ANALYSIS OF A HISTONE H2A VARIANT FROM FISSION YEAST - EVIDENCE FOR AROLE IN CHROMOSOME STABILITY

We have isolated and characterised the pht1 gene from the fission yeas t Schizosaccharomyces pombe. The sequence of the predicted translation product has revealed a striking similarity to the family of H2A.F/Z h istone variant proteins, which have been found in a variety of differe nt organisms. Cells deleted for the pht1 gene locus grow slowly, exhib it an altered colony morphology, increased resistance to heat shock an d show a significant decrease in the fidelity of segregation of an S. pombe minichromosome. We propose that the histone H2A variant encoded by the pht1 gene is important for chromosomal structure and function, possibly including a role in controlling the fidelity of chromosomal s egregation during mitosis.