RNA recognition motif (RRM) found in vertebrate Ewing Sarcoma Protein (EWS)
This subgroup corresponds to the RRM of EWS, also termed Ewing sarcoma breakpoint region 1 protein, a member of the FET (previously TET) (FUS/TLS, EWS, TAF15) family of RNA- and DNA-binding proteins whose expression is altered in cancer. It is a multifunctional protein and may play roles in transcription and RNA processing. EWS is involved in transcriptional regulation by interacting with the preinitiation complex TFIID and the RNA polymerase II (RNAPII) complexes. It is also associated with splicing factors, such as the U1 snRNP protein U1C, suggesting its implication in pre-mRNA splicing. Additionally, EWS has been shown to regulate DNA damage-induced alternative splicing (AS). Like other members in the FET family, EWS contains an N-terminal Ser, Gly, Gln and Tyr-rich region composed of multiple copies of a degenerate hexapeptide repeat motif. The C-terminal region consists of a conserved nuclear import and retention signal (C-NLS), a C2/C2 zinc-finger motif, a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and at least 1 arginine-glycine-glycine (RGG)-repeat region. EWS specifically binds to poly G and poly U RNA. It also binds to the proximal-element DNA of the macrophage-specific promoter of the CSF-1 receptor gene.