| Using Saccharomyces cerevisiae, our lab has previously demonstrated that particular histone H2A tail residues are required for the induction of a number of stress response pathways. Focusing on heat stress, this work demonstrates that individual H2A tat residues S122 and T126 play a significant rote in survival of prolonged heat shock, while S122 and K127 are important for the acquisition of thermotolerance. Strains bearing deletions of either of the H2A tails (hta1-DeltaC and hta1-DeltaN ) demonstrate severe heat sensitive and thermointolerant phenotypes. To determine the cause of the observed phenotypes we analyzed the expression of a number of heat shock genes that are rapidly expressed in response to heat shock (HSP26, HSP70, HSP82, and HSP104) using either northern blot or rtRT-PCR. Our results suggest that white H2A residues are crucial for heat stress response and thermotolerance, this is not due to transcriptional defects for the suite of HSP genes tested. |
