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).

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gi 354548852  47 TSLFACSVHEAVFEAREQKER 67
Cdd:cd12710    1 TALFACSVHEAVFEDQEQRER 21

RNA recognition motif (RRM) found in vertebrate regulator of calcineurin 3 (RCAN3); This subgroup corresponds to the RRM of RCAN3, also termed calcipressin-3, or Down syndrome candidate region 1-like protein 2 (DSCR1L2), or myocyte-enriched calcineurin-interacting protein 3 (MCIP3), encoded by a ubiquitously expressed DSCR1L2 gene. Overexpressed RCAN3 binds and inhibits the Ca2+/calmodulin-dependent phosphatase calcineurin (also termed PP2B or PP3C), and further down-regulates nuclear factor of activated T cells (NFAT)-dependent cytokine gene expression in activated human Jurkat T cells. Moreover, RCAN3 interacts with cardiac troponin I (TNNI3), a heart-specific inhibitory subunit of the troponin complex, and may play a role in cardiac contraction. RCAN3 consists of an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a highly conserved SP repeat domain containing the phosphorylation site by GSK-3, a well-known PxIxIT motif responsible for docking many substrates to calcineurin, and an unrecognized C-terminal TxxP motif of unknown function.

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gi 354548852  47 TSLFACSVHEAVFEAREQKER 67
Cdd:cd12710    1 TALFACSVHEAVFEDQEQRER 21

RNA recognition motif (RRM) found in vertebrate regulator of calcineurin 3 (RCAN3); This subgroup corresponds to the RRM of RCAN3, also termed calcipressin-3, or Down syndrome candidate region 1-like protein 2 (DSCR1L2), or myocyte-enriched calcineurin-interacting protein 3 (MCIP3), encoded by a ubiquitously expressed DSCR1L2 gene. Overexpressed RCAN3 binds and inhibits the Ca2+/calmodulin-dependent phosphatase calcineurin (also termed PP2B or PP3C), and further down-regulates nuclear factor of activated T cells (NFAT)-dependent cytokine gene expression in activated human Jurkat T cells. Moreover, RCAN3 interacts with cardiac troponin I (TNNI3), a heart-specific inhibitory subunit of the troponin complex, and may play a role in cardiac contraction. RCAN3 consists of an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a highly conserved SP repeat domain containing the phosphorylation site by GSK-3, a well-known PxIxIT motif responsible for docking many substrates to calcineurin, and an unrecognized C-terminal TxxP motif of unknown function.

                         10        20
                 ....*....|....*....|.
gi 354548852  47 TSLFACSVHEAVFEAREQKER 67
Cdd:cd12710    1 TALFACSVHEAVFEDQEQRER 21