YEAST 2017

28th International Conference on Yeast Genetics and Molecular Biology (ICYGMB)

August 27 – September 1, 2017
Prague, Czech Republic

Paper ID: 303

Never Walk Alone – Contact Sites between Lipid Droplets and Other Organelles.

Bohnert Maria1, Eisenberg-Bord Michal1, Weill Uri1, Mari Muriel2, Castro Inês G.1, Rosenfeld-Gur Eden3, Moldavski Ofer1, Soni Krishnakant G.4, Levine Tim P.5, Futerman Anthony H.3, Reggiori Fulvio2, Bankaitis Vytas A.4, Schuldiner Maya1

1 Department of Molecular Genetics, Weizmann Institute of Science (Israel)
2 Department of Cell Biology, University of Groningen (Netherlands)
3 Department of Biomolecular Sciences, Weizmann Institute of Science (Israel)
4 Department of Molecular and Cellular Medicine, Texas A&M Health Science Center (USA)
5 UCL Institute of Ophthalmology (United Kingdom)


Lipid droplets store lipids and thus serve both as an energy reservoir and as a source of building blocks for the organellar membrane systems. Therefore, lipid droplet biology depends on tight communication with other organelles. One important way of interorganellar communication is by formation of contact sites, places where the surfaces of different organelles are actively positioned in very close proximity to each other. We can detect distinct subpopulations of lipid droplets at the surface of virtually all other organelles in S. cerevisiae that appear to be tethered to their surrounding membranes. 

We find that a lipid droplet subpopulation positioned adjacent to the NVJ, the contact site between the nucleus and the vacuole/lysosome, is equipped with a unique surface proteome. In an attempt to identify molecular factors determining the identity of these lipid droplets, we screened ~6000 mutants for mislocalization of a subpopulation marker, Pdr16, and identified Ldo45 (lipid droplet organization protein of 45 kDa) as a crucial targeting determinant. Ldo45 is derived from a splicing event connecting two adjacent genes (YMR147W and YMR148W/OSW5/LDO16). Ldo proteins are evolutionary conserved proteins that cooperate with the contact site component seipin, and determine lipid droplet identity by defining their positioning and surface protein composition. Our results suggest a contact site based mechanism to imprint functional specialization of organelles, opening a door to deeper understanding of metabolic decisions in the cell.

Lipid droplet, Organelle contact site, Cellular organization
Presented as:
  Oral presentation [S4-3] in S4 Organelle dynamics

Institute of Microbiology

YEAST 2017
28th International Conference on Yeast Genetics and Molecular Biology (ICYGMB)

Copyright © Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic, 2016-2017  |  Privacy policy

Developed by SEOman. Powered by open source: LAMP, jQuery and Bootstrap.