A role for eisosomes in maintenance of plasma membrane phosphoinositide levels

作者：Froehlich Florian; Christiano Romain; Olson Daniel K; Alcazar Roman Abel; DeCamilli Pietro; Walther Tobias C^*

来源：Molecular Biology of the Cell, 2014, 25(18): 2797-2806.

DOI：10.1091/mbc.E13-11-0639

The plasma membrane delineates the cell and mediates its communication and material exchange with the environment. Many processes of the plasma membrane occur through interactions of proteins with phosphatidylinositol(4,5)-bisphosphate (PI(4,5)P-2), which is highly enriched in this membrane and is a key determinant of its identity. Eisosomes function in lateral organization of the plasma membrane, but the molecular function of their major protein subunits, the BAR domain-containing proteins Pil1 and Lsp1, is poorly understood. Here we show that eisosomes interact with the PI(4,5)P-2 phosphatase Inp51/Sjl1, thereby recruiting it to the plasma membrane. Pil1 is essential for plasma membrane localization and function of Inp51 but not for the homologous phosphatidylinositol bisphosphate phosphatases Inp52/Sjl2 and Inp53/Sjl3. Consistent with this, absence of Pil1 increases total and available PI(4,5)P-2 levels at the plasma membrane. On the basis of these findings, we propose a model in which the eisosomes function in maintaining PI(4,5)P-2 levels by Inp51/Sjl1 recruitment.

• 出版日期2014-9-15