We have analyzed how single-strand DNA gaps affect DNA replication in Xenopus egg extracts. DNA lesions generated by etoposide, a DNA topoisomerase II inhibitor, or by exonuclease treatment activate a DNA damage checkpoint that blocks initiation of plasmid and chromosomal DNA replication. The checkpoint is abrogated by caffeine and requires ATR, but not ATM, protein kinase. The block to DNA synthesis is due to inhibition of Cdc7/Dbf4 protein kinase activity and the subsequent failure of Cdc45 to bind to chromatin. The checkpoint does not require pre-RC assembly but requires loading of the single-strand binding protein, RPA, on chromatin. This is the biochemical demonstration of a DNA damage checkpoint that targets Cdc7/Dbf4 protein kinase.
An ATR- and Cdc7-dependent DNA damage checkpoint that inhibits initiation of DNA replication / Costanzo, Vincenzo; D., Shechter; P. J., Lupardus; K. A., Cimprich; M., Gottesman; J., Gautier. - In: MOLECULAR CELL. - ISSN 1097-2765. - STAMPA. - 11:(2003), pp. 203-213.
An ATR- and Cdc7-dependent DNA damage checkpoint that inhibits initiation of DNA replication.
COSTANZO, VINCENZO;
2003
Abstract
We have analyzed how single-strand DNA gaps affect DNA replication in Xenopus egg extracts. DNA lesions generated by etoposide, a DNA topoisomerase II inhibitor, or by exonuclease treatment activate a DNA damage checkpoint that blocks initiation of plasmid and chromosomal DNA replication. The checkpoint is abrogated by caffeine and requires ATR, but not ATM, protein kinase. The block to DNA synthesis is due to inhibition of Cdc7/Dbf4 protein kinase activity and the subsequent failure of Cdc45 to bind to chromatin. The checkpoint does not require pre-RC assembly but requires loading of the single-strand binding protein, RPA, on chromatin. This is the biochemical demonstration of a DNA damage checkpoint that targets Cdc7/Dbf4 protein kinase.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.