9406050 Baker CP1 (encoded by the gene CEP1) is a moderately abundant, sequence-specific DNA-binding protein of S. cerevisiae. A member of the general regulatory factor family of yeast chromosomal proteins, CP1 is multifunctional; it performs roles in chromosome segregation and in regulating gene expression. It is believed that CP1 acts primarily as a local organizer of chromatin structure, configuring the DNA into conformations conducive to the assembly of kinetochores and active transcription complexes. To learn more about CP1 action, a synthetic lethal genetic analysis of CP1 is being undertaken. Mutations synthetically lethal with cep1 will be isolated and complementation groups defined. The cep1 synthetic lethal mutations (csl's) will be classified by phenotype; the mutants will be tested for defects in mitotic and meiotic chromosome segregation, defects in transcription, synergistic interaction between the csl and a cis-acting centromere mutation, perturbations in cell cycle progression, and ability to be rescued by partially-active mutant alleles of cep1. Wild-type genes corresponding to the most interesting csl alleles will be isolated from yeast genomic plasmid libraries and characterized. %%% The long term goal of this research is to provide general insights into the biochemical mechanisms that establish eukaryotic chromosome structure and effect changes in that structure to meet functional needs. Chromosome structure is an essential element in both the regulation of gene expression and the proper distribution of chromosomes at cell division. ***
