The yeast p24 complex regulates GPI-anchored protein transport and quality control by monitoring anchor remodeling

نویسندگان

  • Guillaume A. Castillon
  • Auxiliadora Aguilera-Romero
  • Javier Manzano-Lopez
  • Sharon Epstein
  • Kentaro Kajiwara
  • Kouichi Funato
  • Reika Watanabe
  • Howard Riezman
  • Manuel Muñiz
چکیده

Glycosylphosphatidylinositol (GPI)-anchored proteins are secretory proteins that are attached to the cell surface of eukaryotic cells by a glycolipid moiety. Once GPI anchoring has occurred in the lumen of the endoplasmic reticulum (ER), the structure of the lipid part on the GPI anchor undergoes a remodeling process prior to ER exit. In this study, we provide evidence suggesting that the yeast p24 complex, through binding specifically to GPI-anchored proteins in an anchor-dependent manner, plays a dual role in their selective trafficking. First, the p24 complex promotes efficient ER exit of remodeled GPI-anchored proteins after concentration by connecting them with the COPII coat and thus facilitates their incorporation into vesicles. Second, it retrieves escaped, unremodeled GPI-anchored proteins from the Golgi to the ER in COPI vesicles. Therefore the p24 complex, by sensing the status of the GPI anchor, regulates GPI-anchored protein intracellular transport and coordinates this with correct anchor remodeling.

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عنوان ژورنال:

دوره 22  شماره 

صفحات  -

تاریخ انتشار 2011