Is PER3 required for CHK2 activation in human cells?
['Per3, a circadian gene, is required for Chk2 activation in human cells.', 'Depletion of Per3 by siRNA almost completely abolished activation of checkpoint kinase 2 (Chk2) after inducing DNA damage in human cells.', 'Per3 overexpression induced Chk2 activation in the absence of exogenous DNA damage,', 'Per3 overexpression also led to the inhibition of cell proliferation and apoptotic cell death.', 'These combined results suggest that Per3 is a checkpoint protein that plays important roles in checkpoint activation, cell proliferation and apoptosis.', 'Depletion of Per3 by siRNA almost completely abolished activation of checkpoint kinase 2 (Chk2) after inducing DNA damage in human cells', 'Per3 overexpression induced Chk2 activation in the absence of exogenous DNA damage, and this activation depended on ATM', 'In addition, Per3 physically interacted with ATM and Chk2']
['Depletion of Per3 by siRNA almost completely abolished activation of checkpoint kinase 2 (Chk2) after inducing DNA damage in human cells.Per3, a circadian gene, is required for Chk2 activation in human cells.', 'Per3, a circadian gene, is required for Chk2 activation in human cells.  ', 'Per3, a circadian gene, is required for Chk2 activation in human cells.Per3 overexpression induced Chk2 activation in the absence of exogenous DNA damage,', 'Per3 gene, involved in circadian rhythm control, is required for Chk2 activation in human cells.']
['yes']