Kinetics and targeting of Vipp1 aggregation in cyanobacteria

Abstract

The kinetics of regulation of vesicle-inducing protein in plastids (Vipp1), an essential protein in all oxygenic phototrophs, are not completely understood. Vipp1 is responsible for both membrane maintenance and damage repair processes, aggregating at sites of damage (proton leakage) or physical strain (responding to presence of anionic lipids). Herein we spatiotemporally resolve exchange between inactive cytoplasmic Vipp1 and these two functionalities. We demonstrate that Vipp1 can be aggregated to a specific site in the thylakoid membrane by laser damage, but this behavior appears to be mediated by a rapidly resolved secondary process, as cytoplasmic Vipp1 is rendered unresponsive to nearby damage on a time scale three orders of magnitude faster than the aggregation process itself. One Sentence SummaryVipp1 aggregation to points on the thylakoid is induced in response to specific damage and repair kinetics are observed.