Topinformationen

Vortrag von Claudia Matthäus

Vortragstitel: "Novel insights in caveolae mediated lipid trafficking"
Anlass: SFB - Seminar
Beginn: 17.10.2024 - 16:15 Uhr
Ort: CellNanOs, 38/201

Über die Vortragende: Prof. Dr. Claudia Matthäus forscht im Institut für Zelluläre Physiologie der Ernährung an der Universität Potsdam.

Inhalt des Vortrags: Caveolae are 50-90 nm sized plasma membrane invaginations that are abundantly found in adipocytes, myocytes and endothelial cells. Structurally, caveolae are formed by a protein coat of caveolins and cavins. Additionally, membrane binding proteins like EHD2 regulate caveolae dynamics and endocytosis. Mice lacking caveolae revealed an impaired lipid metabolism, reduced weight gain and lipodystrophy. As caveolae are mobile membrane domains which can get endocytosed as small vesicles, it was proposed that caveolae can migrate to lipid droplets. However, up to date it is not understood how caveolae trafficking is induced and what happens mechanistically at the lipid droplet coat. By using fibroblasts and 3T3-L1 adipocytes we investigate the involvement of caveolae trafficking in cellular lipid metabolism. We showed that changing the rate of caveolae endocytosis results in altered lipid uptake. Thereby, either an increased caveolae internalization or raised numbers of caveolae lead to an increased fatty acid uptake and larger lipid droplets. Platinum replica electron microscopy revealed that the fatty acid treatment itself triggers caveolae detachment from the plasma membrane. Live imaging of caveolae by TIRF and confocal microscopy showed that caveolae migrate to lipid droplets after lipid treatment where they may form a membrane contact with the lipid droplet coat. A split-APEX2 approach verified the direct trafficking of caveolae from the plasma membrane to lipid droplets. Taken together, here we present novel insights in caveolae mediated lipid trafficking.