Identification and characterization of human Mex-3 proteins, a novel family of evolutionarily conserved RNA-binding proteins differentially localized to processing bodies.

In 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.
Mesh Terms:
Active Transport, Cell Nucleus, Amino Acid Sequence, Animals, Caenorhabditis elegans Proteins, Cell Line, Cell Nucleus, Conserved Sequence, Cytoplasmic Structures, Evolution, Molecular, Humans, Molecular Sequence Data, Multigene Family, Phosphoproteins, RNA Processing, Post-Transcriptional, RNA-Binding Proteins, RNA-Induced Silencing Complex, Sequence Homology, Amino Acid, Tissue Distribution
Nucleic Acids Res.
Date: Feb. 03, 2007
Download Curated Data For This Publication
143531
Switch View:
  • Interactions 2