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bioRxiv · 10.1101/2020.12.16.423147

Trans-Golgi network-lipid droplet contacts maintain the TGN integrity and function via lipid transfer activities of VPS13B

Du, Y.·Xiong, J.·Ji, W.
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Abstract

While the physical interactions between the Golgi apparatus (Golgi) and lipid droplets (LDs) have been suggested through system-level imaging, the bona fide and functional Golgi-LD membrane contact sites (MCSs) remain largely uncharacterized. Here, we demonstrate that vacuolar protein sorting-associated protein 13B (VPS13B) mediates trans-Golgi network (TGN)-LD interactions. VPS13B is specifically accumulated at TGN-LD MCSs with its C-terminal region targeting LDs via an amphipathic helix while a putative WD40 module and a C-terminal Pleckstrin homology (PH) domain independently recognizing TGN via directly binding to Rab6. A putative lipid transfer domain (LTD) at the N-terminal portion of VPS13B binds glycerophospholipids in vitro. VPS13B suppression results in severe fragmentation of the TGN, an effect that can be almost completely rescued by the expression of VPS13B-LTD. Collectively, our findings demonstrate that VPS13B mediates lipid transfer at TGN-LD MCSs to maintain TGN integrity and function.

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Du, Y., Xiong, J., Ji, W.. 2020-12-16. Trans-Golgi network-lipid droplet contacts maintain the TGN integrity and function via lipid transfer activities of VPS13B. https://doi.org/10.1101/2020.12.16.423147

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