Annexin A2 promotes phagophore assembly by enhancing Atg16L⁺ vesicle biogenesis and homotypic fusion.

ABSTRACT: Plasma membrane budding of Atg-16L-positive vesicles represents a very early event in the generation of the phagophore and in the process of macroautophagy. Here we show that the membrane curvature-inducing protein annexin A2 contributes to the formation of these vesicles and their fusion to form phagophores. Ultrastructural, proteomic and FACS analyses of Atg16L-positive vesicles reveal that 30% of Atg16L-positive vesicles are also annexin A2-positive. Lipidomic analysis of annexin A2-deficient mouse cells indicates that this protein plays a role in recruiting phosphatidylserine and phosphatidylinositides to Atg16L-positive vesicles. Absence of annexin A2 reduces both vesicle formation and homotypic Atg16L vesicle fusion. Ultimately, a reduction in LC3 flux and dampening of macroautophagy

SUBMITTER: Morozova K 

PROVIDER: S-EPMC4299943 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature