Skip to main content
bioRxiv
  • Home
  • About
  • Submit
  • ALERTS / RSS
Advanced Search
New Results

Anisotropy of plasmalemmal sterols and cell mating require StARkin domain proteins Ysp2 and Lam4

Neha Chauhan, Gregory D. Fairn
doi: https://doi.org/10.1101/2021.09.30.462584
Neha Chauhan
1Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Unity Health Toronto, Toronto, Canada
2Department of Biochemistry, University of Toronto, Toronto, Canada
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Gregory D. Fairn
1Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Unity Health Toronto, Toronto, Canada
2Department of Biochemistry, University of Toronto, Toronto, Canada
3Department of Pathology, Dalhousie University, Halifax, Canada
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: gfairn@dal.ca
  • Abstract
  • Full Text
  • Info/History
  • Metrics
  • Preview PDF
Loading

Abstract

In the budding yeast S. cerevisiae Cdc42 is required for polarized growth and the formation of mating projections (shmoos). Negatively charged lipids including phosphatidylserine and phosphatidylinositol 4,5-bisphosphate support a positive feedback loop that recruits Cdc42 effectors and MAP kinase scaffolds, many of which contain polybasic patches that directly interact with the membrane. Here, using genetically encoded sterol sensor ALOD4 we find that ergosterol is accumulated in the cytosolic leaflet of buds and shmoos. The accumulation of ergosterol in the plasma membrane requires both Osh and Lam proteins however cells lacking Ysp2/Lam2 and Lam4 displayed a reversal in the polarity of ergosterol. The redistribution of ergosterol impairs the polarization of phosphatidylserine and phosphatidylinositol 4,5-bisphophate which further impacts shmoo formation, MAPK signaling and mating efficiency. Our observations demonstrate that the ability of Lam proteins to deliver ergosterol from the plasma membrane to the ER helps maintain a gradient of ergosterol which in turn supports robust cell polarity.

Summary The sterol sensor ALOD4 is enriched at sites of polarized growth. Elimination of the Osh proteins solubilized the ALOD4 whereas elimination of Ysp2 and Lam4 reversed ALOD4 polarization. Cells lacking Ysp2 and Lam4 have defects in mating and MAP kinase signaling.

Competing Interest Statement

The authors have declared no competing interest.

Copyright 
The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license.
Back to top
PreviousNext
Posted September 30, 2021.
Download PDF
Email

Thank you for your interest in spreading the word about bioRxiv.

NOTE: Your email address is requested solely to identify you as the sender of this article.

Enter multiple addresses on separate lines or separate them with commas.
Anisotropy of plasmalemmal sterols and cell mating require StARkin domain proteins Ysp2 and Lam4
(Your Name) has forwarded a page to you from bioRxiv
(Your Name) thought you would like to see this page from the bioRxiv website.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Share
Anisotropy of plasmalemmal sterols and cell mating require StARkin domain proteins Ysp2 and Lam4
Neha Chauhan, Gregory D. Fairn
bioRxiv 2021.09.30.462584; doi: https://doi.org/10.1101/2021.09.30.462584
Digg logo Reddit logo Twitter logo Facebook logo Google logo LinkedIn logo Mendeley logo
Citation Tools
Anisotropy of plasmalemmal sterols and cell mating require StARkin domain proteins Ysp2 and Lam4
Neha Chauhan, Gregory D. Fairn
bioRxiv 2021.09.30.462584; doi: https://doi.org/10.1101/2021.09.30.462584

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Subject Area

  • Cell Biology
Subject Areas
All Articles
  • Animal Behavior and Cognition (3573)
  • Biochemistry (7517)
  • Bioengineering (5479)
  • Bioinformatics (20675)
  • Biophysics (10257)
  • Cancer Biology (7931)
  • Cell Biology (11580)
  • Clinical Trials (138)
  • Developmental Biology (6563)
  • Ecology (10135)
  • Epidemiology (2065)
  • Evolutionary Biology (13537)
  • Genetics (9497)
  • Genomics (12788)
  • Immunology (7871)
  • Microbiology (19451)
  • Molecular Biology (7614)
  • Neuroscience (41872)
  • Paleontology (306)
  • Pathology (1252)
  • Pharmacology and Toxicology (2179)
  • Physiology (3249)
  • Plant Biology (7005)
  • Scientific Communication and Education (1291)
  • Synthetic Biology (1942)
  • Systems Biology (5406)
  • Zoology (1107)