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Updated: Jun 10, 2026
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PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions
Published on: July 27, 2017
Surprising roles for phospholipid binding proteins revealed by high throughput genetics
Marissa A LeBlanc1, Christopher R McMaster
1Department of Pediatrics and Department of Biochemistry and Molecular Biology, Atlantic Research Centre, Dalhousie University, Halifax, NS, Canada.
Summary
Synthetic genetic analysis (SGA) in yeast revealed that Sec14 and Kes1 proteins coordinate Golgi PI-4-phosphate levels, essential for regulating vesicular transport. This finding clarifies lipid-binding protein roles in cellular transport pathways.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Saccharomyces cerevisiae is a model organism for studying lipid metabolism due to conserved pathways and genetic tractability.
- Synthetic Genetic Analysis (SGA) enables high-throughput identification of gene functions and pathways.
- Sec14, a phosphatidylcholine-phosphatidylinositol transfer protein, is crucial for trans-Golgi vesicular transport.
Purpose of the Study:
- To elucidate the roles of lipid-binding proteins Sec14 and Kes1 in vesicular transport using SGA.
- To investigate the genetic interactions between Sec14 and Kes1 in regulating cellular functions.
- To identify the specific lipid pools and enzymes involved in the pathways regulated by Sec14 and Kes1.
Main Methods:
- Utilized Synthetic Genetic Analysis (SGA) to screen for genetic interactions and identify gene functions.
- Performed genetic and cell biological analyses to validate SGA findings.
- Compared SGA screen data with existing databases for further insights.
Main Results:
- Inactivating KES1 restored vesicular transport and growth in Sec14-deficient cells, highlighting a functional relationship.
- SGA identified roles for Kes1 and Sec14 in regulating Golgi PI-4-phosphate (PI-4-P) levels and function.
- Sec14 regulates vesicular transport from both the trans-Golgi and endosomes to the trans-Golgi.
- Kes1-affected PI-4-P pools are generated by the PI 4-kinase Pik1.
Conclusions:
- Sec14 and Kes1 coordinate the regulation of Pik1-generated Golgi PI-4-P.
- This coordinated regulation is essential for vesicular transport into and out of the trans-Golgi.
- The study clarifies the intricate roles of these lipid-binding proteins in maintaining cellular transport homeostasis.
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