Translation Control

Nck-1 Couples Insulin to Translation Control

Science's STKE  23 Apr 2002:
Vol. 2002, Issue 129, pp. tw154
DOI: 10.1126/stke.2002.129.tw154


Nck-1 is a scaffolding protein thought to link substrate proteins to the insulin receptor. Kebache et al. conducted a yeast two-hybrid screen for proteins that interacted with the SH3 (Src-homology 3) domains of Nck-1 and turned up eukayotic initiation factor 2 (eIF2β). Like eIF2α, which is regulated by phosphorylation, eIF2β takes part in the initiation of translation, but regulation of eIF2β had not been described. Nck-1 and eIF2β were immunoprecipitated together to form ribosome-enriched preparations from human cell lines; treatment of cells with insulin enhanced the association of Nck-1 with ribosomal subunits. Overexpression of Nck-1 enhanced both Cap-dependent and Cap-independent translation through IRES (internal ribosome entry site) elements. Thus, Nck appears to have roles both early in insulin signaling at the receptor and further downstream in control of protein complexes that initiate translation.

S. Kebache, D. Zuo, E. Chevet, L. Larose, Modulation of protein translation by Nck-1. Proc. Natl. Acad. Sci. U.S.A. 99, 5406 -5411 (2002). [Full Text] [Abstract]