Vortrag von Oliver Schmidt
Vortragstitel: "Regulation of sphingolipid metabolism by ORMDL family proteins in budding yeast"
Anlass: SFB SonderSeminar
Host: Florian Fröhlich
Beginn: 21.09.2022 - 16:15 Uhr
Ort: CellNanOs 38/201
Über den Vortragenden: Oliver Schmidt ist Außerordentlicher Professor für Zellbiologie an der Medizinischen Universität Innsbruck
Inhalt des Vortrags: The ORMDL family of ER membran proteins constitutes major regulators of sphingolipid metabolism by controling activity of the rate limiting enzyme serine-palmitoyl-CoA transferase (SPT). Disturbance of this regulatory module has severe pathological consequences in humans. The genomes of most organisms encode for more than one ORMDL protein (humans 3; budding yeast 2) but their different physiological roles are unclear. We recently described a fundamentally different regulation of the two yeast paralogues, Orm1 and Orm2: target-of-rapamycin complex 2-dependent phosphorylatation of Orm2 leads to export of the protein from the ER and destruction by endosome and Golgi-associated degradation (EGAD; a new membrane protein degradation pathway recently described by us). In contrast, upon analogous phosphorylation Orm1 is retained stably in the ER. We now follow up on these observations to better characterize differences between the highly homolous yeast Orm1 and Orm2 proteins, in order to understand why most organisms rely on more than ORMDL family protein to control SPT activity and to maintain sphingolipid homeostasis.