RNA recognition motif in type II polyadenylate-binding protein 2 (PABP-2) and similar proteins; This subgroup corresponds to the RRM of PABP-2, also termed poly(A)-binding protein 2, or nuclear poly(A)-binding protein 1 (PABPN1), or poly(A)-binding protein II (PABII), which is a ubiquitously expressed type II nuclear poly(A)-binding protein that directs the elongation of mRNA poly(A) tails during pre-mRNA processing. Although PABP-2 binds poly(A) with high affinity and specificity as type I poly(A)-binding proteins, it contains only one highly conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is responsible for the poly(A) binding. In addition, PABP-2 possesses an acidic N-terminal domain that is essential for the stimulation of PAP, and an arginine-rich C-terminal domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKVIPKR 120
Cdd:cd12550     1 SVYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFADKESVRTALALDESLFRGRQIKVMPKR 76

RNA recognition motif in type II polyadenylate-binding protein 2 (PABP-2) and similar proteins; This subgroup corresponds to the RRM of PABP-2, also termed poly(A)-binding protein 2, or nuclear poly(A)-binding protein 1 (PABPN1), or poly(A)-binding protein II (PABII), which is a ubiquitously expressed type II nuclear poly(A)-binding protein that directs the elongation of mRNA poly(A) tails during pre-mRNA processing. Although PABP-2 binds poly(A) with high affinity and specificity as type I poly(A)-binding proteins, it contains only one highly conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is responsible for the poly(A) binding. In addition, PABP-2 possesses an acidic N-terminal domain that is essential for the stimulation of PAP, and an arginine-rich C-terminal domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKVIPKR 120
Cdd:cd12550     1 SVYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFADKESVRTALALDESLFRGRQIKVMPKR 76

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:COG0724     3 KIYVGNLPYSVTEEDLRELFSEYGEVTSVKLITDRETGRSRGFGFVEMPDDEEAQAAIeALNGAELMGRTLKV 75

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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1339869051  36 EEKMEADARSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIK 115
Cdd:TIGR01622 107 LTEDERDRRTVFVQQLAARARERDLYEFFSKVGKVRDVQIIKDRNSRRSKGVGYVEFYDVDSVQAALALTGQKLLGIPVI 186

                  ...
gi 1339869051 116 VIP 118
Cdd:TIGR01622 187 VQL 189

RNA recognition motif in type II polyadenylate-binding protein 2 (PABP-2) and similar proteins; This subgroup corresponds to the RRM of PABP-2, also termed poly(A)-binding protein 2, or nuclear poly(A)-binding protein 1 (PABPN1), or poly(A)-binding protein II (PABII), which is a ubiquitously expressed type II nuclear poly(A)-binding protein that directs the elongation of mRNA poly(A) tails during pre-mRNA processing. Although PABP-2 binds poly(A) with high affinity and specificity as type I poly(A)-binding proteins, it contains only one highly conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is responsible for the poly(A) binding. In addition, PABP-2 possesses an acidic N-terminal domain that is essential for the stimulation of PAP, and an arginine-rich C-terminal domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKVIPKR 120
Cdd:cd12550     1 SVYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFADKESVRTALALDESLFRGRQIKVMPKR 76

RNA recognition motif in vertebrate type II embryonic polyadenylate-binding protein 2 (ePABP-2); This subgroup corresponds to the RRM of ePABP-2, also termed embryonic poly(A)-binding protein 2, or poly(A)-binding protein nuclear-like 1 (PABPN1L). ePABP-2 is a novel embryonic-specific cytoplasmic type II poly(A)-binding protein that is expressed during the early stages of vertebrate development and in adult ovarian tissue. It may play an important role in the poly(A) metabolism of stored mRNAs during early vertebrate development. ePABP-2 shows significant sequence similarity to the ubiquitously expressed nuclear polyadenylate-binding protein 2 (PABP-2 or PABPN1). Like PABP-2, ePABP-2 contains one RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is responsible for the poly(A) binding. In addition, it possesses an acidic N-terminal domain predicted to form a coiled-coil and an arginine-rich C-terminal domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKVIPKRT 121
Cdd:cd12551     1 SVYVGNVDYGSTADELEAHFNGCGPINRVTILCDKFSGHPKGYAYIEFATRSSVQAAVALDESSFRGRVIKVLPKRT 77

RNA recognition motif (RRM) found in Saccharomyces cerevisiae nucleolar protein 6 (Nop6) and similar proteins; This subfamily corresponds to the RRM of Nop6, also known as Ydl213c, a component of 90S pre-ribosomal particles in yeast S. cerevisiae. It is enriched in the nucleolus and is required for 40S ribosomal subunit biogenesis. Nop6 is a non-essential putative RNA-binding protein with two N-terminal putative nuclear localisation sequences (NLS-1 and NLS-2) and an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It binds to the pre-rRNA early during transcription and plays an essential role in pre-rRNA processing.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKV 116
Cdd:cd12400     3 LFVGNLPYDTTAEDLKEHFKKAGEPPSVRLLTDKKTGKSKGCAFVEFDNQKALQKALKLHHTSLGGRKINV 73

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:COG0724     3 KIYVGNLPYSVTEEDLRELFSEYGEVTSVKLITDRETGRSRGFGFVEMPDDEEAQAAIeALNGAELMGRTLKV 75

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1339869051  44 RSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKES----VRTslaLDESLFRGRQIKV 116
Cdd:cd12398     1 RSVFVGNIPYDATEEQLKEIFSEVGPVVSFRLVTDRETGKPKGYGFCEFRDAETalsaVRN---LNGYELNGRPLRV 74

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:cd21608     2 LYVGNLSWDTTEDDLRDLFSEFGEVESAKVITDRETGRSRGFGFVTFSTAEAAEAAIdALNGKELDGRSIVV 73

RNA recognition motif 2 (RRM2) found in yeast protein gar2 and similar proteins; This subfamily corresponds to the RRM2 of yeast protein gar2, a novel nucleolar protein required for 18S rRNA and 40S ribosomal subunit accumulation. It shares similar domain architecture with nucleolin from vertebrates and NSR1 from Saccharomyces cerevisiae. The highly phosphorylated N-terminal domain of gar2 is made up of highly acidic regions separated from each other by basic sequences, and contains multiple phosphorylation sites. The central domain of gar2 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The C-terminal RGG (or GAR) domain of gar2 is rich in glycine, arginine and phenylalanine residues.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:cd12448     1 LFVGNLPFSATQDALYEAFSQHGSIVSVRLPTDRETGQPKGFGYVDFSTIDSAEAAIdALGGEYIDGRPIRL 72

RNA recognition motif 2 (RRM2) found in nucleolin-like proteins mainly from plants; This subfamily corresponds to the RRM2 of a group of plant nucleolin-like proteins, including nucleolin 1 (also termed protein nucleolin like 1) and nucleolin 2 (also termed protein nucleolin like 2, or protein parallel like 1). They play roles in the regulation of ribosome synthesis and in the growth and development of plants. Like yeast nucleolin, nucleolin-like proteins possess two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1339869051  45 SIYVGNVDYG----ATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKV 116
Cdd:cd12451     1 TIFVKGFDASlgedTIRDELREHFGECGEVTNVRIPTDRETGELKGFAYIEFSTKEAKEKALELNGSDIAGGNLVV 76

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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDkFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIK 115
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRD-ETGRSKGFAFVEFEDEEDAEKAIeALNGKELGGRELK 70

RNA recognition motif 2 (RRM2) found in Arabidopsis thaliana phragmoplastin interacting protein 1 (PHIP1) and similar proteins; The CD corresponds to the RRM2 of PHIP1. A. thaliana PHIP1 and its homologs represent a novel class of plant-specific RNA-binding proteins that may play a unique role in the polarized mRNA transport to the vicinity of the cell plate. The family members consist of multiple functional domains, including a lysine-rich domain (KRD domain) that contains three nuclear localization motifs (KKKR/NK), two RNA recognition motifs (RRMs), and three CCHC-type zinc fingers. PHIP1 is a peripheral membrane protein and is localized at the cell plate during cytokinesis in plants. In addition to phragmoplastin, PHIP1 interacts with two Arabidopsis small GTP-binding proteins, Rop1 and Ran2. However, PHIP1 interacted only with the GTP-bound form of Rop1 but not the GDP-bound form. It also binds specifically to Ran2 mRNA.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKV 116
Cdd:cd12272     1 TVYIGNLAWDIDEDDLRELFAECCEITNVRLHTDKETGEFKGYGHVEFADEESLDAALKLAGTKLCGRPIRV 72

RNA recognition motif 2 (RRM2) found in Arabidopsis thaliana CTC-interacting domain protein CID8, CID9, CID10, CID11, CID12, CID 13 and similar proteins; This subgroup corresponds to the RRM2 domains found in A. thaliana CID8, CID9, CID10, CID11, CID12, CID 13 and mainly their plant homologs. These highly related RNA-binding proteins contain an N-terminal PAM2 domain (PABP-interacting motif 2), two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a basic region that resembles a bipartite nuclear localization signal. The biological role of this family remains unclear.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1339869051  43 ARSIYVGNVDYGATAEELEAHFHG-CGSVNRVTILCDkfSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKVIPKRT 121
Cdd:cd12460     4 ARTIYCTNIDKKVTQDDVKAFFESlCGEVHRLRLLGD--YVHSTRIAFVEFVMAESAIAALNCSGALLGSLPIRVSPSKT 81

RNA recognition motif 1 (RRM1) found in squamous cell carcinoma antigen recognized by T-cells 3 (SART3) and similar proteins; This subfamily corresponds to the RRM1 of SART3, also termed Tat-interacting protein of 110 kDa (Tip110), 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).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDkFSGHPKGFAYIEFSDKESVRTSLALDESLFRGR 112
Cdd:cd12391     1 TVFVSNLDYSVPEDKIREIFSGCGEITDVRLVKN-YKGKSKGYCYVEFKDEESAQKALKLDRQPVEGR 67

RNA recognition motif (RRM) found in eukaryotic translation initiation factor 4H (eIF-4H) and similar proteins; This subfamily corresponds to the RRM of eIF-4H, also termed Williams-Beuren syndrome chromosomal region 1 protein, which, together with elf-4B/eIF-4G, serves as the accessory protein of RNA helicase eIF-4A. eIF-4H contains a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It stimulates protein synthesis by enhancing the helicase activity of eIF-4A in the initiation step of mRNA translation.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1339869051  47 YVGNVDYGATAEELEAHFHGCgSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKV 116
Cdd:cd12401     9 YVGNLPFNTVQGDLDAIFKDL-KVRSVRLVRDRETDKFKGFCYVEFEDLESLKEALEYDGALFEDRPLRV 77

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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1339869051  42 DARSIYVGNVDYGATAEELEAHFHGCGSVNRVTiLCDKFSGHPKGFAYIEFSDKESVRTS-LALDESLFRGRQIKV 116
Cdd:cd12392     1 EKNKLFVKGLPFSCTKEELEELFKQHGTVKDVR-LVTYRNGKPKGLAYVEYENEADASQAvLKTDGTEIKDHTISV 75

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1339869051  39 MEADARSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLA-LDESLFRGRQIKV 116
Cdd:cd12671     2 SDRSLRSVFVGNIPYEATEEQLKDIFSEVGPVVSFRLVYDRETGKPKGYGFCEYQDQETALSAMRnLNGYELNGRALRV 80

RNA recognition motif (RRM) found in RNA-binding protein 7 (RBM7) and similar proteins; This subfamily corresponds to the RRM of RBM7, RBM11 and their eukaryotic homologous. RBM7 is an ubiquitously expressed pre-mRNA splicing factor that enhances messenger RNA (mRNA) splicing in a cell-specific manner or in a certain developmental process, such as spermatogenesis. It interacts with splicing factors SAP145 (the spliceosomal splicing factor 3b subunit 2) and SRp20, and may play a more specific role in meiosis entry and progression. Together with additional testis-specific RNA-binding proteins, RBM7 may regulate the splicing of specific pre-mRNA species that are important in the meiotic cell cycle. RBM11 is a novel tissue-specific splicing regulator that is selectively expressed in brain, cerebellum and testis, and to a lower extent in kidney. It 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. Both, RBM7 and RBM11, contain 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 is responsible for RNA binding, whereas the C-terminal region permits nuclear localization and homodimerization.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1339869051  44 RSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKfSGHPKGFAYIEFSDKESVRTSLALDE--SLFrGRQIKV 116
Cdd:cd12336     2 RTLFVGNLDPRVTEEILYELFLQAGPLEGVKIPKDP-NGKPKNFAFVTFKHEVSVPYAIQLLNgiRLF-GREIRI 74

RNA recognition motif 1 (RRM1) found in Arabidopsis thaliana CTC-interacting domain protein CID8, CID9, CID10, CID11, CID12, CID 13 and similar proteins; This subgroup corresponds to the RRM1 domains found in A. thaliana CID8, CID9, CID10, CID11, CID12, CID 13 and mainly their plant homologs. These highly related RNA-binding proteins contain an N-terminal PAM2 domain (PABP-interacting motif 2), two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a basic region that resembles a bipartite nuclear localization signal. The biological role of this family remains unclear.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1339869051  44 RSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDkfSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKVIPKRT 121
Cdd:cd12459     3 RTVYVSDIDQQVTEEQLAALFSNCGQVVDCRICGD--PNSVLRFAFIEFTDEEGARAALSLSGTMLGFYPVRVLPSKT 78

RNA recognition motif 1 (RRM1) found in yeast protein gar2 and similar proteins; This subfamily corresponds to the RRM1 of yeast protein gar2, a novel nucleolar protein required for 18S rRNA and 40S ribosomal subunit accumulation. It shares similar domain architecture with nucleolin from vertebrates and NSR1 from Saccharomyces cerevisiae. The highly phosphorylated N-terminal domain of gar2 is made up of highly acidic regions separated from each other by basic sequences, and contains multiple phosphorylation sites. The central domain of gar2 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The C-terminal RGG (or GAR) domain of gar2 is rich in glycine, arginine and phenylalanine residues.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLA-LDESLFRGRQIKV 116
Cdd:cd12447     1 TLFVGGLSWNVDDPWLKKEFEKYGGVISARVITDRGSGRSKGYGYVDFATPEAAQKALAaMSGKEIDGRQINV 73

RNA recognition motif 2 (RRM2) found in yeast nucleolar protein 13 (Nop13p) and similar proteins; This subfamily corresponds to the RRM2 of Nop13p encoded by YNL175c from Saccharomyces cerevisiae. It shares high sequence similarity with nucleolar protein 12 (Nop12p). Both Nop12p and Nop13p are not essential for growth. However, unlike Nop12p that is localized to the nucleolus, Nop13p localizes primarily to the nucleolus but is also present in the nucleoplasm to a lesser extent. Nop13p contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL 102
Cdd:cd12397     1 LFVGNLSFETTEEDLRKHFAPAGKIRKVRMATFEDSGKCKGFAFVDFKEIESATNAV 57

RNA recognition motif (RRM) found in AZoospermia (DAZ) autosomal homologs, DAZL (DAZ-like) and BOULE; This subfamily corresponds to the RRM domain of two Deleted in AZoospermia (DAZ) autosomal homologs, DAZL (DAZ-like) and BOULE. BOULE is the founder member of the family and DAZL arose from BOULE in an ancestor of vertebrates. The DAZ gene subsequently originated from a duplication transposition of the DAZL gene. Invertebrates contain a single DAZ homolog, BOULE, while vertebrates, other than catarrhine primates, possess both BOULE and DAZL genes. The catarrhine primates possess BOULE, DAZL, and DAZ genes. The family members encode closely related RNA-binding proteins that are required for fertility in numerous organisms. These proteins contain an RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a varying number of copies of a DAZ motif, believed to mediate protein-protein interactions. DAZL and BOULE contain a single copy of the DAZ motif, while DAZ proteins can contain 8-24 copies of this repeat. Although their specific biochemical functions remain to be investigated, DAZL proteins may interact with poly(A)-binding proteins (PABPs), and act as translational activators of specific mRNAs during gametogenesis.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKfSGHPKGFAYIEFSDKESVRTSLALDESL-FRGRQIKVIP 118
Cdd:cd12412     5 IFVGGIDWDTTEEELREFFSKFGKVKDVKIIKDR-AGVSKGYGFVTFETQEDAEKIQKWGANLvFKGKKLNVGP 77

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLA-LDESLFRGRQIKV 116
Cdd:cd21609     2 LYVGNIPRNVTSEELAKIFEEAGTVEIAEVMYDRYTGRSRGFGFVTMGSVEDAKAAIEkLNGTEVGGREIKV 73

RNA recognition motif 3 (RRM3) found in yeast nucleolar protein 4 (Nop4p) and similar proteins; This subgroup corresponds to the RRM3 of Nop4p (also known as Nop77p), encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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                  ....*....|....*....|....*....|....*....|....*....|....
gi 1339869051  44 RSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKES 97
Cdd:cd12676     2 RTLFVRNLPFDATEDELYSHFSQFGPLKYARVVKDPATGRSKGTAFVKFKNKED 55

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESL-FRGRQIKV 116
Cdd:cd12284     1 LYVGSLHFNITEDMLRGIFEPFGKIEFVQLQKDPETGRSKGYGFIQFRDAEDAKKALEQLNGFeLAGRPMKV 72

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 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQI 114
Cdd:cd12325     1 LFVGGLSWETTEESLREYFSKYGEVVDCVVMKDPATGRSRGFGFVTFKDPSSVDAVLAARPHTLDGRTI 69

RNA recognition motif 1 (RRM1) found in La-related protein 7 (LARP7) and similar proteins; This subfamily corresponds to the RRM1 of LARP7, also termed La ribonucleoprotein domain family member 7, or P-TEFb-interaction protein for 7SK stability (PIP7S), an oligopyrimidine-binding protein that binds to the highly conserved 3'-terminal U-rich stretch (3' -UUU-OH) of 7SK RNA. LARP7 is a stable component of the 7SK small nuclear ribonucleoprotein (7SK snRNP). It intimately associates with all the nuclear 7SK and is required for 7SK stability. LARP7 also acts as a negative transcriptional regulator of cellular and viral polymerase II genes, acting by means of the 7SK snRNP system. It plays an essential role in the inhibition of positive transcription elongation factor b (P-TEFb)-dependent transcription, which has been linked to the global control of cell growth and tumorigenesis. LARP7 contains a La motif (LAM) and an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), at the N-terminal region, which mediates binding to the U-rich 3' terminus of 7SK RNA. LARP7 also carries another putative RRM domain at its C-terminus.

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                  ....*....|....*....|....*....|....*....|....*....|....
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVR 99
Cdd:cd12290     2 VYVELLPKNATHEWIEAVFSKYGEVVYVSIPRYKSTGDPKGFAFIEFETSESAQ 55

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 1339869051  44 RSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKfSGHPKGFAYIEFSDKESVRTSLA-LDESLFRGRQIKV 116
Cdd:cd12593     2 RTVFVGNLHSNVNEEILYELFLQAGPLTKVTIAKDK-EGKPKSFGFVCFKHAESVPYAIAlLNGIRLYGRPIKL 74

RNA recognition motif (RRM) found in SRA stem-loop-interacting RNA-binding protein (SLIRP) and similar proteins; This subfamily corresponds to the RRM of SLIRP, a widely expressed small steroid receptor RNA activator (SRA) binding protein, which binds to STR7, a functional substructure of SRA. SLIRP is localized predominantly to the mitochondria and plays a key role in modulating several nuclear receptor (NR) pathways. It functions as a co-repressor to repress SRA-mediated nuclear receptor coactivation. It modulates SHARP- and SKIP-mediated co-regulation of NR activity. SLIRP contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is required for SLIRP's corepression activities.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKV 116
Cdd:cd12242     2 LFVSNLPWTTGSSELKEYFSQFGKVKRCNLPFDKETGFHKGFGFVSFENEDGLRNALQKQKHIFEGNKVSV 72

RNA recognition motif (RRM) found in speckle targeted PIP5K1A-regulated poly(A) polymerase (Star-PAP) and similar proteins; This subfamily corresponds to the RRM of Star-PAP, also termed RNA-binding motif protein 21 (RBM21), which is a ubiquitously expressed U6 snRNA-specific terminal uridylyltransferase (U6-TUTase) essential for cell proliferation. Although it belongs to the well-characterized poly(A) polymerase protein superfamily, Star-PAP is highly divergent from both, the poly(A) polymerase (PAP) and the terminal uridylyl transferase (TUTase), identified within the editing complexes of trypanosomes. Star-PAP predominantly localizes at nuclear speckles and catalyzes RNA-modifying nucleotidyl transferase reactions. It functions in mRNA biosynthesis and may be regulated by phosphoinositides. It binds to glutathione S-transferase (GST)-PIPKIalpha. Star-PAP preferentially uses ATP as a nucleotide substrate and possesses PAP activity that is stimulated by PtdIns4,5P2. It contains an N-terminal C2H2-type zinc finger motif followed by an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a split PAP domain linked by a proline-rich region, a PAP catalytic and core domain, a PAP-associated domain, an RS repeat, and a nuclear localization signal (NLS).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1339869051  44 RSIYVGNVDYGATAEELEAHFHGCGSVNRVTIlcDKFSGHpkgFAYIEFSDKESVRTSLALDESLFRGRQIKVIPK 119
Cdd:cd12279     3 RSVFVSGFKRGTSELELSDYFQAFGPVASVVM--DKDKGV---YAIVEMDSTETVEKVLSQPQHCLNGQRLRVKPR 73

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 1339869051  35 IEEKMEADARSIYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKfSGHPKGFAYIEFSDKE 96
Cdd:TIGR01628 277 QERKMKAQGVNLYVKNLDDTVTDEKLRELFSECGEITSAKVMLDE-KGVSRGFGFVCFSNPE 337

RNA recognition motif 2 (RRM2) 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 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSLALDESLFRGRQIKV 116
Cdd:cd12330     2 IFVGGLAPDVTEEEFKEYFEQFGTVVDAVVMLDHDTGRSRGFGFVTFDSESAVEKVLSKGFHELGGKKVEV 72

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor SRSF2, SRSF8 and similar proteins; This subfamily corresponds to the RRM of SRSF2 and SRSF8. SRSF2, also termed protein PR264, or splicing component, 35 kDa (splicing factor SC35 or SC-35), is a prototypical SR protein that plays important roles in the alternative splicing of pre-mRNA. It is also involved in transcription elongation by directly or indirectly mediating the recruitment of elongation factors to the C-terminal domain of polymerase II. SRSF2 is exclusively localized in the nucleus and is restricted to nuclear processes. It contains a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by a C-terminal RS domain rich in serine-arginine dipeptides. The RRM is responsible for the specific recognition of 5'-SSNG-3' (S=C/G) RNA. In the regulation of alternative splicing events, it specifically binds to cis-regulatory elements on the pre-mRNA. The RS domain modulates SRSF2 activity through phosphorylation, directly contacts RNA, and promotes protein-protein interactions with the spliceosome. SRSF8, also termed SRP46 or SFRS2B, is a novel mammalian SR splicing factor encoded by a PR264/SC35 functional retropseudogene. SRSF8 is localized in the nucleus and does not display the same activity as PR264/SC35. It functions as an essential splicing factor in complementing a HeLa cell S100 extract deficient in SR proteins. Like SRSF2, SRSF8 contains a single N-terminal RRM and a C-terminal RS domain.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1339869051  48 VGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:cd12311     3 VDNLTYRTTPDDLRRVFEKYGEVGDVYIPRDRYTRESRGFAFVRFYDKRDAEDAIdAMDGAELDGRELRV 72

RNA recognition motif (RRM) found in the FET family of RNA-binding proteins; This subfamily corresponds to the RRM of FET (previously TET) (FUS/TLS, EWS, TAF15) family of RNA-binding proteins. This ubiquitously expressed family of similarly structured proteins predominantly localizing to the nuclear, includes FUS (also known as TLS or Pigpen or hnRNP P2), EWS (also known as EWSR1), TAF15 (also known as hTAFII68 or TAF2N or RPB56), and Drosophila Cabeza (also known as SARFH). The corresponding coding genes of these proteins are involved in deleterious genomic rearrangements with transcription factor genes in a variety of human sarcomas and acute leukemias. All FET proteins interact with each other and are therefore likely to be part of the very same protein complexes, which suggests a general bridging role for FET proteins coupling RNA transcription, processing, transport, and DNA repair. The FET proteins contain multiple copies of a degenerate hexapeptide repeat motif at the N-terminus. The C-terminal region consists of a conserved nuclear import and retention signal (C-NLS), a putative zinc-finger domain, and a conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is flanked by 3 arginine-glycine-glycine (RGG) boxes. FUS and EWS might have similar sequence specificity; both bind preferentially to GGUG-containing RNAs. FUS has also been shown to bind strongly to human telomeric RNA and to small low-copy-number RNAs tethered to the promoter of cyclin D1. To date, nothing is known about the RNA binding specificity of TAF15.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNR--------VTILCDKFSGHPKGFAYIEFSDKESVRTSLA-LDESLFRGRQIKV 116
Cdd:cd12280     1 IFVSGLPPDVTIDELADLFGQIGIIKRykdtwppkIKIYTDKETGKPKGEATLTYEDPSAAKAAIEwFNGKEFRGNKIKV 80

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor 3 (SRSF3) and similar proteins; This subfamily corresponds to the RRM of two serine/arginine (SR) proteins, serine/arginine-rich splicing factor 3 (SRSF3) and serine/arginine-rich splicing factor 7 (SRSF7). SRSF3, also termed pre-mRNA-splicing factor SRp20, modulates alternative splicing by interacting with RNA cis-elements in a concentration- and cell differentiation-dependent manner. It is also involved in termination of transcription, alternative RNA polyadenylation, RNA export, and protein translation. SRSF3 is critical for cell proliferation, and tumor induction and maintenance. It can shuttle between the nucleus and cytoplasm. SRSF7, also termed splicing factor 9G8, plays a crucial role in both constitutive splicing and alternative splicing of many pre-mRNAs. Its localization and functions are tightly regulated by phosphorylation. SRSF7 is predominantly present in the nuclear and can shuttle between nucleus and cytoplasm. It cooperates with the export protein, Tap/NXF1, helps mRNA export to the cytoplasm, and enhances the expression of unspliced mRNA. Moreover, SRSF7 inhibits tau E10 inclusion through directly interacting with the proximal downstream intron of E10, a clustering region for frontotemporal dementia with Parkinsonism (FTDP) mutations. Both SRSF3 and SRSF7 contain a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal RS domain rich in serine-arginine dipeptides. The RRM domain is involved in RNA binding, and the RS domain has been implicated in protein shuttling and protein-protein interactions.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTIlcdkfSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:cd12373     2 VYVGNLGPRVTKRELEDAFEKYGPLRNVWV-----ARNPPGFAFVEFEDPRDAEDAVrALDGRRICGSRVRV 68

RNA recognition motif (RRM) found in cyclophilin-33 (Cyp33) and similar proteins; This subfamily corresponds to the RRM of Cyp33, also termed peptidyl-prolyl cis-trans isomerase E (PPIase E), or cyclophilin E, or rotamase E. Cyp33 is a nuclear RNA-binding cyclophilin with an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal PPIase domain. Cyp33 possesses RNA-binding activity and preferentially binds to polyribonucleotide polyA and polyU, but hardly to polyG and polyC. It binds specifically to mRNA, which can stimulate its PPIase activity. Moreover, Cyp33 interacts with the third plant homeodomain (PHD3) zinc finger cassette of the mixed lineage leukemia (MLL) proto-oncoprotein and a poly-A RNA sequence through its RRM domain. It further mediates downregulation of the expression of MLL target genes HOXC8, HOXA9, CDKN1B, and C-MYC, in a proline isomerase-dependent manner. Cyp33 also possesses a PPIase activity that catalyzes cis-trans isomerization of the peptide bond preceding a proline, which has been implicated in the stimulation of folding and conformational changes in folded and unfolded proteins. The PPIase activity can be inhibited by the immunosuppressive drug cyclosporin A.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1339869051  46 IYVGNVDYGATAEELEAHFHGCGSVNRVTILCDKFSGHPKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:cd12347     1 LYVGGLAEEVDEKVLHAAFIPFGDIVDIQIPLDYETEKHRGFAFVEFEEAEDAAAAIdNMNESELFGRTIRV 72

RNA recognition motif 1 (RRM1) found in yeast regulator of rDNA transcription protein 5 (RRT5) and similar proteins; This subfamily corresponds to the RRM1 of the lineage specific family containing a group of uncharacterized yeast regulators of rDNA transcription protein 5 (RRT5), which may play roles in the modulation of rDNA transcription. RRT5 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1339869051  45 SIYVGNVDYGATAEELEAHFHGCGSVNrVTILCD-----KFSGH-PKGFAYIEFSDKESVRTSL-ALDESLFRGRQIKV 116
Cdd:cd12409     1 RVYISNLSYSTTEEELEELLKDYKPVS-VLIPSYtvrgfRSRKHrPLGIAYAEFSSVEEAEKVVkDLNGKVFKGRKLFV 78