NURR (N-terminal unit for RNA recognition) domain found in heterogeneous nuclear ribonucleoprotein R (hnRNPR) and similar proteins; hnRNPR is a highly conserved RNA-binding protein that belongs to the heterogeneous nuclear ribonucleoprotein (hnRNP) family. hnRNP plays an important role in processing of precursor mRNA in the nucleus. hnRNPR acts as a general positive regulator of MHC class I expression. The model corresponds to NURR domain of hnRNPR.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568  27 TEHYKTLIEAGLPQKVAERLDEIFQTGLVAYVDLDERAIDALREFNEEGALSVLQQFKESDLSHVQNKSAFLCGVMKTYR 106
Cdd:cd21067     1 TEHYQTLLEAGLPQKVAERLDEIFQTGLVAYADLDERAIDALREFNEEGALSVLQQFKESDLSHVQNKSAFLCGVMKTYR 80

                  ....
gi 1034554568 107 QREK 110
Cdd:cd21067    81 QREK 84

RNA recognition motif 2 (RRM2) found in vertebrate heterogeneous nuclear ribonucleoprotein R (hnRNP R); This subgroup corresponds to the RRM2 of hnRNP R, a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches. Upon binding of RNA, hnRNP R forms oligomers, most probably dimers. hnRNP R has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP R is predominantly located in axons of motor neurons and to a much lower degree in sensory axons. In axons of motor neurons, it also functions as a cytosolic protein and interacts with wild type of survival motor neuron (SMN) proteins directly, further providing a molecular link between SMN and the spliceosome. Moreover, hnRNP R plays an important role in neural differentiation and development, as well as in retinal development and light-elicited cellular activities. It contains an acidic auxiliary N-terminal region, followed by two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RGG motif. hnRNP R binds RNA through its RRM domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 185 ANNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTV 264
Cdd:cd12488     1 ANNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTV 80

                  ....*
gi 1034554568 265 EWADP 269
Cdd:cd12488    81 EWADP 85

Heterogeneous nuclear ribonucleoprotein Q acidic domain; This is an acidic sequence segment domain found in the splicing factor SYNCRIP (hnRNP Q) which is involved in viral replication, neural morphogenesis, modulation of circadian oscillation and the regulation of the cytidine deaminase APOBEC1. This domain is a self-folding globular domain with an all alpha-helix architecture with negatively charged surface areas. Additionally it contains a large hydrophobic cavity and a positively charged surface area as potential epitopes for inter-molecular interactions.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568  37 GLPQKVAERLDEIFQTGLVAYVDLDERAIDALREFNEEGALSVLQQFKESDLSHVQNKSAFLCGVMKTYR 106
Cdd:pfam18360   1 GLPPKVAEALDELYRSGKLAPSDLDDRALEALKSLPEDGALAVLKQFKESDLSGVSNKSAFLMGIMKTYR 70

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 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERV-------KKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIrlvrdetGRSKGFAFVEFEDEEDAEKAIEALNGK 62

glycine-rich RNA-binding protein 4; Provisional

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKD--------YAFVHFEDRGAAVKAMDEMNGK 338
Cdd:PLN03134   37 LFIGGLSWGTDDASLRDAFAHFGDVVDAKVIVDretgrsrgFGFVNFNDEGAATAAISEMDGK 99

RNA recognition motif 2 (RRM2) found in vertebrate heterogeneous nuclear ribonucleoprotein R (hnRNP R); This subgroup corresponds to the RRM2 of hnRNP R, a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches. Upon binding of RNA, hnRNP R forms oligomers, most probably dimers. hnRNP R has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP R is predominantly located in axons of motor neurons and to a much lower degree in sensory axons. In axons of motor neurons, it also functions as a cytosolic protein and interacts with wild type of survival motor neuron (SMN) proteins directly, further providing a molecular link between SMN and the spliceosome. Moreover, hnRNP R plays an important role in neural differentiation and development, as well as in retinal development and light-elicited cellular activities. It contains an acidic auxiliary N-terminal region, followed by two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RGG motif. hnRNP R binds RNA through its RRM domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 185 ANNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTV 264
Cdd:cd12488     1 ANNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTV 80

                  ....*
gi 1034554568 265 EWADP 269
Cdd:cd12488    81 EWADP 85

RNA recognition motif 2 (RRM2) found in heterogeneous nuclear ribonucleoprotein R (hnRNP R) and similar proteins; This subfamily corresponds to the RRM2 in hnRNP R, hnRNP Q, APOBEC-1 complementation factor (ACF), and dead end protein homolog 1 (DND1). hnRNP R is a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches. It 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. DND1 is essential for maintaining viable germ cells in vertebrates. It interacts with the 3'-untranslated region (3'-UTR) of multiple messenger RNAs (mRNAs) and prevents micro-RNA (miRNA) mediated repression of mRNA. This family also includes two functionally unknown RNA-binding proteins, RBM46 and RBM47. All members in this family, except for DND1, contain three conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains); DND1 harbors only two RRMs.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 186 NNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTVE 265
Cdd:cd12250     1 NNRLFVGGIPKTKTKEEILEEFSKVTEGVVDVIVYPSPDDKKKNRGFAFLEYESHKAAAIARRKLTPGRILLWGHDVAVD 80

                  ..
gi 1034554568 266 WA 267
Cdd:cd12250    81 WA 82

NURR (N-terminal unit for RNA recognition) domain found in heterogeneous nuclear ribonucleoprotein Q (hnRNPQ) and similar proteins; hnRNPQ, also termed glycine- and tyrosine-rich RNA-binding protein (GRY-RBP), or NS1-associated protein 1 (NSAP1), or Synaptotagmin-binding, cytoplasmic RNA-interacting protein (SYNCRIP), is a highly conserved RNA-binding protein that mediates the exosomal partition of a set of miRNAs. It acts as a component of the hepatocyte exosomal miRNA sorting machinery. The model corresponds to NURR domain of hnRNPQ, which has structural similarity to bacterial protein Barstar and binds to Apobec1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568  26 HTEHYKTLIEAGLPQKVAERLDEIFQTGLVAYVDLDERAIDALREFNEEGALSVLQQFKESDLSHVQNKSAFLCGVMKTY 105
Cdd:cd21066     1 HSEHFQTLLDAGLPQKVAEKLDEIYVAGLVAHSDLDERAIEALKEFNEEGALAVLQQFKDSDLSHVQNKSAFLCGVMKTY 80

                  ....*
gi 1034554568 106 RQREK 110
Cdd:cd21066    81 RQREK 85

RNA recognition motif 3 (RRM3) found in vertebrate heterogeneous nuclear ribonucleoprotein R (hnRNP R); This subgroup corresponds to the RRM3 of hnRNP R. a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches. Upon binding of RNA, hnRNP R forms oligomers, most probably dimers. hnRNP R has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP R is predominantly located in axons of motor neurons and to a much lower degree in sensory axons. In axons of motor neurons, it also functions as a cytosolic protein and interacts with wild type of survival motor neuron (SMN) proteins directly, further providing a molecular link between SMN and the spliceosome. Moreover, hnRNP R plays an important role in neural differentiation and development, as well as in retinal development and light-elicited cellular activities. hnRNP R contains an acidic auxiliary N-terminal region, followed by two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RGG motif; hnRNP R binds RNA through its RRM domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034554568 281 VKVLFVRNLATTVTEEILEKSFSEFGKLERVKKLKDYAFVHFEDRGAAVKAMDEMNGKEIEGEEIEIVLAKP 352
Cdd:cd12494     1 VKVLFVRNLATTVTEEILEKTFSQFGKLERVKKLKDYAFVHFEDRDAAVKAMDEMNGKEVEGEEIEIVLAKP 72

RNA recognition motif 2 (RRM2) found in vertebrate RNA-binding protein 46 (RBM46); This subgroup corresponds to the RRM2 of RBM46, also termed cancer/testis antigen 68 (CT68). It is a putative RNA-binding protein that shows high sequence homology with heterogeneous nuclear ribonucleoprotein R (hnRNP R) and heterogeneous nuclear ribonucleoprotein Q (hnRNP Q). Its biological function remains unclear. Like hnRNP R and hnRNP Q, RBM46 contains two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 186 NNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTVE 265
Cdd:cd12492     2 NCRLFIGAIPKEKKKEEILEEMKKVTEGVVDVIVYPSATDKTKNRGFAFVEYESHRAAAMARRKLIPGTFQLWGHTIQVD 81

                  ....
gi 1034554568 266 WADP 269
Cdd:cd12492    82 WADP 85

RNA recognition motif 3 (RRM3) found in vertebrate heterogeneous nuclear ribonucleoprotein Q (hnRNP Q); This subgroup corresponds to the RRM3 of hnRNP Q, also termed glycine- and tyrosine-rich RNA-binding protein (GRY-RBP), or NS1-associated protein 1 (NASP1), or synaptotagmin-binding, cytoplasmic RNA-interacting protein (SYNCRIP). It is a ubiquitously expressed nuclear RNA-binding protein identified as a component of the spliceosome complex, as well as a component of the apobec-1 editosome. As an alternatively spliced version of NSAP, it acts as an interaction partner of a multifunctional protein required for viral replication, and is implicated in the regulation of specific mRNA transport. hnRNP Q has also been identified as SYNCRIP that is a dual functional protein participating in both viral RNA replication and translation. As a synaptotagmin-binding protein, hnRNP Q plays a putative role in organelle-based mRNA transport along the cytoskeleton. Moreover, hnRNP Q has been found in protein complexes involved in translationally coupled mRNA turnover and mRNA splicing. It functions as a wild-type survival motor neuron (SMN)-binding protein that may participate in pre-mRNA splicing and modulate mRNA transport along microtubuli. hnRNP Q contains an acidic auxiliary N-terminal region, followed by two well defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RGG motif; hnRNP Q binds RNA through its RRM domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034554568 281 VKVLFVRNLATTVTEEILEKSFSEFGKLERVKKLKDYAFVHFEDRGAAVKAMDEMNGKEIEGEEIEIVLAKP 352
Cdd:cd12495     1 VKVLFVRNLANTVTEEILEKAFSQFGKLERVKKLKDYAFIHFDERDGAVKAMDEMNGKDLEGENIEIVFAKP 72

RNA recognition motif 2 (RRM2) found in vertebrate RNA-binding protein 47 (RBM47); This subgroup corresponds to the RRM2 of RBM47, a putative RNA-binding protein that shows high sequence homology with heterogeneous nuclear ribonucleoprotein R (hnRNP R) and heterogeneous nuclear ribonucleoprotein Q (hnRNP Q). Its biological function remains unclear. Like hnRNP R and hnRNP Q, RBM47 contains two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 185 ANNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTV 264
Cdd:cd12491     2 DNCRLFIGGIPKMKKREEILEEISKVTEGVLDVIVYASAADKMKNRGFAFVEYESHRAAAMARRKLMPGRIQLWGHQIAV 81

                          90
                  ....*....|....
gi 1034554568 265 EWADPVEEPDPEVM 278
Cdd:cd12491    82 DWAEPEIDVDEDVM 95

RNA recognition motif 2 (RRM2) found in vertebrate APOBEC-1 complementation factor (ACF); This subgroup corresponds to the RRM2 of ACF, also termed APOBEC-1-stimulating protein, 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. ACF shuttles between the cytoplasm and nucleus. ACF contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which display high affinity for an 11 nucleotide AU-rich mooring sequence 3' of the edited cytidine in apoB mRNA. All three RRMs may be required for complementation of editing activity in living cells. RRM2/3 are implicated in ACF interaction with APOBEC-1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 184 VANNRLFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNRGFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVT 263
Cdd:cd12490     1 VDNCRLFVGGIPKTKKREEILAEMKKVTDGVVDVIVYPSAADKTKNRGFAFVEYESHRAAAMARRKLLPGRIQLWGHPIA 80

                  ....*....
gi 1034554568 264 VEWADPVEE 272
Cdd:cd12490    81 VDWAEPEVE 89

RNA recognition motif 3 (RRM3) found in vertebrate RNA-binding protein 46 (RBM46); This subgroup corresponds to the RRM3 of RBM46, also termed cancer/testis antigen 68 (CT68), is a putative RNA-binding protein that shows high sequence homology with heterogeneous nuclear ribonucleoprotein R (hnRNP R) and heterogeneous nuclear ribonucleoprotein Q (hnRNP Q). Its biological function remains unclear. Like hnRNP R and hnRNP Q, RBM46 contains two well defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1034554568 281 VKVLFVRNLATTVTEEILEKSFSEF--GKLERVKKLKDYAFVHFEDRGAAVKAMDEMNGKEIEGEEIEIVLAKP 352
Cdd:cd12496     1 VKVLYVRNLMISTTEETIKAEFNKFkpGVVERVKKLRDYAFVHFFNREDAVAAMSVMNGKCIDGASIEVTLAKP 74

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 1034554568 224 DDKKKNRGFCFLEYEDHKSAAQARRRLMSgkVKVWGNVVTVEWADPVEEPDPEVMAKVKVLFVRNLATTVTEEILEKSFS 303
Cdd:TIGR01628 123 DENGKSRGYGFVHFEKEESAKAAIQKVNG--MLLNDKEVYVGRFIKKHEREAAPLKKFTNLYVKNLDPSVNEDKLRELFA 200

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034554568 304 EFGKLERVKKLKD-------YAFVHFEDRGAAVKAMDEMNGKEIEGEEIEIVLAKPPDKKRKERQAARQASR 368
Cdd:TIGR01628 201 KFGEITSAAVMKDgsgrsrgFAFVNFEKHEDAAKAVEEMNGKKIGLAKEGKKLYVGRAQKRAEREAELRRKF 272

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKD-------YAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDrdgkskgFAFVEFESPEDAEKALEALNGT 62

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERV--------KKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12316     2 LFVRNLPFTATEDELRELFEAFGKISEVhipldkqtKRSKGFAFVLFVIPEDAVKAYQELDGS 64

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 1034554568 189 LFVGSIPKNKTKENILEEFSKVTEgLVDVILYHqpDDKKKNRGFCFLEYEDHKSAAQARRRLmsGKVKVWGNVVTVE 265
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGE-VVSVRIVR--DRDGKSKGFAFVEFESPEDAEKALEAL--NGTELGGRPLKVS 72

RNA recognition motif 2 (RRM2) found in vertebrate dead end protein homolog 1 (DND1); This subgroup corresponds to the RRM2 of DND1, also termed RNA-binding motif, single-stranded-interacting protein 4. It is an RNA-binding protein that is essential for maintaining viable germ cells in vertebrates. It interacts with the 3'-untranslated region (3'-UTR) of multiple messenger RNAs (mRNAs) and prevents micro-RNA (miRNA) mediated repression of mRNA. For instance, DND1 binds cell cycle inhibitor, P27 (p27Kip1, CDKN1B), and cell cycle regulator and tumor suppressor, LATS2 (large tumor suppressor, homolog 2 of Drosophila). It helps maintain their protein expression through blocking the inhibitory function of microRNAs (miRNA) from these transcripts. DND1 may also impose another level of translational regulation to modulate expression of critical factors in embryonic stem (ES) cells. Moreover, DND1 interacts specifically with apolipoprotein B editing complex 3 (APOBEC3), a multi-functional protein inhibiting retroviral replication. The DND1-APOBEC3 interaction may play a role in maintaining viability of germ cells and for preventing germ cell tumor development. DND1 contains two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034554568 189 LFVGSIPKNKTKENILEEFSKVTEGLVDVILYHQPDDKKKNrgFCFLEYEDHKSAAQARRRLMSGKVKVWGNVVTVEWAD 268
Cdd:cd12493     5 LSVDGLPVSMDESKLLMVLQMLTDGVESVLLHPSPPKGKEV--LAVVKYSSHRAAAMAKKALVEGSRNLCGEQVTVRWLK 82

                  .
gi 1034554568 269 P 269
Cdd:cd12493    83 P 83

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034554568  188 RLFVGSIPKNKTKENILEEFSKVTEgLVDVILYHQPDdKKKNRGFCFLEYEDHKSAAQARRRLmsGKVKVWGNVVTV 264
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGK-VESVRLVRDKE-TGKSKGFAFVEFESEEDAEKALEAL--NGKELDGRPLKV 73

RNA recognition motif 2 (RRM2) found found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM2 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 a 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. Moreover, 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. 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.

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gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKL-------ERVKKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12379     5 IFIKNLDKSIDNKALYDTFSAFGNIlsckvatDENGGSKGYGFVHFETEEAAERAIEKVNGM 66

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 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKD--------YAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd21608     2 LYVGNLSWDTTEDDLRDLFSEFGEVESAKVITDretgrsrgFGFVTFSTAEAAEAAIDALNGK 64

RNA recognition motif (RRM) found in alkylated DNA repair protein alkB homolog 8 (ALKBH8) and similar proteins; This subfamily corresponds to the RRM of ALKBH8, also termed alpha-ketoglutarate-dependent dioxygenase ABH8, or S-adenosyl-L-methionine-dependent tRNA methyltransferase ABH8, expressed in various types of human cancers. It is essential in urothelial carcinoma cell survival mediated by NOX-1-dependent ROS signals. ALKBH8 has also been identified as a tRNA methyltransferase that catalyzes methylation of tRNA to yield 5-methylcarboxymethyl uridine (mcm5U) at the wobble position of the anticodon loop. Thus, ALKBH8 plays a crucial role in the DNA damage survival pathway through a distinct mechanism involving the regulation of tRNA modification. ALKBH8 localizes to the cytoplasm. It contains the characteristic AlkB domain that is composed of a tRNA methyltransferase motif, a motif homologous to the bacterial AlkB DNA/RNA repair enzyme, and a dioxygenase catalytic core domain encompassing cofactor-binding sites for iron and 2-oxoglutarate. In addition, unlike other AlkB homologs, ALKBH8 contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal S-adenosylmethionine (SAM)-dependent methyltransferase (MT) domain.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034554568 282 KVLFVRN--LATTVTEEILEKSFSEFGKLERVKKL--KDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12431     2 QHLVVANggLGNGVSREQLLEVFEKYGTVEDIVMLpgKPYSFVSFKSVEEAAKAYNALNGK 62

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKD-------YAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12380     4 VYVKNFGEDVDDDELKELFEKYGKITSAKVMKDdsgkskgFGFVNFENHEAAQKAVEELNGK 65

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1034554568 285 FVRNLATTVTEEILEKSFSEFGKLE--RVKKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12354     4 YVGNITKGLTEALLQQTFSPFGQILevRVFPDKGYAFIRFDSHEAATHAIVSVNGT 59

RNA recognition motif 2 (RRM2) found in the U1A/U2B"/SNF protein family; This subfamily corresponds to the RRM2 of U1A/U2B"/SNF protein family, containing Drosophila sex determination protein SNF and its two mammalian counterparts, U1 small nuclear ribonucleoprotein A (U1 snRNP A or U1-A or U1A) and U2 small nuclear ribonucleoprotein B" (U2 snRNP B" or U2B"), all of which consist of two RNA recognition motifs (RRMs) connected by a variable, flexible linker. SNF is an RNA-binding protein found in the U1 and U2 snRNPs of Drosophila where it is essential in sex determination and possesses a novel dual RNA binding specificity. SNF binds with high affinity to both Drosophila U1 snRNA stem-loop II (SLII) and U2 snRNA stem-loop IV (SLIV). It can also bind to poly(U) RNA tracts flanking the alternatively spliced Sex-lethal (Sxl) exon, as does Drosophila Sex-lethal protein (SXL). U1A is an RNA-binding protein associated with the U1 snRNP, a small RNA-protein complex involved in pre-mRNA splicing. U1A binds with high affinity and specificity to stem-loop II (SLII) of U1 snRNA. It is predominantly a nuclear protein that shuttles between the nucleus and the cytoplasm independently of interactions with U1 snRNA. Moreover, U1A may be involved in RNA 3'-end processing, specifically cleavage, splicing and polyadenylation, through interacting with a large number of non-snRNP proteins. U2B", initially identified to bind to stem-loop IV (SLIV) at the 3' end of U2 snRNA, is a unique protein that comprises of the U2 snRNP. Additional research indicates U2B" binds to U1 snRNA stem-loop II (SLII) as well and shows no preference for SLIV or SLII on the basis of binding affinity. U2B" does not require an auxiliary protein for binding to RNA and its nuclear transport is independent on U2 snRNA binding.

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                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1034554568 282 KVLFVRNLATTVTEEILEKSFSEF-GKLE-RVKKLKDYAFVHFEDRGAAVKAMDEMNG 337
Cdd:cd12247     3 KILFLQNLPEETTKEMLEMLFNQFpGFKEvRLVPRRGIAFVEFETEEQATVALQALQG 60

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

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                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12609     3 IFVGNVSATCTSDELRGLFEEFGRVVECDKVKDYAFVHMEREEEALAAIEALNGK 57

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.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1034554568 293 VTEEILEKSFSEFGKLERV--KKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12305    14 ITEDVLKKAFSPFGNIINIsmEIEKNCAFVTFEKMESADQAIAELNGT 61

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKL-----------KDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12355     2 LWIGNLDPRLTEYHLLKLLSKYGKIKKFDFLfhktgplkgqpRGYCFVTFETKEEAEKAIECLNGK 67

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVK-------KLKDYAFVHFEDRGAAVKAMDEMNG 337
Cdd:TIGR01628  91 IFVKNLDKSVDNKALFDTFSKFGNILSCKvatdengKSRGYGFVHFEKEESAKAAIQKVNG 151

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

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                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKDYAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12343     2 IFVGNLPDAATSEELRALFEKYGKVTECDIVKNYAFVHMEKEEDAEDAIKALNGY 56

RNA recognition motif 1 (RRM1) found in Saccharomyces cerevisiae protein PES4, protein MIP6 and similar proteins; The family includes PES4 (also called DNA polymerase epsilon suppressor 4) and MIP6 (also called MEX67-interacting protein 6), both of which are predicted RNA binding proteins that may act as regulators of late translation, protection, and mRNA localization. MIP6 acts as a novel factor for nuclear mRNA export, binds to both poly(A)+ RNA and nuclear pores. It interacts with MEX67. Members in this family contain four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the first RRM motif.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKD--------YAFVHFEDRGAAVKAMDEMN 336
Cdd:cd21601     3 LFIGDLDKDVTEEMLRDIFSKYKSLVSVKICLDsetkkslgYGYLNFSDKEDAEKAIEEFN 63

RNA recognition motif 3 (RRM3) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM3 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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1034554568 282 KVLFVRNLATTVTEEILEKSFSEFGKLERVKKLKDY--------AFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12415     1 KTVFIRNLSFDTTEEDLKEFFSKFGEVKYARIVLDKdtghskgtAFVQFKTKESADKCIEAANDE 65

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLER---VK-----KLKDYAFVHFEDRGAAVKAMDEMNGKEIEGEEIEIVLAKP 352
Cdd:cd12413     2 LFVRNLPYDTTDEQLEELFSDVGPVKRcfvVKdkgkdKCRGFGYVTFALAEDAQRALEEVKGKKFGGRKIKVELAKK 78

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

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                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVK--------KLKDYAFVHFEDRGAAVKAM 332
Cdd:cd12397     1 LFVGNLSFETTEEDLRKHFAPAGKIRKVRmatfedsgKCKGFAFVDFKEIESATNAV 57

RNA recognition motif (RRM) found in cold inducible RNA binding protein (CIRBP), RNA binding motif protein 3 (RBM3) and similar proteins; This subfamily corresponds to the RRM domain of two structurally related heterogenous nuclear ribonucleoproteins, CIRBP (also termed CIRP or A18 hnRNP) and RBM3 (also termed RNPL), both of which belong to a highly conserved cold shock proteins family. The cold shock proteins can be induced after exposure to a moderate cold-shock and other cellular stresses such as UV radiation and hypoxia. CIRBP and RBM3 may function in posttranscriptional regulation of gene expression by binding to different transcripts, thus allowing the cell to response rapidly to environmental signals. However, the kinetics and degree of cold induction are different between CIRBP and RBM3. Tissue distribution of their expression is different. CIRBP and RBM3 may be differentially regulated under physiological and stress conditions and may play distinct roles in cold responses of cells. CIRBP, also termed glycine-rich RNA-binding protein CIRP, is localized in the nucleus and mediates the cold-induced suppression of cell cycle progression. CIRBP also binds DNA and possibly serves as a chaperone that assists in the folding/unfolding, assembly/disassembly and transport of various proteins. RBM3 may enhance global protein synthesis and the formation of active polysomes while reducing the levels of ribonucleoprotein complexes containing microRNAs. RBM3 may also serve to prevent the loss of muscle mass by its ability to decrease cell death. Furthermore, RBM3 may be essential for cell proliferation and mitosis. Both, CIRBP and RBM3, contain an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), that is involved in RNA binding, and C-terminal glycine-rich domain (RGG motif) that probably enhances RNA-binding via protein-protein and/or protein-RNA interactions. Like CIRBP, RBM3 can also bind to both RNA and DNA via its RRM domain.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1034554568 284 LFVRNLATTVTEEILEKSFSEFGKLERVKKLKD--------YAFVHFEDRGAAVKAMDEMNGK 338
Cdd:cd12449     3 LFVGGLSFDTNEQSLEEVFSKYGQISEVVVVKDretqrsrgFGFVTFENPDDAKDAMMAMNGK 65