The role of the Dgk1 and Pah1 in lipid interconversion on saccharomyces cerevisiae vacuole physiology, homeostasis, protein sorting and fusion

Stoy, Colin

Permalink

https://hdl.handle.net/2142/50420 Copy

Description

Title

The role of the Dgk1 and Pah1 in lipid interconversion on saccharomyces cerevisiae vacuole physiology, homeostasis, protein sorting and fusion

Author(s)

Stoy, Colin

Issue Date

2014-09-16

Director of Research (if dissertation) or Advisor (if thesis)

Fratti, Rutilio A.

Department of Study

School of Integrative Biology

Discipline

Biology

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Diacylglycerol
• Diacylglycerol Kinase
• Phosphatidic Acid
• Phosphatidic Acid Phosphatase
• Saccharomyces Cerevisiae
• Vacuole Fusion
• Vacuole Homeostasis
• Protein Sorting
• Lipid Interconversion

Abstract

A variety of factors are needed for the homotypic fusion of the yeast vacuole, including a number of proteins and regulatory lipids. The deletion of the phosphatidic acid (PA) phosphatase gene Pah1, which converts PA in diacylglycerol kinase (DAG), was previously shown to produce a fragmented vacuole phenotype, greatly inhibit fusion and result in the vacuolar protein sorting defect. As such, the impact of the deletion of the complementary DAG kinase gene Dgk1, which converts DAG into PA, and the impact of deleting both genes was observed. The deletion of Dgk1 was observed to augment fusion, despite showing a moderately fragmented vacuolar phenotype. This fusion was shown to still be dependent on the core fusion machinery proteins, and resistant to inhibition by the DAG ligand C1B, and was better able to maintain fusion capacity when held for an extended time on ice. This deletion also had a unique protein profile, different from the wild type background, but not the inverse of the Pah1 deletion. The double deletion showed highly fragmented vacuoles, much like Pah1 deletion, though these vacuoles were able to reform after osmotic shock, similar to the wild type background, but unlike either single deletion strain. This strain displayed reduced fusion and, interestingly, what appeared to be either the aberrant production, or degradation, of proteins. This observation points to a potentially more global cause for the observed phenotypes.

Graduation Semester

2014-08

Permalink

http://hdl.handle.net/2142/50420

Copyright and License Information

Copyright 2014 Colin Stoy

Owning Collections