Chaudhary , N. and Nakka , K.K. and Chavali , P.L. and Bhat , J. and Chatterjee , S. and Chattopadhyay, S. (2014) SMAR1 coordinates HDAC6-induced deacetylation of Ku70 and dictates cell fate upon irradiation. Cell Death and Disease , 5. e1447-e1447.

Text 15. Dr. Mitra (Cell Death & Dieases.) paid Open Access.pdf Restricted to Repository staff only Download (509Kb) | Request a copy

Abstract

Acetylation status of DNA end joining protein Ku70 dictates its function in DNA repair and Bax-mediated apoptosis. Despite the knowledge of HDACs and HATs that are reported to modulate the acetylation dynamics of Ku70, very little is known about proteins that critically coordinate these key modifications. Here, we demonstrate that nuclear matrix-associated protein scaffold/matrixassociated region-binding protein 1 (SMAR1) is a novel interacting partner of Ku70 and coordinates with HDAC6 to maintain Ku70 in a deacetylated state. Our studies revealed that knockdown of SMAR1 results in enhanced acetylation of Ku70, which leads to impaired recruitment of Ku70 in the chromatin fractions. Interestingly, ionizing radiation (IR) induces the expression of SMAR1 and its redistribution as distinct nuclear foci upon ATM-mediated phosphorylation at serine 370. Furthermore, SMAR1 regulates IR-induced G2/M cell cycle arrest by facilitating Chk2 phosphorylation. Alternatively, SMAR1 provides radioresistance by modulating the association of deacetylated Ku70 with Bax, abrogating the mitochondrial translocation of Bax. Thus, we provide mechanistic insights of SMAR1-mediated regulation of repair and apoptosis via a complex crosstalk involving Ku70, HDAC6 and Bax. Cell Death and Disease (2014) 5, e1447; doi:10.1038/cddis.2014.397; published online 9 October 2014

Item Type:	Article
Additional Information:	This is Open Access Journal (for full text click above weblink)
Subjects:	Cancer Biology
Depositing User:	Mr. Rameshwar Nema
Date Deposited:	28 Apr 2015 12:03
Last Modified:	18 Dec 2021 13:27
URI:	http://nccs.sciencecentral.in/id/eprint/159

Actions (login required)

View Item