Cell-cycle signaling: Atm displays its many talents.
The discovery of multiple signaling cascades downstream of Atm may lead to a clearer understanding of the diverse defects seen in ataxia-telangiectasia. These pathways - which include evolutionarily conserved Chk1 and Atr, and non-conserved p21, p53 and AbI - guard genomic integrity after DNA damage.
Westphal CH