LIM Protein Ajuba Participates in the Repression of the ATR-Mediated DNA Damage Response

Authors

Sampada Kalan, CUNY Hunter College
Anastasiya Matveyenko, CUNY Hunter College
Diego Loayza, CUNY Hunter CollegeFollow

Document Type

Article

Publication Date

May 2013

Abstract

LIM proteins constitute a superfamily characterized by the presence of a LIM domain, known to be involved in protein–protein interactions. Our previous work has implicated members of the Zyxin family of LIM proteins, namely TRIP6 and LPP, in the repression of the DNA damage response (DDR) at telomeres. Here, we describe a role for Ajuba, a closely related LIM molecule, in repressing the ATR-mediated DDR. We found that depletion of Ajuba led to apparent delays in the cell cycle, accompanied with increased Rb phosphorylation, Chk1 phosphorylation, induction of p53, and cell death. Ajuba could be found in a complex with replication protein A (RPA), and its depletion led to RPA phosphorylation, known to be an early event in ATR activation. We propose that Ajuba protects against unscheduled ATR signaling by preventing inappropriate RPA phosphorylation.

Comments

This work was originally published in Frontiers in Genetics, available at doi:10.3389/fgene.2013.00095.