Effect of V-ATPase on the lipid production in Phaeodactylum tricornutum

Abstract

Vacuolar H + -ATPase (V-ATPase) is one of the key proton pump localized on tonoplast and other endomembrane system, which functions in ATP hydrolysis and involved in various physiological events and stress responses. Our recent report has suggested that downregulation of V-ATPase activity inhibited the lipid production in Phaeodactylum tricornutum . However, the lipid components did not affect by bafilomycin A1 (BFA1) treatment, one of the V-ATPase specific inhibitor. Further ananylsis indicated that intracellular pH and nitrogen depletion were delayed after BFA1 treatment. To reveal the molecular mechanism of V-ATPase in regultion of lipid production in Phaeodactylum tricornutum , RNA-Seq analysis was applied. Our data revealed that carbon flow shunted to starch production other than lipid production under BFA1 treatment. Additionally, genes involved in protein trafficking was downregulated while that involved in lipid catabolic metabolism was upregulated under BFA1 treatment. It was first shown that the relationship between V-ATPase and lipid production in plant. However, the precise target of V-ATPase on the singal pathway of lipid production is still not clear enough. It should be further investigaed by cell biology and protein technology in the future.