The Two Classes of Ceramide Synthases Play Different Roles in Plant Immunity and Cell Death

• DOI: 10.3389/fpls.2022.824585
• Publication Date: 2022-04-07T05:57:11Z
• Authors: Hong-Yun Zeng; He-Nan Bao; Yi-Li Chen; Ding-Kang Chen; Kun Zhang; Shuai-Kang Liu; La Yang; Yong-Kang Li; Nan Yao
• Keywords: Plant Immunity

Ceramide synthases (CSs) produce ceramides from long-chain bases (LCBs). However, how CSs regulate immunity and cell death in Arabidopsis thaliana remains unclear. Here, we decipher the roles of two classes CS, CSI (LAG1 HOMOLOG 2, LOH2) CSII (LOH1/3), these processes. The loh1-2 loh1-1 loh3-1 mutants were resistant to bacterial pathogen Pseudomonas syringae pv maculicola (Psm) DG3 exhibited programmed (PCD), along with increased LCBs ceramides, at later stages. In loh1-2, Psm resistance, PCD, sphingolipid accumulation mostly suppressed by inactivation lipase-like proteins ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) PHYTOALEXIN DEFICIENT 4 (PAD4), partly loss SALICYLIC ACID INDUCTION 2 (SID2). LOH1 inhibitor fumonisin B1 (FB1) triggered EDS1/PAD4-independent LCB accumulation, EDS1/PAD4-dependent death, resistance Psm, C16 Cer accumulation. Loss LOH2 enhances FB1-, sphinganine-induced indicating that negatively regulates signaling inhibition. Like Cer, mediate signaling, through EDS1/PAD4 pathway. Our results show ceramide differentially PCD via subtle control Cers Arabidopsis.