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Applications of pHluorin for Quantitative, Kinetic and High-throughput Analysis of Endocytosis in Budding Yeast
Published on: October 23, 2016
Secretory vesicles externalize the major plasma membrane ATPase in yeast
C L Holcomb1, W J Hansen, T Etcheverry
1Department of Biochemistry, University of California, Berkeley 94720.
The Journal of Cell Biology
|March 1, 1988
Summary
Yeast cell surface growth relies on coordinated secretion and membrane assembly. This study shows that plasma membrane ATPase and acid phosphatase are transported together in vesicles, even in secretion-defective yeast mutants.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Yeast cell surface growth involves constitutive secretion and plasma membrane assembly.
- The fusion of vesicles with the bud membrane is a critical step in this process.
- Understanding the coordination between secretion and membrane assembly is key to cell growth.
Purpose of the Study:
- To investigate the biogenesis of plasma membrane ATPase (PM ATPase) in Saccharomyces cerevisiae.
- To examine the role of the secretory pathway in PM ATPase export.
- To analyze vesicle transport in secretion-defective mutants.
Main Methods:
- Utilized secretion-defective (sec) yeast strains, specifically sec1 mutants.
- Examined the biogenesis of PM ATPase.
- Performed biochemical characterization of accumulated Golgi-derived vesicles.
Main Results:
- PM ATPase is synthesized as a 106-kD polypeptide without significant modification during transit.
- Export of PM ATPase is dependent on the secretory pathway.
- In sec1 mutants, accumulated Golgi-derived vesicles contain both PM ATPase and acid phosphatase, indicating co-transport within a single vesicle species.
Conclusions:
- The secretory pathway is essential for the transport of PM ATPase to the plasma membrane.
- PM ATPase and secretory enzymes like acid phosphatase share a common transport route within vesicles.
- This finding provides insight into the coordinated mechanisms of secretion and membrane assembly in yeast.
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