University of Dundee

EASTBIO: Trimming the fat –identification of de-S-acylating enzymes from plants

This 4 year PhD project is part of a competition funded by EASTBIO BBSRC Doctoral Training Partnership This opportunity is open to UK and EU nationals.

Applicants should apply by completing the EASTBIO application form (downloadable from the EASTBIO website) and e-mail to Candidates should also include their academic transcripts and ensure that they ask their referees to send completed references to Applicants may wish to explain their motivation for joining the EASTBIO training programme.

Plants must alter their cellular processes and functions in response to a stimulus, such as hormones or pathogens, and all of this relies upon the action of proteins. Proteins themselves are regulated by a complex interaction of post-translational modifications that control protein activity, interactions, turnover and localisation within the cell. We have found that one post-translational modification, S-acylation, affects every aspect of plant growth and development and is critical for life.S-acylation is a fatty acid based post-translational modification of proteins and it has been suggested that ~50% of plant membrane proteins are modified by S-acylation making it a major factor in how membrane associated processes occur and are regulated. However, S-acylation was only recently discovered so many aspects of its function and regulation have yet to be uncovered. S-acylation is also reversible, in a similar manner to phosphorylation or ubiquitination, and is now emerging as a key regulator of cellular function. Despite this obvious importance and knowledge of proteins that undergo reversible S-acylation we do not yet know how S-acyl groups are removed from plant proteins making understanding of the regulatory cycle impossible.

To resolve this issue we recently performed a proteomics based screen and identified a range of novel enzyme activities potentially able to act as de-S-acylating enzymes. The aim of this project is to determine which of these enzymes are true de-S-acylating enzymes by characterising their activities in vivo and in vitro. You will subsequently characterise the role of these enzymes in plants using biochemical, molecular and genetic approaches.Skills to be acquired include: Proteomics, activity based protein profiling, protein expression, S-acylation assays, enzyme/proteinbiochemistry, molecular biology, plant transformation and genetics.

The University of Dundee is currently #1 for Life Sciences research in the UK. The Division of Plant Sciences is located at the Scottish Govt. James Hutton agricultural research institute. This provides expertise and links to world class crop and applied plant sciences and enables us to deliver solutions to global issues such as food/nutritional security, climate change, biofuels and water security. The University of Dundee is ranked 4thin the UK for student experience and satisfaction.

General review of S-acylation in plants: Turnbull and Hemsley (2017) Curr Opin Plant Biol. 40:63-70. doi: 10.1016/j.pbi.2017.07.007.

Strategy used to identify de-S-acylating enzymes: Martin et al (2011) Nature Methods 9:84–89. doi: 10.1038/nmeth.1769

Potential strategy to characterise de-S-acylating enzymes: Lin and Connibear (2015) eLife 4:e11306. doi: 10.7554/eLife.11306.