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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034575770  78 TKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQ 144
Cdd:cd12607     1 TKLHVGNISSSCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAMEAIRGLDNTEFQGKRMHVQ 67

zinc finger;

                           10
                   ....*....|....*.
gi 1034575770  161 GCYRCGKEGHWSKECP 176
Cdd:smart00343   1 KCYNCGKEGHIARDCP 16

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034575770  78 TKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQ 144
Cdd:cd12607     1 TKLHVGNISSSCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAMEAIRGLDNTEFQGKRMHVQ 67

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770   1 MVKLFIGNLPREATEQEIRSLFEQYGKVLECDIIKN--------YGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEASKN 72
Cdd:COG0724     1 SMKIYVGNLPYSVTEEDLRELFSEYGEVTSVKLITDretgrsrgFGFVEMPDDEEAQAAIEALNGAELMGRTLKVNEARP 80

                  ...
gi 1034575770  73 KSK 75
Cdd:COG0724    81 REE 83

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034575770   79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHV 143
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVESVRLVRDketgkskgFAFVEFESEEDAEKALEALNGKELDGRPLKV 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770   4 LFIGNLPREATEQEIRSLFEQYGKVLECDII-------KNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEASKNKS-- 74
Cdd:TIGR01628  91 IFVKNLDKSVDNKALFDTFSKFGNILSCKVAtdengksRGYGFVHFEKEESAKAAIQKVNGMLLNDKEVYVGRFIKKHer 170

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770  75 -----KASTKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAEDAVEAIRGLDNTEF----QG 138
Cdd:TIGR01628 171 eaaplKKFTNLYVKNLDPSVNEDKLRELFAKFGEITSAAVMKDgsgrsrgFAFVNFEKHEDAAKAVEEMNGKKIglakEG 250

                         170
                  ....*....|.
gi 1034575770 139 KRMHVQLSTSR 149
Cdd:TIGR01628 251 KKLYVGRAQKR 261

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034575770  82 VGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAEDAVEAIRGLDNTEFQGKRMH 142
Cdd:pfam00076   3 VGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDetgrskgFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKN--------YGFVHIEDKTAAEDAIRNLHHYKLHGVNINVE-ASKNK 73
Cdd:TIGR01642 297 RIYIGNLPLYLGEDQIKELLESFGDLKAFNLIKDiatglskgYAFCEYKDPSVTDVAIAALNGKDTGDNKLHVQrACVGA 376

                  ...
gi 1034575770  74 SKA 76
Cdd:TIGR01642 377 NQA 379

universal minicircle sequence binding protein (UMSBP); Provisional

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1034575770 138 GKRMHVQLSTSRLRTAPGMGDQSgCYRCGKEGHWSKECPVDRTGR 182
Cdd:PTZ00368    7 GGVGHQSRECPNSAPAGAAKARP-CYKCGEPGHLSRECPSAPGGR 50

universal minicircle sequence binding protein (UMSBP); Provisional

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034575770 145 LSTSRLRTAPGMGDQSgCYRCGKEGHWSKECPVDRTG 181
Cdd:PTZ00368   39 LSRECPSAPGGRGERS-CYNCGKTGHLSRECPEAPPG 74

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034575770  78 TKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQ 144
Cdd:cd12607     1 TKLHVGNISSSCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAMEAIRGLDNTEFQGKRMHVQ 67

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVE 68
Cdd:cd12343     1 KIFVGNLPDAATSEELRALFEKYGKVTECDIVKNYAFVHMEKEEDAEDAIKALNGYEFMGSRINVE 66

RNA recognition motif 2 (RRM2) found in vertebrate RRM-containing coactivator activator/modulator (CoAA); This subgroup corresponds to the RRM2 of CoAA, also termed RNA-binding protein 14 (RBM14), or paraspeckle protein 2 (PSP2), or synaptotagmin-interacting protein (SYT-interacting protein), a heterogeneous nuclear ribonucleoprotein (hnRNP)-like protein identified as a nuclear receptor coactivator. It mediates transcriptional coactivation and RNA splicing effects in a promoter-preferential manner and is enhanced by thyroid hormone receptor-binding protein (TRBP). CoAA contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a TRBP-interacting domain. It stimulates transcription through its interactions with coactivators, such as TRBP and CREB-binding protein CBP/p300, via the TRBP-interacting domain and interaction with an RNA-containing complex, such as DNA-dependent protein kinase-poly(ADP-ribose) polymerase complexes, via the RRMs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQL 145
Cdd:cd12609     2 KIFVGNVSATCTSDELRGLFEEFGRVVECDKVKDYAFVHMEREEEALAAIEALNGKEVKGRRINVEL 68

RNA recognition motif 1 (RRM1) found in vertebrate RRM-containing coactivator activator/modulator (CoAA); This subgroup corresponds to the RRM1 of CoAA, also termed RNA-binding protein 14 (RBM14), or paraspeckle protein 2 (PSP2), or synaptotagmin-interacting protein (SYT-interacting protein), a heterogeneous nuclear ribonucleoprotein (hnRNP)-like protein identified as a nuclear receptor coactivator. It mediates transcriptional coactivation and RNA splicing effects in a promoter-preferential manner and is enhanced by thyroid hormone receptor-binding protein (TRBP). CoAA contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a TRBP-interacting domain. It stimulates transcription through its interactions with coactivators, such as TRBP and CREB-binding protein CBP/p300, via the TRBP-interacting domain and interaction with an RNA-containing complex, such as DNA-dependent protein kinase-poly(ADP-ribose) polymerase complexes, via the RRMs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1034575770   2 VKLFIGNLPREATEQEIRSLFEQYGKVLECDIIKNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEAS 70
Cdd:cd12608     1 MKIFVGNVDEDTSQEELSALFEPYGAVLSCAVMKQFAFVHMRGEAAADRAIRELNGRELHGRALVVEES 69

RNA recognition motif (RRM) superfamily; RRM, also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), is a highly abundant domain in eukaryotes found in proteins involved in post-transcriptional gene expression processes including mRNA and rRNA processing, RNA export, and RNA stability. This domain is 90 amino acids in length and consists of a four-stranded beta-sheet packed against two alpha-helices. RRM usually interacts with ssRNA, but is also known to interact with ssDNA as well as proteins. RRM binds a variable number of nucleotides, ranging from two to eight. The active site includes three aromatic side-chains located within the conserved RNP1 and RNP2 motifs of the domain. The RRM domain is found in a variety heterogeneous nuclear ribonucleoproteins (hnRNPs), proteins implicated in regulation of alternative splicing, and protein components of small nuclear ribonucleoproteins (snRNPs).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034575770  80 LHVGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQ 144
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDrdgkskgFAFVEFESPEDAEKALEALNGTELGGRPLKVS 72

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1034575770  77 STKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHV 143
Cdd:COG0724     1 SMKIYVGNLPYSVTEEDLRELFSEYGEVTSVKLITDretgrsrgFGFVEMPDDEEAQAAIEALNGAELMGRTLKV 75

polyadenylate binding protein, human types 1, 2, 3, 4 family; These eukaryotic proteins recognize the poly-A of mRNA and consists of four tandem RNA recognition domains at the N-terminus (rrm: pfam00076) followed by a PABP-specific domain (pfam00658) at the C-terminus. The protein is involved in the transport of mRNA's from the nucleus to the cytoplasm. There are four paralogs in Homo sapiens which are expressed in testis, platelets, broadly expressed and of unknown tissue range.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770   4 LFIGNLPREATEQEIRSLFEQYGKVLECDII-------KNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEASKNKS-- 74
Cdd:TIGR01628  91 IFVKNLDKSVDNKALFDTFSKFGNILSCKVAtdengksRGYGFVHFEKEESAKAAIQKVNGMLLNDKEVYVGRFIKKHer 170

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770  75 -----KASTKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAEDAVEAIRGLDNTEF----QG 138
Cdd:TIGR01628 171 eaaplKKFTNLYVKNLDPSVNEDKLRELFAKFGEITSAAVMKDgsgrsrgFAFVNFEKHEDAAKAVEEMNGKKIglakEG 250

                         170
                  ....*....|.
gi 1034575770 139 KRMHVQLSTSR 149
Cdd:TIGR01628 251 KKLYVGRAQKR 261

RNA recognition motif 2 (RRM2) found in vertebrate RRM-containing coactivator activator/modulator (CoAA); This subgroup corresponds to the RRM2 of CoAA, also termed RNA-binding protein 14 (RBM14), or paraspeckle protein 2 (PSP2), or synaptotagmin-interacting protein (SYT-interacting protein), a heterogeneous nuclear ribonucleoprotein (hnRNP)-like protein identified as a nuclear receptor coactivator. It mediates transcriptional coactivation and RNA splicing effects in a promoter-preferential manner and is enhanced by thyroid hormone receptor-binding protein (TRBP). CoAA contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a TRBP-interacting domain. It stimulates transcription through its interactions with coactivators, such as TRBP and CREB-binding protein CBP/p300, via the TRBP-interacting domain and interaction with an RNA-containing complex, such as DNA-dependent protein kinase-poly(ADP-ribose) polymerase complexes, via the RRMs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034575770   2 VKLFIGNLPREATEQEIRSLFEQYGKVLECDIIKNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVE 68
Cdd:cd12609     1 WKIFVGNVSATCTSDELRGLFEEFGRVVECDKVKDYAFVHMEREEEALAAIEALNGKEVKGRRINVE 67

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034575770  82 VGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAEDAVEAIRGLDNTEFQGKRMH 142
Cdd:pfam00076   3 VGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDetgrskgFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in CELF/Bruno-like family of RNA binding proteins and plant flowering time control protein FCA; This subfamily corresponds to the RRM1 and RRM2 domains of the CUGBP1 and ETR-3-like factors (CELF) as well as plant flowering time control protein FCA. CELF, also termed BRUNOL (Bruno-like) proteins, is a family of structurally related RNA-binding proteins involved in regulation of pre-mRNA splicing in the nucleus, and control of mRNA translation and deadenylation in the cytoplasm. The family contains six members: CELF-1 (also known as BRUNOL-2, CUG-BP1, NAPOR, EDEN-BP), CELF-2 (also known as BRUNOL-3, ETR-3, CUG-BP2, NAPOR-2), CELF-3 (also known as BRUNOL-1, TNRC4, ETR-1, CAGH4, ER DA4), CELF-4 (BRUNOL-4), CELF-5 (BRUNOL-5) and CELF-6 (BRUNOL-6). They all contain three highly conserved RNA recognition motifs (RRMs), also known as RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains): two consecutive RRMs (RRM1 and RRM2) situated in the N-terminal region followed by a linker region and the third RRM (RRM3) close to the C-terminus of the protein. The low sequence conservation of the linker region is highly suggestive of a large variety in the co-factors that associate with the various CELF family members. Based on both, sequence similarity and function, the CELF family can be divided into two subfamilies, the first containing CELFs 1 and 2, and the second containing CELFs 3, 4, 5, and 6. The different CELF proteins may act through different sites on at least some substrates. Furthermore, CELF proteins may interact with each other in varying combinations to influence alternative splicing in different contexts. This subfamily also includes plant flowering time control protein FCA that functions in the posttranscriptional regulation of transcripts involved in the flowering process. FCA contains two RRMs, and a WW protein interaction domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKNY--------GFVHIEDKTAAEDAIRNLHH-YKLHGVN 64
Cdd:cd12361     1 KLFVGMIPKTASEEDVRPLFEQFGNIEEVQILRDKqtgqskgcAFVTFSTREEALRAIEALHNkKTMPGCS 71

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 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHV 143
Cdd:cd21608     1 KLYVGNLSWDTTEDDLRDLFSEFGEVESAKVITDretgrsrgFGFVTFSTAEAAEAAIDALNGKELDGRSIVV 73

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 1034575770   4 LFIGNLPREATEQEIRSLFEQYGKVLECDII--------KNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVE 68
Cdd:cd12398     3 VFVGNIPYDATEEQLKEIFSEVGPVVSFRLVtdretgkpKGYGFCEFRDAETALSAVRNLNGYELNGRPLRVD 75

RNA recognition motif 3 (RRM3) found in heterogeneous nuclear ribonucleoprotein R (hnRNP R) and similar proteins; This subfamily corresponds to the RRM3 in hnRNP R, hnRNP Q, and APOBEC-1 complementation factor (ACF). hnRNP R is a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches and has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP Q is also a ubiquitously expressed nuclear RNA-binding protein. It has been identified as a component of the spliceosome complex, as well as a component of the apobec-1 editosome, and has been implicated in the regulation of specific mRNA transport. ACF is an RNA-binding subunit of a core complex that interacts with apoB mRNA to facilitate C to U RNA editing. It may also act as an apoB mRNA recognition factor and chaperone and play a key role in cell growth and differentiation. This family also includes two functionally unknown RNA-binding proteins, RBM46 and RBM47. All members contain three conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034575770   2 VK-LFIGNLPREATEQEIRSLFEQYGKVLECDIIKNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEASK 71
Cdd:cd12251     1 VKvLYVRNLMLSTTEEKLRELFSEYGKVERVKKIKDYAFVHFEERDDAVKAMEEMNGKELEGSEIEVSLAK 71

RNA recognition motif 1 (RRM1) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM1 of RBM28 and Nop4p. RBM28 is a specific nucleolar component of the spliceosomal small nuclear ribonucleoproteins (snRNPs), possibly coordinating their transition through the nucleolus. It specifically associates with U1, U2, U4, U5, and U6 small nuclear RNAs (snRNAs), and may play a role in the maturation of both small nuclear and ribosomal RNAs. RBM28 has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an extremely acidic region between RRM2 and RRM3. The family also includes nucleolar protein 4 (Nop4p or Nop77p) encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p also contains four RRMs.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQLSTSR 149
Cdd:cd12413     1 TLFVRNLPYDTTDEQLEELFSDVGPVKRCFVVKDkgkdkcrgFGYVTFALAEDAQRALEEVKGKKFGGRKIKVELAKKK 79

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEASK 71
Cdd:cd12337     1 RVYIGRLPYRARERDVERFFRGYGRIRDINLKNGFGFVEFEDPRDADDAVYELNGKELCGERVIVEHAR 69

RNA recognition motif 3 (RRM3) found in RNA-binding protein 19 (RBM19) and RNA recognition motif 2 found in multiple RNA-binding domain-containing protein 1 (MRD1); This subfamily corresponds to the RRM3 of RBM19 and RRM2 of MRD1. RBM19, also termed RNA-binding domain-1 (RBD-1), is a nucleolar protein conserved in eukaryotes involved in ribosome biogenesis by processing rRNA and is essential for preimplantation development. It has a unique domain organization containing 6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). MRD1 is encoded by a novel yeast gene MRD1 (multiple RNA-binding domain). It is well conserved in yeast and its homologs exist in all eukaryotes. MRD1 is present in the nucleolus and the nucleoplasm. It interacts with the 35 S precursor rRNA (pre-rRNA) and U3 small nucleolar RNAs (snoRNAs). It is essential for the initial processing at the A0-A2 cleavage sites in the 35 S pre-rRNA. MRD1 contains 5 conserved RRMs, which may play an important structural role in organizing specific rRNA processing events.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHV 143
Cdd:cd12316     1 RLFVRNLPFTATEDELRELFEAFGKISEVHIPLDkqtkrskgFAFVLFVIPEDAVKAYQELDGSIFQGRLLHV 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770   4 LFIGNLPREATEQEIRSLFEQYGKVLECDIIKN-------YGFVHIEDKTAAEDAIRNLHHYKLHGV------------- 63
Cdd:TIGR01628 181 LYVKNLDPSVNEDKLRELFAKFGEITSAAVMKDgsgrsrgFAFVNFEKHEDAAKAVEEMNGKKIGLAkegkklyvgraqk 260

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034575770  64 -------------NINVEaSKNKSKASTkLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAED 123
Cdd:TIGR01628 261 raereaelrrkfeELQQE-RKMKAQGVN-LYVKNLDDTVTDEKLRELFSECGEITSAKVMLDekgvsrgFGFVCFSNPEE 338

                         170       180
                  ....*....|....*....|....*.
gi 1034575770 124 AVEAIRGLDNTEFQGKRMHVQLSTSR 149
Cdd:TIGR01628 339 ANRAVTEMHGRMLGGKPLYVALAQRK 364

RNA recognition motif (RRM) found in the scaffold attachment factor (SAFB) family; This subfamily corresponds to the RRM domain of the SAFB family, including scaffold attachment factor B1 (SAFB1), scaffold attachment factor B2 (SAFB2), SAFB-like transcriptional modulator (SLTM), and similar proteins, which are ubiquitously expressed. SAFB1, SAFB2 and SLTM have been implicated in many diverse cellular processes including cell growth and transformation, stress response, and apoptosis. They share high sequence similarities and all contain a scaffold attachment factor-box (SAF-box, also known as SAP domain) DNA-binding motif, an RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a region rich in glutamine and arginine residues. SAFB1 is a nuclear protein with a distribution similar to that of SLTM, but unlike that of SAFB2, which is also found in the cytoplasm. To a large extent, SAFB1 and SLTM might share similar functions, such as the inhibition of an oestrogen reporter gene. The additional cytoplasmic localization of SAFB2 implies that it could play additional roles in the cytoplasmic compartment which are distinct from the nuclear functions shared with SAFB1 and SLTM.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHV 143
Cdd:cd12417     1 NLWISGLSDTTKAADLKKIFSKYGKVVSAKVVTSartpgsrcYGYVTMASVEEADLCIKSLNKTELHGRVITV 73

RNA recognition motif 3 (RRM3) found in heterogeneous nuclear ribonucleoprotein R (hnRNP R) and similar proteins; This subfamily corresponds to the RRM3 in hnRNP R, hnRNP Q, and APOBEC-1 complementation factor (ACF). hnRNP R is a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches and has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP Q is also a ubiquitously expressed nuclear RNA-binding protein. It has been identified as a component of the spliceosome complex, as well as a component of the apobec-1 editosome, and has been implicated in the regulation of specific mRNA transport. ACF is an RNA-binding subunit of a core complex that interacts with apoB mRNA to facilitate C to U RNA editing. It may also act as an apoB mRNA recognition factor and chaperone and play a key role in cell growth and differentiation. This family also includes two functionally unknown RNA-binding proteins, RBM46 and RBM47. All members contain three conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1034575770  80 LHVGNISPTCTNQELRAKFEEYGPVIECDIVKDYAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQL 145
Cdd:cd12251     4 LYVRNLMLSTTEEKLRELFSEYGKVERVKKIKDYAFVHFEERDDAVKAMEEMNGKELEGSEIEVSL 69

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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKN---YGFVHIEDKTAAEDAIRNLHHYKLHGVNINVEASKN 72
Cdd:cd12373     1 KVYVGNLGPRVTKRELEDAFEKYGPLRNVWVARNppgFAFVEFEDPRDAEDAVRALDGRRICGSRVRVELSRG 73

RNA recognition motif 2 (RRM2) found in plant flowering time control protein FCA and similar proteins; This subgroup corresponds to the RRM2 of FCA, a gene controlling flowering time in Arabidopsis, which encodes a flowering time control protein that functions in the posttranscriptional regulation of transcripts involved in the flowering process. The flowering time control protein FCA contains two RNA recognition motifs (RRMs), also known as RBDs (RNA binding domains) or RNP (ribonucleoprotein domains), and a WW protein interaction domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKNY--------GFVHIEDKTAAEDAIRNLH-HYKLHGVNINVE 68
Cdd:cd12637     1 KLFVGSLPKTATEQEVRDLFEAYGEVEEVYLMKDPvtqqgtgcAFVKFAYKEEALAAIRSLNgTVTFDGCSRPVE 75

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 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD-------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHV 143
Cdd:cd12412     4 RIFVGGIDWDTTEEELREFFSKFGKVKDVKIIKDragvskgYGFVTFETQEDAEKIQKWGANLVFKGKKLNV 75

RNA recognition motif 1 (RRM1) found in vertebrate 54 kDa nuclear RNA- and DNA-binding protein (p54nrb); This subgroup corresponds to the RRM1 of p54nrb, also termed non-POU domain-containing octamer-binding protein (NonO), or 55 kDa nuclear protein (NMT55), or DNA-binding p52/p100 complex 52 kDa subunit. p54nrb is a multifunctional 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. It is ubiquitously expressed and highly conserved in vertebrates. p54nrb binds both, single- and double-stranded RNA and DNA, and also possesses inherent carbonic anhydrase activity. It forms a heterodimer with paraspeckle component 1 (PSPC1 or PSP1), localizing to paraspeckles in an RNA-dependent manneras well as with polypyrimidine tract-binding protein-associated-splicing factor (PSF). p54nrb contains two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), at the N-terminus.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKN--YGFVHIEDKTAAEDAIRNLHHYKLHGVNINV 67
Cdd:cd12588     3 RLFVGNLPPDITEEEMRKLFEKYGKAGEVFIHKDkgFGFIRLETRTLAEIAKVELDNMPLRGKQLRV 69

RNA recognition motif 1 (RRM1) found in serine/arginine-rich splicing factor 1 (SRSF1) and similar proteins; This subgroup corresponds to the RRM1 in three serine/arginine (SR) proteins: serine/arginine-rich splicing factor 1 (SRSF1 or ASF-1), serine/arginine-rich splicing factor 9 (SRSF9 or SRp30C), and plant pre-mRNA-splicing factor SF2 (SR1). SRSF1 is a shuttling SR protein involved in constitutive and alternative splicing, nonsense-mediated mRNA decay (NMD), mRNA export and translation. It also functions as a splicing-factor oncoprotein that regulates apoptosis and proliferation to promote mammary epithelial cell transformation. SRSF9 has been implicated in the activity of many elements that control splice site selection, the alternative splicing of the glucocorticoid receptor beta in neutrophils and in the gonadotropin-releasing hormone pre-mRNA. It can also interact with other proteins implicated in alternative splicing, including YB-1, rSLM-1, rSLM-2, E4-ORF4, Nop30, and p32. Both, SRSF1 and SRSF9, contain two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RS domains rich in serine-arginine dipeptides. In contrast, SF2 contains two N-terminal RRMs and a C-terminal PSK domain rich in proline, serine and lysine residues.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034575770   3 KLFIGNLPREATEQEIRSLFEQYGKVLECDIIKN-----YGFVHIEDKTAAEDAIRNLHHYKLHGVNINVE 68
Cdd:cd12338     1 RIYVGNLPGDIRERDIEDLFYKYGPILAIDLKNRrrgppFAFVEFEDPRDAEDAIRGRDGYDFDGYRLRVE 71

RNA recognition motif (RRM) found in transformer-2 protein homolog TRA2-alpha, TRA2-beta and similar proteins; This subfamily corresponds to the RRM of two mammalian homologs of Drosophila transformer-2 (Tra2), TRA2-alpha, TRA2-beta (also termed SFRS10), and similar proteins found in eukaryotes. TRA2-alpha is a 40-kDa serine/arginine-rich (SR) protein 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-beta is a serine/arginine-rich (SR) protein that controls the pre-mRNA alternative splicing of the calcitonin/calcitonin gene-related peptide (CGRP), the survival motor neuron 1 (SMN1) protein and the tau protein. Both, TRA2-alpha and TRA2-beta, 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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1034575770  77 STKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--------YAFVHMERAEDAVEAIRGLDNTEFQGKRMHVQLS 146
Cdd:cd12363     1 SRCLGVFGLSLYTTERDLREVFSRYGPIEKVQVVYDqqtgrsrgFGFVYFESVEDAKEAKERLNGQEIDGRRIRVDYS 78

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1034575770  78 TKLHVGNISPTCTNQELRAKFEEYGPVIECDIVKD--YAFVHMERAEDAVEAIRGLDNTEFQGK 139
Cdd:cd12354     1 TTVYVGNITKGLTEALLQQTFSPFGQILEVRVFPDkgYAFIRFDSHEAATHAIVSVNGTIINGQ 64

RNA recognition motif (RRM) found in fission yeast pre-mRNA-splicing factor Srp1p, Arabidopsis thaliana arginine/serine-rich-splicing factor RSp31 and similar proteins; This subfamily corresponds to the RRM of Srp1p and RRM2 of plant SR splicing factors. Srp1p is encoded by gene srp1 from fission yeast Schizosaccharomyces pombe. It plays a role in the pre-mRNA splicing process, but is not essential for growth. Srp1p is closely related to the SR protein family found in Metazoa. It contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a glycine hinge and a RS domain in the middle, and a C-terminal domain. The family also includes a novel group of arginine/serine (RS) or serine/arginine (SR) splicing factors existing in plants, such as A. thaliana RSp31, RSp35, RSp41 and similar proteins. Like vertebrate RS splicing factors, these proteins function as plant splicing factors and play crucial roles in constitutive and alternative splicing in plants. They all contain two RRMs at their N-terminus and an RS domain at their C-terminus.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1034575770   4 LFIGNL-PREATEQEIRSLFEQYGKVLECDIIKNYGFVHIEDKTAAEDAIRNLHHYKLHGVNINVE 68
Cdd:cd12233     2 LFVVGFdPGTTREEDIEKLFEPFGPLVRCDIRKTFAFVEFEDSEDATKALEALHGSRIDGSVLTVE 67

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in CELF/Bruno-like family of RNA binding proteins and plant flowering time control protein FCA; This subfamily corresponds to the RRM1 and RRM2 domains of the CUGBP1 and ETR-3-like factors (CELF) as well as plant flowering time control protein FCA. CELF, also termed BRUNOL (Bruno-like) proteins, is a family of structurally related RNA-binding proteins involved in regulation of pre-mRNA splicing in the nucleus, and control of mRNA translation and deadenylation in the cytoplasm. The family contains six members: CELF-1 (also known as BRUNOL-2, CUG-BP1, NAPOR, EDEN-BP), CELF-2 (also known as BRUNOL-3, ETR-3, CUG-BP2, NAPOR-2), CELF-3 (also known as BRUNOL-1, TNRC4, ETR-1, CAGH4, ER DA4), CELF-4 (BRUNOL-4), CELF-5 (BRUNOL-5) and CELF-6 (BRUNOL-6). They all contain three highly conserved RNA recognition motifs (RRMs), also known as RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains): two consecutive RRMs (RRM1 and RRM2) situated in the N-terminal region followed by a linker region and the third RRM (RRM3) close to the C-terminus of the protein. The low sequence conservation of the linker region is highly suggestive of a large variety in the co-factors that associate with the various CELF family members. Based on both, sequence similarity and function, the CELF family can be divided into two subfamilies, the first containing CELFs 1 and 2, and the second containing CELFs 3, 4, 5, and 6. The different CELF proteins may act through different sites on at least some substrates. Furthermore, CELF proteins may interact with each other in varying combinations to influence alternative splicing in different contexts. This subfamily also includes plant flowering time control protein FCA that functions in the posttranscriptional regulation of transcripts involved in the flowering process. FCA contains two RRMs, and a WW protein interaction domain.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1034575770  79 KLHVGNISPTCTNQELRAKFEEYGPVIECDIVKDY--------AFVHMERAEDAVEAIRGLDNT 134
Cdd:cd12361     1 KLFVGMIPKTASEEDVRPLFEQFGNIEEVQILRDKqtgqskgcAFVTFSTREEALRAIEALHNK 64