Phosphorylation by ATM and ATR at T847, S327
Phosphorylation at S327 by ATM and ATR are essential for shift from A_NHEJ to HR
Phosphorylation by CDC2(CDK1) in cell cycle dep manner to shift from C_NHEJ ot HR at: Ser 267
This phosphorylation allows resection that initiates HR and blocks binding of Ku70/Ku80 complex that initiates C_NHEJ.
PMID:19357644, PMID:15485915, PMID:19490890, PMID:18716619 (for CDK-dep phosph), PMID:20051983
BRCA1 and CtIP interactions make shift from A_NHEJ and C_NHEJ toward HR
Resected DNA in HR is a positive trigger for amplification of the HR pathway (positive loop):
Only when CDKs are fully active, this fully activates HR during S and G2 phases: