Characterisation of histone deacetylase-dependent transcriptional repression by the transcription factor Hac1

A self-funded PhD studentship is available in the group of Dr. Martin Schröder in the Department of Biosciences at Durham University to study stress signalling mechanisms originating from the endoplasmic reticulum.

Endoplasmic reticulum (ER) stress contributes to the development and progression of many diverse diseases affecting secretory tissues, such as diabetes and neurodegenerative diseases. The successful candidate will employ modern genetic and molecular techniques to understand the underlying cell biological mechanisms that integrate physiologic events in the endoplasmic reticulum into wider cellular physiology and control of cellular differentiation programmes.

Accumulation of unfolded proteins in the endoplasmic reticulum activates the bifunctional transmembrane spanning protein kinase-endoribonuclease Ire1. Ire1 transduces the ER stress signal by initiating an unconventional splicing event in the mRNA coding for the transcription factor Hac1ⁱ. Hac1ⁱ directly activates expression of many ER stress-responsive genes by binding to unfolded protein response elements in their promoters, but also controls transcriptional regulation of early meiotic genes and meiotic development by the Rpd3-Sin3 histone deacetylase through less well understood mechanisms [1, 2]. In this project, you will employ genetic and molecular experimentation in the eukaryotic model organism budding yeast (Saccharomyces cerevisiae) to characterise how Hac1ⁱ integrates the ER stress signal into control of the Rpd3-Sin histone deacetylase, expression of early meiotic genes, and ultimately meiotic development.

You will specifically address whether Hac1ⁱ modulates the subunit composition of the Rpd3-Sin3 HDAC to enhance transcriptional repression by this HDAC. You will evaluate the hypothesis that Hac1ⁱ induces transcription of a gene or genes coding for a subunit of the Rpd3-Sin3 HDAC. The successful candidate will use a series of yeast strains deleted for individual subunits of the Rpd3-Sin3 HDAC to systematically identify genes coding for subunits of the HDAC whose deletion abolishes function of the HDAC as well as genes coding for subunits whose deletion abolishes responsiveness of the HDAC to Hac1ⁱ.

To address these aims, the student will be trained and use a range of molecular biology techniques, such as cloning, PCR, yeast strain construction, β-galactosidase reporter assays, Northern blotting, quantitative reverse transcriptase PCR, Western blotting, and chromatin immunoprecipitation.

Applicants should possess at least a 2:1 Honours degree, or equivalent, in an appropriate subject (e.g. biochemistry, cell biology, molecular biology, or genetics).