Identification and characterization of human Mex-3 proteins, a novel family of evolutionarily conserved RNA-binding proteins differentially localized to processing bodies
2007; Oxford University Press; Volume: 35; Issue: 4 Linguagem: Inglês
10.1093/nar/gkm016
ISSN1362-4962
AutoresKarine Buchet-Poyau, Julien Courchet, Hervé Le Hir, Bertrand Séraphin, Jean‐Yves Scoazec, Laurent Duret, Claire Domon‐Dell, Jean‐Noël Freund, Marc Billaud,
Tópico(s)Genetics, Aging, and Longevity in Model Organisms
ResumoIn Caenorhabditis elegans, the Mex-3 protein is a translational regulator that specifies the posterior blastomere identity in the early embryo and contributes to the maintenance of the germline totipotency. We have now identified a family of four homologous human Mex-3 genes, called hMex-3A to -3D that encode proteins containing two heterogeneous nuclear ribonucleoprotein K homology (KH) domains and one carboxy-terminal RING finger module. The hMex-3 are phosphoproteins that bind RNA through their KH domains and shuttle between the nucleus and the cytoplasm via the CRM1-dependent export pathway. Our analysis further revealed that hMex-3A and hMex-3B, but not hMex-3C, colocalize with both the hDcp1a decapping factor and Argonaute (Ago) proteins in processing bodies (P bodies), recently characterized as centers of mRNA turnover. Taken together, these findings indicate that hMex-3 proteins constitute a novel family of evolutionarily conserved RNA-binding proteins, differentially recruited to P bodies and potentially involved in post-transcriptional regulatory mechanisms.
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