Analysis of the Fission Yeast Checkpoint Rad Proteins

DNA damage invokes a wide range of cellular responses, including delays to S phase and mitosis andchanges in transcriptional profile (Elledge 1996). In yeastmodel systems, the delay to S-phase progression (intra-Sphase checkpoint), the delay to mitosis (G2-M damagecheckpoint), and many of the transcriptional responses aredependent on a defined set of checkpoint proteins. In addition, growing genetic evidence suggests a role forcheckpoint proteins in controlling specific DNA repair responses, particularly within S phase (Murray et al. 1997;Paulovich et al. 1997). Relatively little is known aboutspecific mechanisms of DNA repair during S phase...