RNA recognition motif (RRM) found in Eukaryotic CCR4-NOT transcription complex subunit 4 (NOT4) and similar proteins; This subfamily corresponds to the RRM of NOT4, also termed CCR4-associated factor 4, or E3 ubiquitin-protein ligase CNOT4, or potential transcriptional repressor NOT4Hp, a component of the CCR4-NOT complex, a global negative regulator of RNA polymerase II transcription. NOT4 functions as an ubiquitin-protein ligase (E3). It contains an N-terminal C4C4 type RING finger motif, followed by a RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The RING fingers may interact with a subset of ubiquitin-conjugating enzymes (E2s), including UbcH5B, and mediate protein-protein interactions. T

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334188516 105 RVIQRNLVYIVGLPLNLADEDLLQHKEYFGQYGKVLKVSMSRTASGVIQQfpNNTCSVYITYGKEEEAVRCIQAVHGFIL 184
Cdd:cd12438    1 RVVQKNLVYVVGLPPRLADEEVLKRPEYFGQYGKIKKIVINRSTSYAGSQ--GPSASAYVTYSRKEDALRAIQAVDGFVL 78

                         90       100
                 ....*....|....*....|
gi 334188516 185 DGKPLKACFGTTKYCHAWLR 204
Cdd:cd12438   79 DGRTLKASFGTTKYCSSFLR 98

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 334188516   112 VYIVGLPLNLADEDLlqhKEYFGQYGKVLKVSMSRTasgviQQFPNNTCSVYITYGKEEEAVRCIQAVHGFILDGKPLK 190
Cdd:smart00360   2 LFVGNLPPDTTEEEL---RELFSKFGKVESVRLVRD-----KETGKSKGFAFVEFESEEDAEKALEALNGKELDGRPLK 72

RNA recognition motif (RRM) found in Eukaryotic CCR4-NOT transcription complex subunit 4 (NOT4) and similar proteins; This subfamily corresponds to the RRM of NOT4, also termed CCR4-associated factor 4, or E3 ubiquitin-protein ligase CNOT4, or potential transcriptional repressor NOT4Hp, a component of the CCR4-NOT complex, a global negative regulator of RNA polymerase II transcription. NOT4 functions as an ubiquitin-protein ligase (E3). It contains an N-terminal C4C4 type RING finger motif, followed by a RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The RING fingers may interact with a subset of ubiquitin-conjugating enzymes (E2s), including UbcH5B, and mediate protein-protein interactions. T

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334188516 105 RVIQRNLVYIVGLPLNLADEDLLQHKEYFGQYGKVLKVSMSRTASGVIQQfpNNTCSVYITYGKEEEAVRCIQAVHGFIL 184
Cdd:cd12438    1 RVVQKNLVYVVGLPPRLADEEVLKRPEYFGQYGKIKKIVINRSTSYAGSQ--GPSASAYVTYSRKEDALRAIQAVDGFVL 78

                         90       100
                 ....*....|....*....|
gi 334188516 185 DGKPLKACFGTTKYCHAWLR 204
Cdd:cd12438   79 DGRTLKASFGTTKYCSSFLR 98

Modified RING finger, HC subclass (C4C4-type), found in CCR4-NOT transcription complex subunit 4 (NOT4) and similar proteins; NOT4, also known as CCR4-associated factor 4, E3 ubiquitin-protein ligase CNOT4, or potential transcriptional repressor NOT4, is a component of the multifunctional CCR4-NOT complex, a global regulator of RNA polymerase II transcription. It associates with polysomes and contributes to the negative regulation of protein synthesis. NOT4 functions as an E3 ubiquitin-protein ligase that interacts with a specific E2, Ubc4/5 in yeast, and the ortholog UbcH5B in humans, and ubiquitylates a wide range of substrates, including ribosome-associated factors. Thus, it plays a role in cotranslational quality control (QC) through ribosome-associated ubiquitination and degradation of aberrant peptides. NOT4 contains a C4C4-type RING finger motif, whose overall folding is similar to that of the C3HC4-type RING-HC finger, a central RNA recognition motif (RRM), and a C-terminal domain predicted to be unstructured.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 334188516   7 KTCPLCAEEMDLTDQQLKPCKCGYQICVWCWHHIvdmaeKDQIEGRCPACRT 58
Cdd:cd16618    1 PECPLCMEELDITDLNFFPCPCGYQICLFCWHRI-----REDENGRCPACRK 47

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 334188516   112 VYIVGLPLNLADEDLlqhKEYFGQYGKVLKVSMSRTasgviQQFPNNTCSVYITYGKEEEAVRCIQAVHGFILDGKPLK 190
Cdd:smart00360   2 LFVGNLPPDTTEEEL---RELFSKFGKVESVRLVRD-----KETGKSKGFAFVEFESEEDAEKALEALNGKELDGRPLK 72

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 334188516   123 DEDLLQHK----EYFGQYGKVLKVSMSRTASGVIQQFpnntcSVYITYGKEEEAVRCIQAVHGFILDGKPLKAC 192
Cdd:smart00361   2 DEDFERELkeeeEYFGEVGKINKIYIDDVGYENHKRG-----NVYITFERSEDAARAIVDLNGRYFDGRLVKAE 70

RNA recognition motif 3 (RRM3) found found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM3 of type I poly(A)-binding proteins (PABPs), highly conserved proteins that bind to the poly(A) tail present at the 3' ends of most eukaryotic mRNAs. They have been implicated in the regulation of poly(A) tail length during the polyadenylation reaction, translation initiation, mRNA stabilization by influencing the rate of deadenylation and inhibition of mRNA decapping. The family represents type I polyadenylate-binding proteins (PABPs), including polyadenylate-binding protein 1 (PABP-1 or PABPC1), polyadenylate-binding protein 3 (PABP-3 or PABPC3), polyadenylate-binding protein 4 (PABP-4 or APP-1 or iPABP), polyadenylate-binding protein 5 (PABP-5 or PABPC5), polyadenylate-binding protein 1-like (PABP-1-like or PABPC1L), polyadenylate-binding protein 1-like 2 (PABPC1L2 or RBM32), polyadenylate-binding protein 4-like (PABP-4-like or PABPC4L), yeast polyadenylate-binding protein, cytoplasmic and nuclear (PABP or ACBP-67), and similar proteins. PABP-1 is an ubiquitously expressed multifunctional protein that may play a role in 3' end formation of mRNA, translation initiation, mRNA stabilization, protection of poly(A) from nuclease activity, mRNA deadenylation, inhibition of mRNA decapping, and mRNP maturation. Although PABP-1 is thought to be a cytoplasmic protein, it is also found in the nucleus. PABP-1 may be involved in nucleocytoplasmic trafficking and utilization of mRNP particles. PABP-1 contains four copies of RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), a less well conserved linker region, and a proline-rich C-terminal conserved domain (CTD). PABP-3 is a testis-specific poly(A)-binding protein specifically expressed in round spermatids. It is mainly found in mammalian and may play an important role in the testis-specific regulation of mRNA homeostasis. PABP-3 shows significant sequence similarity to PABP-1. However, it binds to poly(A) with a lower affinity than PABP-1. PABP-1 possesses an A-rich sequence in its 5'-UTR and allows binding of PABP and blockage of translation of its own mRNA. In contrast, PABP-3 lacks the A-rich sequence in its 5'-UTR. PABP-4 is an inducible poly(A)-binding protein (iPABP) that is primarily localized to the cytoplasm. It shows significant sequence similarity to PABP-1 as well. The RNA binding properties of PABP-1 and PABP-4 appear to be identical. PABP-5 is encoded by PABPC5 gene within the X-specific subinterval, and expressed in fetal brain and in a range of adult tissues in mammalian, such as ovary and testis. It may play an important role in germ cell development. Moreover, unlike other PABPs, PABP-5 contains only four RRMs, but lacks both the linker region and the CTD. PABP-1-like and PABP-1-like 2 are the orthologs of PABP-1. PABP-4-like is the ortholog of PABP-5. Their cellular functions remain unclear. The family also includes the yeast PABP, a conserved poly(A) binding protein containing poly(A) tails that can be attached to the 3'-ends of mRNAs. The yeast PABP and its homologs may play important roles in the initiation of translation and in mRNA decay. Like vertebrate PABP-1, the yeast PABP contains four RRMs, a linker region, and a proline-rich CTD as well. The first two RRMs are mainly responsible for specific binding to poly(A). The proline-rich region may be involved in protein-protein interactions.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 334188516 112 VYIVGLPLNLADEDLlqhKEYFGQYGKVLKVSMSRTASGVIQQFPnntcsvYITYGKEEEAVRCIQAVHGFILDGKPL 189
Cdd:cd12380    4 VYVKNFGEDVDDDEL---KELFEKYGKITSAKVMKDDSGKSKGFG------FVNFENHEAAQKAVEELNGKELNGKKL 72

RING finger, HC subclass, found in Arabidopsis thaliana proteolysis 1 protein (PRT1) and similar proteins; PRT1, also called RING-type E3 ubiquitin transferase PRT1, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of target proteins. It functions in the N-end rule pathway of protein degradation, where it specifically recognizes and ubiquitinates proteins with an N-terminal bulky aromatic amino acid (Phe). It does not act on aliphatic hydrophobic and basic N-terminal residues (Arg or Leu) containing proteins. PRT1 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 334188516   6 EKTCPLCAEEMdltdqqLKPC--KCGYQICVWCWHHIVDMAEKDqiegRCPACRTPYDK 62
Cdd:cd23132    2 EFLCCICLDLL------YKPVvlECGHVFCFWCVHRCMNGYDES----HCPLCRRPYDH 50

RING finger, HC subclass, found in Schizosaccharomyces pombe DNA repair protein Rad8 (SpRad8) and similar proteins; SpRad8 is a conserved protein homologous to Saccharomyces cerevisiae DNA repair protein Rad5 and human helicase-like transcription factor (HLTF) that is required for error-free postreplication repair by contributing to polyubiquitylation of PCNA. SpRad8 contains a C3HC4-type RING-HC finger responsible for the E3 ubiquitin ligase activity, a SNF2-family helicase domain including an ATP binding site, and a family-specific HIRAN domain (HIP116, Rad5p N-terminal domain) that contributes to nuclear localization.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 334188516   3 DHGEKTCPLCAEEMdLTDQQLKPCKcgYQICVWCWHHIVDMAEKDQIEGRCPACRTPYDKEKI 65
Cdd:cd16572    1 EDAENECPICAEEP-ISELALTRCW--HSACKDCLLDHIEFQKSKNEVPLCPTCRQPINEQDI 60

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 334188516   9 CPLCAEEMDLTDQQLkPCKcgYQICVWCWHHIvdmaEKDQIEGRCPACRTP 59
Cdd:cd16749    3 CPVCFEKLDVTAKVL-PCQ--HTFCKPCLQRI----FKARKELRCPECRTP 46

RNA recognition motif (RRM) found in UHM domain of 45 kDa-splicing factor (SPF45) and similar proteins; This subfamily corresponds to the RRM found in UHM domain of 45 kDa-splicing factor (SPF45 or RBM17), poly(U)-binding-splicing factor PUF60 (FIR or Hfp or RoBP1 or Siah-BP1), and similar proteins. SPF45 is an RNA-binding protein consisting of an unstructured N-terminal region, followed by a G-patch motif and a C-terminal U2AF (U2 auxiliary factor) homology motifs (UHM) that harbors a RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain) and an Arg-Xaa-Phe sequence motif. SPF45 regulates alternative splicing of the apoptosis regulatory gene FAS (also known as CD95). It induces exon 6 skipping in FAS pre-mRNA through the UHM domain that binds to tryptophan-containing linear peptide motifs (UHM ligand motifs, ULMs) present in the 3' splice site-recognizing factors U2AF65, SF1 and SF3b155. PUF60 is an essential splicing factor that functions as a poly-U RNA-binding protein required to reconstitute splicing in depleted nuclear extracts. Its function is enhanced through interaction with U2 auxiliary factor U2AF65. PUF60 also controls human c-myc gene expression by binding and inhibiting the transcription factor far upstream sequence element (FUSE)-binding-protein (FBP), an activator of c-myc promoters. PUF60 contains two central RRMs and a C-terminal UHM domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334188516 111 LVYIVGLplNLADEDLLQH-KEYFGQYGKVLKVsmsrtasgVIQQFPNNTCS----VYITYGKEEEAVRCIQAVHGFILD 185
Cdd:cd12374    6 LRNMVGP--GEIDEDLKDEiKEECSKYGKVLNV--------IIHEVASSEADdavrVFVEFEDADEAIKAFRALNGRFFG 75

                 ....*...
gi 334188516 186 GKPLKACF 193
Cdd:cd12374   76 GRKVKARF 83

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 334188516 113 YIVGLPLNLADEDLlqhKEYFGQYGKVL--KVSMSRTASGviqqfpnNTCSVYITYGKEEEAVRCIQAVHGFILDGK 187
Cdd:cd12417    3 WISGLSDTTKAADL---KKIFSKYGKVVsaKVVTSARTPG-------SRCYGYVTMASVEEADLCIKSLNKTELHGR 69

RNA recognition motif 3 (RRM3) found in CELF/Bruno-like family of RNA binding proteins CELF1, CELF2, CELF3, CELF4, CELF5, CELF6 and similar proteins; This subgroup corresponds to the RRM3 of the CUGBP1 and ETR-3-like factors (CELF) or BRUNOL (Bruno-like) proteins, a family of structurally related RNA-binding proteins involved in the regulation of pre-mRNA splicing in the nucleus and in the control of mRNA translation and deadenylation in the cytoplasm. The family contains six members: CELF-1 (also termed BRUNOL-2, or CUG-BP1, or NAPOR, or EDEN-BP), CELF-2 (also termed BRUNOL-3, or ETR-3, or CUG-BP2, or NAPOR-2), CELF-3 (also termed BRUNOL-1, or TNRC4, or ETR-1, or CAGH4, or ER DA4), CELF-4 (also termed BRUNOL-4), CELF-5 (also termed BRUNOL-5), CELF-6 (also termed 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334188516 112 VYIVGLPLNLADEDLLQHkeyFGQYGKVL--KVSMSRTASgviqqfpNNTCSVYITYGKEEEAVRCIQAVHGFILDGKPL 189
Cdd:cd12362    1 LFVYHLPNEFTDQDLYQL---FAPFGNVVsaKVFVDKNTG-------RSKGFGFVSYDNPLSAQAAIKAMNGFQVGGKRL 70

                 .
gi 334188516 190 K 190
Cdd:cd12362   71 K 71

RING finger, HC subclass, found in tripartite motif-containing protein 32 (TRIM32) and similar proteins; TRIM32, also known as 72 kDa Tat-interacting protein, zinc finger protein HT2A, or BBS11, is an E3 ubiquitin-protein ligase that promotes degradation of several targets, including actin, PIASgamma, Abl interactor 2, dysbindin, X-linked inhibitor of apoptosis (XIAP), p73 transcription factor, thin filaments and Z-bands during fasting. It plays important roles in neuronal differentiation of neural progenitor cells, as well as in controlling cell fate in skeletal muscle progenitor cells. It reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation. It also functions as a pluripotency-reprogramming roadblock that facilitates cellular transition towards differentiation by modulating the levels of Oct4 and cMyc. Moreover, TRIM32 is an intrinsic influenza A virus (IAV) restriction factor which senses and targets the polymerase basic protein 1 (PB1) for ubiquitination and protein degradation. It also plays a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo, binds specifically to the activation domain of HIV-1 Tat, and can also interact with the HIV-2 and EIAV Tat proteins in vivo. Furthermore, TRIM32 regulates myoblast proliferation by controlling turnover of NDRG2 (N-myc downstream-regulated gene). It negatively regulates tumor suppressor p53 to promote tumorigenesis. It also facilitates degradation of MYCN on spindle poles and induces asymmetric cell division in human neuroblastoma cells. In addition, TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. It also plays a role in regeneration by affecting satellite cell cycle progression via modulation of the SUMO ligase PIASy (PIAS4). Defects in TRIM32 leads to limb-girdle muscular dystrophy type 2H (LGMD2H), sarcotubular myopathies (STM) and Bardet-Biedl syndrome. TRIM32 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain. The NHL domain mediates the interaction with Argonaute proteins and consequently allows TRIM32 to modulate the activity of certain miRNAs.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 334188516   8 TCPLCAEEMDltDQQLKP--CKCGYQICVWCWHHIVDMAEKDQIegRCPACR 57
Cdd:cd16587    2 ECPICLESFD--EGQLRPklLHCGHTICEQCLEKLLASLSINGV--RCPFCR 49

RNA recognition motif in negative elongation factor E (NELF-E) and similar proteins; This subfamily corresponds to the RRM of NELF-E, also termed RNA-binding protein RD. NELF-E is the RNA-binding subunit of cellular negative transcription elongation factor NELF (negative elongation factor) involved in transcriptional regulation of HIV-1 by binding to the stem of the viral transactivation-response element (TAR) RNA which is synthesized by cellular RNA polymerase II at the viral long terminal repeat. NELF is a heterotetrameric protein consisting of NELF A, B, C or the splice variant D, and E. NELF-E contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It plays a role in the control of HIV transcription by binding to TAR RNA. In addition, NELF-E is associated with the NELF-B subunit, probably via a leucine zipper motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334188516 107 IQRNLVYIVGLPLNladEDLLqhKEYFGQYGKVLKVSMSRtasgviqqfPNNtcSVYITYGKEEEAVRCIQAVHGFILDG 186
Cdd:cd12305    2 RKGNTVYVSGYGIT---EDVL--KKAFSPFGNIINISMEI---------EKN--CAFVTFEKMESADQAIAELNGTTVEG 65

                 ....
gi 334188516 187 KPLK 190
Cdd:cd12305   66 VQLK 69

RING finger, H2 subclass, found in Saccharomyces cerevisiae alcohol-sensitive RING finger protein 1 (ASR1) and similar proteins; ASR1 is required for tolerance to alcohol. It signals alcohol stress to the nucleus. ASR1 contains a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 334188516   9 CPLCAEEMDLTDQQLKPCKCGYQI-CVWCWHHIvdmaekdQIEGRCPACRT 58
Cdd:cd23120    4 CPICLEEMNSGTGYLADCGHEFHLtCIREWHNK-------SGNLDCPICRV 47

RNA recognition motif 2 (RRM2) found in HIV Tat-specific factor 1 (Tat-SF1) and similar proteins; This subfamily corresponds to the RRM2 of Tat-SF1 and CUS2. Tat-SF1 is the cofactor for stimulation of transcriptional elongation by human immunodeficiency virus-type 1 (HIV-1) Tat. It is a substrate of an associated cellular kinase. Tat-SF1 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a highly acidic carboxyl-terminal half. The family also includes CUS2, a yeast homolog of human Tat-SF1. CUS2 interacts with U2 RNA in splicing extracts and functions as a splicing factor that aids assembly of the splicing-competent U2 snRNP in vivo. CUS2 also associates with PRP11 that is a subunit of the conserved splicing factor SF3a. Like Tat-SF1, CUS2 contains two RRMs as well.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 334188516 124 EDLLQHKEYFGQYGKVLkvsmsrtasgVIQQFPNNTCSVyiTYGKEEEAVRCIQAVHGFILDGKPLKACF--GTTKY 198
Cdd:cd12282   27 EDLREECEKFGQVKKVV----------VFDRHPDGVASV--KFKEPEEADKCIQALNGRWFAGRKLEAETwdGKTDY 91

RNA recognition motif (RRM) found in eukaryotic RNA-binding protein 18 and similar proteins; This subfamily corresponds to the RRM of RBM18, a putative RNA-binding protein containing a well-conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The biological role of RBM18 remains unclear.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 334188516 112 VYIVGLPLNLADEDLLQhkeYFGQYGKVLKVSMSRTASGVIQQFPNNTCsvYITYGKEEEAVRCIQAVHGFILDGKPL 189
Cdd:cd12355    2 LWIGNLDPRLTEYHLLK---LLSKYGKIKKFDFLFHKTGPLKGQPRGYC--FVTFETKEEAEKAIECLNGKLALGKKL 74

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 1 (SH3RF1) and similar proteins; SH3RF1, also known as plenty of SH3s (POSH), RING finger protein 142 (RNF142), or SH3 multiple domains protein 2 (SH3MD2), is a trans-Golgi network-associated pro-apoptotic scaffold protein with E3 ubiquitin-protein ligase activity. It also plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and c-Jun N-terminal kinase (JNK) mediated apoptosis, linking Rac1 to downstream components. SH3RF1 also enhances the ubiquitination of ROMK1 potassium channel resulting in its increased endocytosis. Moreover, SH3RF1 assembles an inhibitory complex with the actomyosin regulatory protein Shroom3, which links to the actin-myosin network to regulate neuronal process outgrowth. It also forms a complex with apoptosis-linked gene-2 (ALG-2) and ALG-2-interacting protein (ALIX/AIP1) in a calcium-dependent manner to play a role in the regulation of the JNK pathway. Furthermore, direct interaction of SH3RF1 and another molecular scaffold JNK-interacting protein (JIP) is required for apoptotic activation of JNKs. Interaction of SH3RF1 and E3 ubiquitin-protein isopeptide ligases, Siah proteins, further promotes JNK activation and apoptosis. In addition, SH3RF1 binds to and degrades TAK1, a crucial activator of both the JNK and the Relish signaling pathways. SH3RF1 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 334188516   9 CPLCAEEMDLTDQQLkPCKcgYQICVWCWHHIVDmaekDQIEGRCPACRT 58
Cdd:cd16748    5 CPVCLERLDATAKVL-PCQ--HTFCRRCLLGIVG----SRSELRCPECRT 47

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

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gi 334188516 112 VYIVGLPLNLADEDLLQHkeyFGQYGKVL--KVSMSRTaSGVIQQFPnntcsvYITYGKEEEAVRCIQAVHGFILDGKPL 189
Cdd:cd21608    2 LYVGNLSWDTTEDDLRDL---FSEFGEVEsaKVITDRE-TGRSRGFG------FVTFSTAEAAEAAIDALNGKELDGRSI 71