Arginylated Calreticulin at Plasma Membrane Increases Susceptibility of Cells to Apoptosis

AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC

Lugar: Baltimore; Año: 2012 vol. 287 p. 22043 - 22043

ost-translational modifications of proteins are important forthe regulation of cell fate and functions; one of these post-translationalmodifications is arginylation.Wehave previously establishedthat calreticulin (CRT), an endoplasmic reticulum resident,is also one of the arginylated substrates found in thecytoplasm. In the present study, we describe that arginylatedCRT (R-CRT) binds to the cell membrane and identified its roleas a preapoptotic signal.Wealso show that cells lacking arginyltRNAprotein transferase are less susceptible to apoptosis thanwild type cells. Under these conditions R-CRT is present on thecell membrane but at early stages is differently localized in stressgranules. Moreover, cells induced to undergo apoptosis byarsenite show increased R-CRT on their cell surface. Exogenouslyapplied R-CRT binds to the cell membrane and is able toboth increase the number of cells undergoing apoptosi