※ RAD53 family introduction

    RAD53, also known as Checkpoint kinase 2, is a key kinase which is required in checkpoint-mediated cell cycle related processes. When damage response occurred, Mec1 protein is recruited to bind DNA and triggers the downstream signal cascade. Rad9 is activated via phosphorylation by Mec1 and as a result RAD53 binds to Rad9 with the phospho-binding domain FHA and undergo autophosphorylation events which are important on activation of Rad53. Activated RAD53 amplifies the original signals and triggers the downstream events of checkpoint activation, including cell cycle delay, DNA repair, replication fork stabilization and fork restart processes (1).

Reference
1. Branzei, D. and Foiani, M. (2006) The Rad53 signal transduction pathway: Replication fork stabilization, DNA repair, and adaptation. Exp Cell Res, 312, 2654-2659. PMID: 16859682