaling pathways. In addition to the N-terminal RRMs, SHARP possesses a C-terminal SPOC domain (Spen paralog and ortholog C-terminal domain), which is highly conserved among Spen proteins.

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gi 1605510877  25 TRTeyrLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGViEFVSYSDMK---RALEKLDGTEVNGRKIRL 97
Cdd:cd12350     2 TRT---LFIGNLEKTTTYGDLRNIFERFGEIIDIDIKKQNGNPQY-AFLQYCDIAsvvKAIKKMDGEYLGNNRLKL 73

RNA recognition motif 2 (RRM2) found in plant Mei2-like proteins; This subgroup corresponds to the RRM2 of Mei2-like proteins that represent an ancient eukaryotic RNA-binding proteins family. Their corresponding Mei2-like genes appear to have arisen early in eukaryote evolution, been lost from some lineages such as Saccharomyces cerevisiae and metazoans, and diversified in the plant lineage. The plant Mei2-like genes may function in cell fate specification during development, rather than as stimulators of meiosis. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The C-terminal RRM (RRM3) is unique to Mei2-like proteins and is highly conserved between plants and fungi. To date, the intracellular localization, RNA target(s), cellular interactions and phosphorylation states of Mei2-like proteins in plants remain unclear.

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gi 1605510877  31 LIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKIRL 97
Cdd:cd12529     4 LVVFNLDPSISNDDLHQIFGAYGEIKEIRETPNKRHHKFIEFYDVRSAEAALKALNKSEIAGKRIKL 70

U2 snRNP auxilliary factor, large subunit, splicing factor; These splicing factors consist of an N-terminal arginine-rich low complexity domain followed by three tandem RNA recognition motifs (pfam00076). The well-characterized members of this family are auxilliary components of the U2 small nuclear ribonuclearprotein splicing factor (U2AF). These proteins are closely related to the CC1-like subfamily of splicing factors (TIGR01622). Members of this subfamily are found in plants, metazoa and fungi.

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gi 1605510877 170 EKSRSPSKD-NKSRSRSRSPDKSRSKSKDHAEDKlqnndsagkakshSPSRHDSKSRSRSQERRAEEERRRSVSRARSQE 248
Cdd:TIGR01642  10 EKSRGRDRDrSSERPRRRSRDRSRFRDRHRRSRE-------------RSYREDSRPRDRRRYDSRSPRSLRYSSVRRSRD 76

                          90       100       110
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gi 1605510877 249 KSRSQEKSllkSRSRSRSKVGSRSRSRSKDKRK 281
Cdd:TIGR01642  77 RPRRRSRS---VRSIEQHRRRLRDRSPSNQWRK 106

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 1605510877  30 RLIVENLSSRCSWQDLKDYMRQAGEVTYADAhkgRKNEGVIEFVSYSDMKRALEKLDGTEVNGRKI 95
Cdd:cd12343     1 KIFVGNLPDAATSEELRALFEKYGKVTECDI---VKNYAFVHMEKEEDAEDAIKALNGYEFMGSRI 63

RNA recognition motif 2 (RRM2) found in vertebrate RRM-containing coactivator activator/modulator (CoAA); This subgroup corresponds to the RRM2 of CoAA, also termed RNA-binding protein 14 (RBM14), or paraspeckle protein 2 (PSP2), or synaptotagmin-interacting protein (SYT-interacting protein), 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. It stimulates transcription through its interactions with coactivators, such as TRBP and CREB-binding protein CBP/p300, via the TRBP-interacting domain and interaction with an RNA-containing complex, such as DNA-dependent protein kinase-poly(ADP-ribose) polymerase complexes, via the RRMs.

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gi 1605510877  29 YRLIVENLSSRCSWQDLKDYMRQAGEVTYADAHKGRkneGVIEFVSYSDMKRALEKLDGTEVNGRKI 95
Cdd:cd12609     1 WKIFVGNVSATCTSDELRGLFEEFGRVVECDKVKDY---AFVHMEREEEALAAIEALNGKEVKGRRI 64

RNA recognition motif 2 (RRM2) found in splicing regulatory glutamine/lysine-rich protein 1 (SREK1) and similar proteins; This subfamily corresponds to the RRM2 of SREK1, also termed serine/arginine-rich-splicing regulatory protein 86-kDa (SRrp86), or splicing factor arginine/serine-rich 12 (SFRS12), or splicing regulatory protein 508 amino acid (SRrp508). SREK1 belongs to a family of proteins containing regions rich in serine-arginine dipeptides (SR proteins family), which is involved in bridge-complex formation and splicing by mediating protein-protein interactions across either introns or exons. It is a unique SR family member and it may play a crucial role in determining tissue specific patterns of alternative splicing. SREK1 can alter splice site selection by both positively and negatively modulating the activity of other SR proteins. For instance, SREK1 can activate SRp20 and repress SC35 in a dose-dependent manner both in vitro and in vivo. In addition, SREK1 contains two (some contain only one) RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and two serine-arginine (SR)-rich domains (SR domains) separated by an unusual glutamic acid-lysine (EK) rich region. The RRM and SR domains are highly conserved among other members of the SR superfamily. However, the EK domain is unique to SREK1. It plays a modulatory role controlling SR domain function by involvement in the inhibition of both constitutive and alternative splicing and in the selection of splice-site.

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gi 1605510877  26 RTeyrLIVENLSSRCSWQDLKDYMRQAGEVTY---ADAHKGRKNEGVIEFVSYSDMKRALeKLDGTEVNGRKI 95
Cdd:cd12260     5 RT---VYVGNLDPSTTADQLLEFFSQAGEVKYvrmAGDETQPTRYAFVEFAEQTSVINAL-KLNGKMFGGRPL 73