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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEI 181
Cdd:cd12680   1 TKLLVSNLDFGVSDADIKELFAEFGTLKKAAVHYDRSGRSLGTAEVVFERRADALKAMKQYNGVPLDGRPMKIQL 75

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEI 181
Cdd:cd12680   1 TKLLVSNLDFGVSDADIKELFAEFGTLKKAAVHYDRSGRSLGTAEVVFERRADALKAMKQYNGVPLDGRPMKIQL 75

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 18408471   109 VYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMK 178
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGRELK 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18408471    74 KLARRKRSLPWQNQNDLYEETLRAVGVSgvevgttVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVV 153
Cdd:TIGR01628 260 KRAEREAELRRKFEELQQERKMKAQGVN-------LYVKNLDDTVTDEKLRELFSECGEITSAKVMLDEKGVSRGFGFVC 332

                          90       100
                  ....*....|....*....|....
gi 18408471   154 YMRRSDAIQAMRKYNNVLLDGRPM 177
Cdd:TIGR01628 333 FSNPEEANRAVTEMHGRMLGGKPL 356

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEI 181
Cdd:cd12680   1 TKLLVSNLDFGVSDADIKELFAEFGTLKKAAVHYDRSGRSLGTAEVVFERRADALKAMKQYNGVPLDGRPMKIQL 75

RNA recognition motif (RRM) found in S6K1 Aly/REF-like target (SKAR) and similar proteins; This subgroup corresponds to the RRM of SKAR, also termed polymerase delta-interacting protein 3 (PDIP3), 46 kDa DNA polymerase delta interaction protein (PDIP46), belonging to the Aly/REF family of RNA binding proteins that have been implicated in coupling transcription with pre-mRNA splicing and nucleo-cytoplasmic mRNA transport. SKAR is widely expressed and localizes to the nucleus. It may be a critical player in the function of S6K1 in cell and organism growth control by binding the activated, hyperphosphorylated form of S6K1 but not S6K2. Furthermore, SKAR functions as a protein partner of the p50 subunit of DNA polymerase delta. In addition, SKAR may have particular importance in pancreatic beta cell size determination and insulin secretion. SKAR contains a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHydkngRPsGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12681   1 TRLTVSNLHPSVTEDDIVELFSVIGALKRARLV-----RP-GVAEVVYVRREDAITAIKKYNNRELDGQPMKC 67

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471    108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKN-GRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVESVRLVRDKEtGKSKGFAFVEFESEEDAEKALEALNGKELDGRPLKV 73

RNA recognition motif (RRM) found in yeast RNA annealing protein YRA1 (Yra1p), yeast mRNA export protein mlo3 and similar proteins; This subfamily corresponds to the RRM of Yra1p and mlo3. Yra1p is an essential nuclear RNA-binding protein encoded by Saccharomyces cerevisiae YRA1 gene. It belongs to the evolutionarily conserved REF (RNA and export factor binding proteins) family of hnRNP-like proteins. Yra1p possesses potent RNA annealing activity and interacts with a number of proteins involved in nuclear transport and RNA processing. It binds to the mRNA export factor Mex67p/TAP and couples transcription to export in yeast. Yra1p is associated with Pse1p and Kap123p, two members of the beta-importin family, further mediating transport of Yra1p into the nucleus. In addition, the co-transcriptional loading of Yra1p is required for autoregulation. Yra1p consists of two highly conserved N- and C-terminal boxes and a central RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). This subfamily includes RNA-annealing protein mlo3, also termed mRNA export protein mlo3, which has been identified in fission yeast as a protein that causes defects in chromosome segregation when overexpressed. It shows high sequence similarity with Yra1p.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 18408471 107 TTVYITNLDQGVTNEDIRELYA-EIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDG-RPMKLEIL 182
Cdd:cd12267   1 SKVIVSNLPKDVTEAQIREYFVsQIGPIKRVLLSYNEGGKSTGIANITFKRAGDATKAYDKFNGRLDDGnRKMKVEVV 78

RNA recognition motif (RRM) found in SR-related and CTD-associated factor 4 (SCAF4), SR-related and CTD-associated factor 8 (SCAF8) and similar proteins; This subfamily corresponds to the RRM in a new class of SCAFs (SR-like CTD-associated factors), including SCAF4, SCAF8 and similar proteins. The biological role of SCAF4 remains unclear, but it shows high sequence similarity to SCAF8 (also termed CDC5L complex-associated protein 7, or RNA-binding motif protein 16, or CTD-binding SR-like protein RA8). SCAF8 is a nuclear matrix protein that interacts specifically with a highly serine-phosphorylated form of the carboxy-terminal domain (CTD) of the largest subunit of RNA polymerase II (pol II). The pol II CTD plays a role in coupling transcription and pre-mRNA processing. In addition, SCAF8 co-localizes primarily with transcription sites that are enriched in nuclear matrix fraction, which is known to contain proteins involved in pre-mRNA processing. Thus, SCAF8 may play a direct role in coupling with both, transcription and pre-mRNA processing, processes. SCAF8 and SCAF4 both contain a conserved N-terminal CTD-interacting domain (CID), an atypical RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNPs (ribonucleoprotein domain), and serine/arginine-rich motifs.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRY-AIHydkngrPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12227   3 TTLWVGHLSKKVTQEELKNLFEEYGEIQSIdMIP------PRGCAYVCMKTRQDAHRALQKLKNHKLRGKSIKI 70

RNA recognition motif (RRM) found in Zinc finger CCHC-type and RNA-binding motif-containing protein 1 (ZCRB1) and similar proteins; This subfamily corresponds to the RRM of ZCRB1, also termed MADP-1, or U11/U12 small nuclear ribonucleoprotein 31 kDa protein (U11/U12 snRNP 31 or U11/U12-31K), a novel multi-functional nuclear factor, which may be involved in morphine dependence, cold/heat stress, and hepatocarcinoma. It is located in the nucleoplasm, but outside the nucleolus. ZCRB1 is one of the components of U11/U12 snRNPs that bind to U12-type pre-mRNAs and form a di-snRNP complex, simultaneously recognizing the 5' splice site and branchpoint sequence. ZCRB1 is characterized by an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a CCHC-type Zinc finger motif. In addition, it contains core nucleocapsid motifs, and Lys- and Glu-rich domains.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPS-GSAEVVYMRRSDAIQAMRKYNNVLLDGRPMK 178
Cdd:cd12393   2 STVYVSNLPFSLTNNDLHQIFSKYGKVVKVTILKDKETRKSkGVAFVLFLDRESAHNAVRAMNNKELFGRTLK 74

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHY----DKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12223   2 TNLYVGNLPPSVTEEVLLREFGRFGPLASVKIMWprteEERRRNRNCGFVAFMSRADAERAMRELNGKDVMGYELKL 78

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 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLE 180
Cdd:cd12336   3 TLFVGNLDPRVTEEILYELFLQAGPLEGVKIPKDPNGKPKNFAFVTFKHEVSVPYAIQLLNGIRLFGREIRIK 75

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18408471 109 VYITNLDQGVTNEDIRELYAEIGELKRYA--------IHYDKN-GRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12280   1 IFVSGLPPDVTIDELADLFGQIGIIKRYKdtwppkikIYTDKEtGKPKGEATLTYEDPSAAKAAIEWFNGKEFRGNKIKV 80

                ..
gi 18408471 180 EI 181
Cdd:cd12280  81 SL 82

RNA recognition motif 3 (RRM3) 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 third RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd21607   4 TIYCSNLPLSTAESDLYDLFETIGKVNNAELKYDETGDPTGSAVVEYENLDDADVCISKLNNYNYGGCDLKI 75

RNA recognition motif 2 (RRM2) found in vertebrate heterogeneous nuclear ribonucleoprotein M (hnRNP M); This subgroup corresponds to the RRM2 of hnRNP M, a pre-mRNA binding protein that may play an important role in the pre-mRNA processing. It also preferentially binds to poly(G) and poly(U) RNA homopolymers. hnRNP M is able to interact with early spliceosomes, further influencing splicing patterns of specific pre-mRNAs. It functions as the receptor of carcinoembryonic antigen (CEA) that contains the penta-peptide sequence PELPK signaling motif. In addition, hnRNP M and another splicing factor Nova-1 work together as dopamine D2 receptor (D2R) pre-mRNA-binding proteins. They regulate alternative splicing of D2R pre-mRNA in an antagonistic manner. hnRNP M contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an unusual hexapeptide-repeat region rich in methionine and arginine residues (MR repeat motif).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEI 181
Cdd:cd12659   1 STVFVANLDYKVGWKKLKEVFSMAGVVVRADILEDKDGKSRGIGTVTFEQPIEAVQAISMFNGQLLFDRPMHVKM 75

RNA recognition motif 2 (RRM2) found in Drosophila sex-lethal (SXL) and similar proteins; This subfamily corresponds to the RRM2 of the sex-lethal protein (SXL) which governs sexual differentiation and X chromosome dosage compensation in Drosophila melanogaster. It induces female-specific alternative splicing of the transformer (tra) pre-mRNA by binding to the tra uridine-rich polypyrimidine tract at the non-sex-specific 3' splice site during the sex-determination process. SXL binds also to its own pre-mRNA and promotes female-specific alternative splicing. SXL contains an N-terminal Gly/Asn-rich domain that may be responsible for the protein-protein interaction, and tandem RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), that show high preference to bind single-stranded, uridine-rich target RNA transcripts.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 18408471 106 GTTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDK-NGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEI 181
Cdd:cd12651   2 DTNLYVTNLPRTITEDELDTIFGAYGNIVQKNLLRDKlTGRPRGVAFVRYDKREEAQAAISALNGTIPEGGTQPLSV 78

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKyNNVLLDGRPM 177
Cdd:cd12391   1 TVFVSNLDYSVPEDKIREIFSGCGEITDVRLVKNYKGKSKGYCYVEFKDEESAQKALKL-DRQPVEGRPM 69

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 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKN-GRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMK 178
Cdd:cd12398   2 SVFVGNIPYDATEEQLKEIFSEVGPVVSFRLVTDREtGKPKGYGFCEFRDAETALSAVRNLNGYELNGRPLR 73

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 18408471 104 EVGTTVYITNLDQGVTNEDIRELYAEIGELKrYAIHYDKNGRPSGSAEVVYMRRSDAIQAMrKYNNVLLDGRPMKLE 180
Cdd:cd12260   2 EIRRTVYVGNLDPSTTADQLLEFFSQAGEVK-YVRMAGDETQPTRYAFVEFAEQTSVINAL-KLNGKMFGGRPLKVN 76

RNA recognition motif 2 (RRM2) found in heterogeneous nuclear ribonucleoprotein M (hnRNP M) and similar proteins; This subfamily corresponds to the RRM2 of heterogeneous nuclear ribonucleoprotein M (hnRNP M), myelin expression factor 2 (MEF-2 or MyEF-2 or MST156) and similar proteins. hnRNP M is pre-mRNA binding protein that may play an important role in the pre-mRNA processing. It also preferentially binds to poly(G) and poly(U) RNA homopolymers. hnRNP M is able to interact with early spliceosomes, further influencing splicing patterns of specific pre-mRNAs. It functions as the receptor of carcinoembryonic antigen (CEA) that contains the penta-peptide sequence PELPK signaling motif. In addition, hnRNP M and another splicing factor Nova-1 work together as dopamine D2 receptor (D2R) pre-mRNA-binding proteins. They regulate alternative splicing of D2R pre-mRNA in an antagonistic manner. hnRNP M contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an unusual hexapeptide-repeat region rich in methionine and arginine residues (MR repeat motif). MEF-2 is 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 shows high sequence homology with hnRNP M. It also contains three RRMs, which may be responsible for its ssDNA binding activity.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 18408471 109 VYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPM 177
Cdd:cd12386   1 IFVANLDYKVGWKKLKEVFKLAGKVVRADIREDKDGKSRGMGVVQFEHPIEAVQAISMFNGQMLFDRPM 69

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSgSAEVVYMRRSDAIQ-AMRKYNNVLLDGRPMKLE 180
Cdd:cd12593   3 TVFVGNLHSNVNEEILYELFLQAGPLTKVTIAKDKEGKPK-SFGFVCFKHAESVPyAIALLNGIRLYGRPIKLQ 75

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKnGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGR 175
Cdd:cd21605   3 SIFVGNLPFDCTWEDLKDHFSQVGEVIRADIVTSR-GRHRGMGTVEFTNKEDVDRAISKFDHTMFMGR 69

RNA recognition motif in type II polyadenylate-binding proteins; This subfamily corresponds to the RRM of type II polyadenylate-binding proteins (PABPs), including polyadenylate-binding protein 2 (PABP-2 or PABPN1), embryonic polyadenylate-binding protein 2 (ePABP-2 or PABPN1L) and similar proteins. PABPs are 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. ePABP-2 is predominantly located in the cytoplasm and PABP-2 is located in the nucleus. In contrast to the type I PABPs containing four copies of RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), the type II PABPs contains a single highly-conserved RRM. This subfamily also includes Saccharomyces cerevisiae RBP29 (SGN1, YIR001C) gene encoding cytoplasmic mRNA-binding protein Rbp29 that binds preferentially to poly(A). Although not essential for cell viability, Rbp29 plays a role in modulating the expression of cytoplasmic mRNA. Like other type II PABPs, Rbp29 contains one RRM only.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 18408471 109 VYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKN-GRPSGSAEVVYMRRSDAIQAMrKYNNVLLDGRPMK 178
Cdd:cd12306   2 IYVGNVDYGTTPEELQAHFKSCGTINRVTILCDKFtGQPKGFAYIEFVDKSSVENAL-LLNESEFRGRQIK 71

sex-lethal family splicing factor; This model describes the sex-lethal family of splicing factors found in Dipteran insects. The sex-lethal phenotype, however, may be limited to the Melanogasters and closely related species. In Drosophila the protein acts as an inhibitor of splicing. This subfamily is most closely related to the ELAV/HUD subfamily of splicing factors (TIGR01661).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 18408471   107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDK-NGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEI 181
Cdd:TIGR01659 194 TNLYVTNLPRTITDDQLDTIFGKYGQIVQKNILRDKlTGTPRGVAFVRFNKREEAQEAISALNNVIPEGGSQPLTV 269

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 18408471 110 YITNLDQGVTNEDIRELYAEIGELKRYAIHYD-KNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12284   2 YVGSLHFNITEDMLRGIFEPFGKIEFVQLQKDpETGRSKGYGFIQFRDAEDAKKALEQLNGFELAGRPMKV 72

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGElkryaIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12346   2 TTVFVGGLDPNVTEEDLRVLFGPFGE-----IVYVKIPPGKGCGFVQFVNRASAEAAIQKLQGTPIGGSRIRL 69

RNA recognition motif (RRM) found in Helicobacter pylori HP0827 protein and similar proteins; This subfamily corresponds to the RRM of H. pylori HP0827, a putative ssDNA-binding protein 12rnp2 precursor, containing one RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The ssDNA binding may be important in activation of HP0827.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 18408471 109 VYITNLDQGVTNEDIRELYAEIGELKRYAIHYDK-NGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12399   1 LYVGNLPYSASEEQLKSLFGQFGAVFDVKLPMDReTKRPRGFGFVELQEEESAEKAIAKLDGTDFMGRTIRV 72

RNA recognition motif 1 (RRM1) found in Schizosaccharomyces pombe mRNA export factor Crp79 and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the first RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471 106 GTTVYITNLDQGVTNEDIREL---YAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGR 175
Cdd:cd21619   1 SNTIYVGNIDMTINEDALEKIfsrYGQVESVRRPPIHTDKADRTTGFGFIKYTDAESAERAMQQADGILLGRR 73

RNA recognition motif (RRM) found in Drosophila melanogaster RNA-binding protein cabeza and similar proteins; This subgroup corresponds to the RRM in cabeza, also termed P19, or sarcoma-associated RNA-binding fly homolog (SARFH). It is a putative homolog of human RNA-binding proteins FUS (also termed TLS or Pigpen or hnRNP P2), EWS (also termed EWSR1), TAF15 (also termed hTAFII68 or TAF2N or RPB56), and belongs to the of the FET (previously TET) (FUS/TLS, EWS, TAF15) family of RNA- and DNA-binding proteins whose expression is altered in cancer. It is a nuclear RNA binding protein that may play an important role in the regulation of RNA metabolism during fly development. Cabeza contains one RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18408471 109 VYITNLDQGVTNEDIRELYAEIGELKRYA--------IHYDK-NGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12534   1 VFVSNLPPNTTEQDLAEHFGSIGIIKIDKktgkpkiwLYKDKdTGEPKGEATVTYDDPHAASAAIEWFNNKDFMGNTIKV 80

                ..
gi 18408471 180 EI 181
Cdd:cd12534  81 SL 82

RNA recognition motif 2 (RRM2) found in granule-associated RNA binding proteins (p40-TIA-1 and TIAR), and yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1; This subfamily corresponds to the RRM3 of TIA-1, TIAR, and PUB1. Nucleolysin TIA-1 isoform p40 (p40-TIA-1 or TIA-1) and nucleolysin TIA-1-related protein (TIAR) are granule-associated RNA binding proteins involved in inducing apoptosis in cytotoxic lymphocyte (CTL) target cells. They share high sequence similarity and 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. This subfamily also includes a yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1, termed ARS consensus-binding protein ACBP-60, or poly uridylate-binding protein, or poly(U)-binding protein, which has been identified as both a heterogeneous nuclear RNA-binding protein (hnRNP) and a cytoplasmic mRNA-binding protein (mRNP). It may be stably bound to a translationally inactive subpopulation of mRNAs within the cytoplasm. PUB1 is distributed in both, the nucleus and the cytoplasm, and binds to poly(A)+ RNA (mRNA or pre-mRNA). Although it is one of the major cellular proteins cross-linked by UV light to polyadenylated RNAs in vivo, PUB1 is nonessential for cell growth in yeast. PUB1 also binds to T-rich single stranded DNA (ssDNA); however, there is no strong evidence implicating PUB1 in the mechanism of DNA replication. PUB1 contains three RRMs, and a GAR motif (glycine and arginine rich stretch) that is located between RRM2 and RRM3.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 18408471 107 TTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKngrpsGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMK 178
Cdd:cd12354   1 TTVYVGNITKGLTEALLQQTFSPFGQILEVRVFPDK-----GYAFIRFDSHEAATHAIVSVNGTIINGQAVK 67

RNA recognition motif 1 (RRM1) found in granule-associated RNA binding proteins p40-TIA-1 and TIAR; This subfamily corresponds to the RRM1 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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18408471 110 YITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGR-PSGSAEvvYMRRSDAIQAMRKYNNVLLDGRPMK 178
Cdd:cd12352   2 YVGNLDRQVTEDLILQLFSQIGPCKSCKMITEHGGNdPYCFVE--FYEHNHAAAALQAMNGRKILGKEVK 69

RNA recognition motif 2 (RRM2) found in RNA-binding protein 40 (RBM40) and similar proteins; This subfamily corresponds to the RRM2 of RBM40 and the RRM of RBM41. RBM40, also known as RNA-binding region-containing protein 3 (RNPC3) or U11/U12 small nuclear ribonucleoprotein 65 kDa protein (U11/U12-65K protein). It serves as a bridging factor between the U11 and U12 snRNPs. It contains two RNA recognition motifs (RRMs), also known as RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), connected by a linker that includes a proline-rich region. It binds to the U11-associated 59K protein via its RRM1 and employs the RRM2 to bind hairpin III of the U12 small nuclear RNA (snRNA). The proline-rich region might be involved in protein-protein interactions. RBM41 contains only one RRM. Its biological function remains unclear.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 18408471 108 TVYITNLDQGVTNEDIRELYA-----EIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPM 177
Cdd:cd12239   3 RLYVKNLSKRVSEKDLKYIFGrfvdsSSEEKNMFDIRLMTEGRMKGQAFITFPSEELAEKALNLTNGYVLHGKPM 77

ELAV/HuD family splicing factor; This model describes the ELAV/HuD subfamily of splicing factors found in metazoa. HuD stands for the human paraneoplastic encephalomyelitis antigen D of which there are 4 variants in human. ELAV stnds for the Drosophila Embryonic lethal abnormal visual protein. ELAV-like splicing factors are also known in human as HuB (ELAV-like protein 2), HuC (ELAV-like protein 3, Paraneoplastic cerebellar degeneration-associated antigen) and HuR (ELAV-like protein 1). These genes are most closely related to the sex-lethal subfamily of splicing factors found in Dipteran insects (TIGR01659). These proteins contain 3 RNA-recognition motifs (rrm: pfam00076).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18408471   104 EVGTTVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDK-NGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLEIL 182
Cdd:TIGR01661   1 ESKTNLIVNYLPQTMTQEEIRSLFTSIGEIESCKLVRDKvTGQSLGYGFVNYVRPEDAEKAVNSLNGLRLQNKTIKVSYA 80

                          90       100
                  ....*....|....*....|....*
gi 18408471   183 GGNTESAPvAARVNVTGLNGRMKRS 207
Cdd:TIGR01661  81 RPSSDSIK-GANLYVSGLPKTMTQH 104

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELkryaIHYDKNGRPSGS--AEVVYMRRSDAIQAMRKYNNVLLDGRPMKL 179
Cdd:cd12350   4 TLFIGNLEKTTTYGDLRNIFERFGEI----IDIDIKKQNGNPqyAFLQYCDIASVVKAIKKMDGEYLGNNRLKL 73

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 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDK-NGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRP 176
Cdd:cd21608   1 KLYVGNLSWDTTEDDLRDLFSEFGEVESAKVITDReTGRSRGFGFVTFSTAEAAEAAIDALNGKELDGRS 70

RNA recognition motif (RRM) found in transformer-2 protein homolog alpha (TRA-2 alpha) and similar proteins; This subgroup corresponds to the RRM of TRA2-alpha or TRA-2-alpha, also termed transformer-2 protein homolog A, a mammalian homolog of Drosophila transformer-2 (Tra2). TRA2-alpha is a 40-kDa serine/arginine-rich (SR) protein (SRp40) that specifically binds to gonadotropin-releasing hormone (GnRH) exonic splicing enhancer on exon 4 (ESE4) and is necessary for enhanced GnRH pre-mRNA splicing. It strongly stimulates GnRH intron A excision in a dose-dependent manner. In addition, TRA2-alpha can interact with either 9G8 or SRp30c, which may also be crucial for ESE-dependent GnRH pre-mRNA splicing. TRA2-alpha contains a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), flanked by the N- and C-terminal arginine/serine (RS)-rich regions.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471 119 TNEDIRELYAEIGELKRYAIHYD-KNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLE 180
Cdd:cd12642  17 TERDLREVFSRYGPLAGVNVVYDqRTGRSRGFAFVYFERIDDSKEAMERANGMELDGRRIRVD 79

RNA recognition motif 2 (RRM2) found in the p54nrb/PSF/PSP1 family; This subfamily corresponds to the RRM2 of the p54nrb/PSF/PSP1 family, including 54 kDa nuclear RNA- and DNA-binding protein (p54nrb or NonO or NMT55), polypyrimidine tract-binding protein (PTB)-associated-splicing factor (PSF or POMp100), paraspeckle protein 1 (PSP1 or PSPC1), which are ubiquitously expressed and are conserved in vertebrates. p54nrb is a multi-functional protein involved in numerous nuclear processes including transcriptional regulation, splicing, DNA unwinding, nuclear retention of hyperedited double-stranded RNA, viral RNA processing, control of cell proliferation, and circadian rhythm maintenance. PSF is also a multi-functional protein that binds RNA, single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and many factors, and mediates diverse activities in the cell. PSP1 is a novel nucleolar factor that accumulates within a new nucleoplasmic compartment, termed paraspeckles, and diffusely distributes in the nucleoplasm. The cellular function of PSP1 remains unknown currently. The family also includes some p54nrb/PSF/PSP1 homologs from invertebrate species, such as the Drosophila melanogaster gene no-ontransient A (nonA) encoding puff-specific protein Bj6 (also termed NONA) and Chironomus tentans hrp65 gene encoding protein Hrp65. D. melanogaster NONA is involved in eye development and behavior and may play a role in circadian rhythm maintenance, similar to vertebrate p54nrb. C. tentans Hrp65 is a component of nuclear fibers associated with ribonucleoprotein particles in transit from the gene to the nuclear pore. All family members contains a DBHS domain (for Drosophila behavior, human splicing), which comprises two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a charged protein-protein interaction module. PSF has an additional large N-terminal domain that differentiates it from other family members.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYDKNGRPSGSAEVVYMRRSDAIQAMRKYN 168
Cdd:cd12333   1 ALRVKNLSPYVSNELLEQAFSQFGDVERAVVIVDDRGRSTGEGIVEFSRKPGAQAALKRCS 61

RNA recognition motif (RRM) found in U1 small nuclear ribonucleoprotein 70 kDa (U1-70K) and similar proteins; This subfamily corresponds to the RRM of U1-70K, also termed snRNP70, a key component of the U1 snRNP complex, which is one of the key factors facilitating the splicing of pre-mRNA via interaction at the 5' splice site, and is involved in regulation of polyadenylation of some viral and cellular genes, enhancing or inhibiting efficient poly(A) site usage. U1-70K plays an essential role in targeting the U1 snRNP to the 5' splice site through protein-protein interactions with regulatory RNA-binding splicing factors, such as the RS protein ASF/SF2. Moreover, U1-70K protein can specifically bind to stem-loop I of the U1 small nuclear RNA (U1 snRNA) contained in the U1 snRNP complex. It also mediates the binding of U1C, another U1-specific protein, to the U1 snRNP complex. U1-70K contains a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by an adjacent glycine-rich region at the N-terminal half, and two serine/arginine-rich (SR) domains at the C-terminal half. The RRM is responsible for the binding of stem-loop I of U1 snRNA molecule. Additionally, the most prominent immunodominant region that can be recognized by auto-antibodies from autoimmune patients may be located within the RRM. The SR domains are involved in protein-protein interaction with SR proteins that mediate 5' splice site recognition. For instance, the first SR domain is necessary and sufficient for ASF/SF2 Binding. The family also includes Drosophila U1-70K that is an essential splicing factor required for viability in flies, but its SR domain is dispensable. The yeast U1-70k doesn't contain easily recognizable SR domains and shows low sequence similarity in the RRM region with other U1-70k proteins and therefore not included in this family. The RRM domain is dispensable for yeast U1-70K function.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYAIHYD-KNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGR 175
Cdd:cd12236   3 TLFVARLSYDTTESKLRREFEKYGPIKRVRLVRDkKTGKSRGYAFIEFEHERDMKAAYKHADGKKIDGR 71

RNA recognition motif 3 (RRM3) found in vertebrate nucleolin; This subfamily corresponds to the RRM3 of ubiquitously expressed protein nucleolin, also termed protein C23, is 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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 18408471 108 TVYITNLDQGVTNEDIRELYAEIGELKRYaihyDKNGRPSGSAEVVYMRRSDAIQAMRKYNNVLLDGRPMKLE 180
Cdd:cd12405   3 TLVVNNLSYSATEESLQSVFEKATSIRIP----QNNGRPKGYAFVEFESVEDAKEALESCNNTEIEGRSIRLE 71