Calreticulin-dimerization Induced by Post-translational Arginylationis is Critical for Stress Granules Scaffolding

PERGAMON-ELSEVIER SCIENCE LTD

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

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 angiogenesisbut the molecular effects of proteins arginylated in vivo are largely unknown. In the present study, wedemonstrate that arginylation reduces CRT (calreticulin) thermostability and induces a greater degree ofdimerization and oligomerization. R-CRT (arginylated calreticulin) forms disulfide-bridged dimers thatare increased in low Ca2+conditions at physiological temperatures, a similar condition to the cellularenvironment 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 shocktreatment where R-CRT is the only isoespecies of CRT that associates in