A conserved, lipid-mediated sorting mechanism of yeast Ist2 and mammalian STIM proteins to the peripheral ER

• Verfasst von: Ercan, Ebru [VerfasserIn]
• Verfasst von: Engel, Ulrike [VerfasserIn]
• Verfasst von: Temmerman, Koen [VerfasserIn]
• Verfasst von: Nickel, Walter [VerfasserIn]
• Verfasst von: Seedorf, Matthias [VerfasserIn]
• Titel: A conserved, lipid-mediated sorting mechanism of yeast Ist2 and mammalian STIM proteins to the peripheral ER
• Verf.angabe: Ebru Ercan, Frank Momburg, Ulrike Engel, Koen Temmerman, Walter Nickel and Matthias Seedorf
• Umfang: 17 S.
• Fussnoten: Gesehen am 22.05.2017
• Titel Quelle: Enthalten in: Traffic
• Jahr Quelle: 2009
• Band/Heft Quelle: 10(2009), 12, S. 1802-1818
• ISSN Quelle: 1600-0854
• DOI: doi:10.1111/j.1600-0854.2009.00995.x
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1558866957

Abstract

Sorting of yeast Ist2 to the plasma membrane (PM) or the cortical endoplasmic reticulum (ER) requires a cortical sorting signal (CSSIst2) that interacts with lipids including phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) at the PM. Here, we show that the expression of Ist2 in mammalian cells resulted in a peripheral patch-like localization without any detection of Ist2 at the cell surface. Attached to C-termini of mammalian integral membrane proteins, the CSSIst2 targeted these proteins to PM-associated domains of the ER and abolished trafficking via the classical secretory pathway. The interaction of integral membrane proteins with PI(4,5)P2 at the PM created ER-PM contacts. This process is similar to the regulated coupling of ER domains to the PM via stromal interaction molecule (STIM) proteins during store-operated Ca2+ entry (SOCE). The CSSIst2 and the C-terminus of the ER-located Ca2+ sensor STIM2 were sufficient to bind PI(4,5)P2 and PI(3,4,5)P3 at the PM, showing that an evolutionarily conserved mechanism is involved in the sorting of integral membrane proteins to PM-associated domains of the ER. Yeast Ist2 and STIM2 share a common basic and amphipathic signal at their extreme C-termini. STIM1 showed binding preference for liposomes containing PI(4,5)P2, suggesting a specific contribution of lipids to the recruitment of ER domains to the PM during SOCE.