Calreticulin-Dimerization Induced by Post-Translational Arginylation is Critical for Stress Granules Scaffolding

CARPIO M.A.; DECCA M.B.; LÓPEZ SAMBROOKS C.; DURAND E.S.; MONTICH G.G.; HALLAK M.E.

INTERNATIONAL JOURNAL OF BIOCHEMISTRY AND CELLULAR BIOLOGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2013 vol. 45 p. 1223 - 1223

1357-2725

rotein arginylation mediated by arginyl-tRNA protein transferase is a post-translational modificationthat occurs widely in biology, it has been shown to regulate protein and properties and functions. Post-translational arginylation is critical for embryogenesis, cardiovascular development and angiogenesis but the molecular effects of proteins arginylated in vivo are largely unknown. In the present study, we demonstrate that arginylation reduces CRT (calreticulin) thermostability and induces a greater degree of dimerization and oligomerization. R-CRT (arginylated calreticulin) forms disulfide-bridged dimers that are increased in low Ca2+ conditions at physiological temperatures, a similar condition to the cellular environment that it required for arginylation of CRT. Moreover, R-CRT self-oligomerizes through non-covalent interactions that are enhanced at temperatures above 40◦C, condition that mimics the heat shock treatment where R-CRT is the only isoespecies of CRT that associa