Lipidomic insights into the response of Arabidopsis sepals to mild heat stress

Abstract Arabidopsis sepals coordinate flower opening in the morning as ambient temperature rises; however, underlying molecular mechanisms are poorly understood. Mutation of one heat shock protein encoding gene, HSP70-16 , impaired sepal stress responses (HSR), disrupting lipid metabolism, especially cuticular lipids, leading to abnormal opening. To further explore, what extent, lipids play roles this process, study, we compared lipidomic changes hsp70-16 and vdac3 (mutant a voltage-dependent anion channel, VDAC3, an interactor) grown under both normal (22 °C) mild (27 °C, HS) temperatures. Under temperature, neither nor showed significant total lipids; but not exhibited reductions ratios all detected 11 classes, except monogalactosyldiacylglycerols (MGDGs). HS dramatic reduction lipids. In addition, accumulation plastidic sulfoquinovosyldiacylglycerols (SQDGs) phosphatidylglycerols (PGs), whereas had triacylglycerols (TAGs) simultaneous SQDGs phospholipids (PLs), such phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), phosphatidylserines (PSs). These findings revealed that impact on lipidome is influenced by genetic factors, further, VDAC3 differently affect HS. Our studies provide insight into functions HSP VDAC proteins plant’s HSR, context floral development.