RNA-binding motif protein 8 (IPR008111)

Short name: RNA-bd_8

Overlapping homologous superfamilies

Family relationships



RNA-binding motif protein 8 (RBM8) contains a putative RNA-binding domain known as an RNA recognition motif (RRM). The RRM motif is found in numerous RNA-binding proteins, including heterogenous nuclear ribonucleoproteins (hnRNPs), and proteins implicated in regulation of alternative splicing. The RRM is a 90-residue domain that binds single-stranded RNA; the structure consists of four beta-stands and two alpha-helices arranged in an alpha/beta sandwich, with a third helix present in some cases during RNA binding [PMID: 8290338]. Three-dimensional modelling of the RBM8 RRM domain indicates that the sequences fold into an RNA-binding domain, forming a hydrophobic core between a beta-sheet and two helices.

The human RBM8A protein is ubiquitously expressed; the protein is localised predominantly in the cell nucleus and diffused throughout the cytoplasm [PMID: 11013075]. It preferentially associates with mRNAs produced by splicing, including both nuclear mRNAs and newly exported cytoplasmic mRNAs. Evidence suggests the protein remains associated with spliced mRNAs as a tag to indicate the position of spliced introns. Human RBM8A protein specicially binds to MAGOH, the human homologue of Drosophila mago nashi, a protein required for normal germ plasm development in the Drosophila embryo [PMID: 10662555]; a similar association occurs with the Drosophila RBM8 protein, Tsunagi [PMID: 11691839].

The RBM8A and RBM8B protein sequences contain a putative bipartate nuclear localisation signal [PMID: 1991323] at the N terminus, as well a stretch of glycine residues. In addition, the RRM contained within RBM8A and RBM8B contains one set of the two consensus nucleic acid-binding motifs, RNP-1 and RNP-2, characteristic of heterogeneous nuclear ribonucleoprotein (hnRNP).

GO terms

Biological Process

GO:0006396 RNA processing

Molecular Function

GO:0003723 RNA binding

Cellular Component

GO:0005737 cytoplasm
GO:0005634 nucleus

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.