PT  - JOURNAL ARTICLE
AU  - Wang, Bin
AU  - Matsuoka, Shuhei
AU  - Carpenter, Phillip B.
AU  - Elledge, Stephen J.
TI  - 53BP1, a Mediator of the DNA Damage Checkpoint
AID  - 10.1126/science.1076182
DP  - 2002 Nov 15
TA  - Science
PG  - 1435--1438
VI  - 298
IP  - 5597
4099  - http://science.sciencemag.org/content/298/5597/1435.short
4100  - http://science.sciencemag.org/content/298/5597/1435.full
SO  - Science2002 Nov 15; 298
AB  - 53BP1 binds to the tumor suppressor protein p53 and has a potential role in DNA damage responses. We used small interfering RNA (siRNA) directed against 53BP1 in mammalian cells to demonstrate that 53BP1 is a key transducer of the DNA damage checkpoint signal. 53BP1 was required for p53 accumulation, G2-M checkpoint arrest, and the intra-S-phase checkpoint in response to ionizing radiation. 53BP1 played a partially redundant role in phosphorylation of the downstream checkpoint effector proteins Brca1 and Chk2 but was required for the formation of Brca1 foci in a hierarchical branched pathway for the recruitment of repair and signaling proteins to sites of DNA damage.