ATR Proteins and Enzymes

Ataxia Telangiectasia Mutated (ATM) and Rad3- related (ATR) protein is a member of the phosphatidyl-inositol 3-kinase (PI 3-kinase) like family of protein kinases. ATR has a predicted molecular mass of approximately 301 kDa, and it has been shown to be involved in cellular responses to DNA damage. Specifically, it plays a role in checkpoint activation in response to either the presence of stalled replication forks, or by the presence of lesions caused by UV light. Inactivation of ATR is an embryonic lethal event in mice.