Effect of specific inhibitor of 3-hydroxy-3-methylglutaryl-CoA synthase (F‐244) on Arabidopsis

Abstract

Isoprenoid compounds including chlorophylls and carotenoids, cytokinins, sterols, brassinosteroids, precursors of abscisic acid, monoterpenes and sesquiterpenes, promote the plant in many physiological processes and its survival. 3-Hydroxy-3-methylglutaryl-CoA synthase (HMGS) is an enzyme responsible for the condensation of acetoacetyl-CoA and acetyl-CoA into HMG-CoA, which involves in the second step in the mevalonate (MVA) biosynthesis pathway. MVA would subsequently be converted into IPP, a universal precursor for various isoprenoids. In plants, emerging studies show that the overexpression of HMGS in plants could significantly enhance germination, reproduction, seed production and stress tolerance, demonstrating that HMGS could be a potential target for manipulating plant growth regulation. Some of the most extensively-studied HMGS are the Brassica juncea BjHMGS1 and its mutant forms. Transgenic Arabidopsis and tobacco overexpressing BjHMGS1 and its mutant forms as well as the Arabidopsis knock-out mutant have been used to understand how HMGS affects physiological functions, downstream isoprenoid gene expression and end-product sterol production. In this study, to better understand the function of HMGS in plant development, an HMGS inhibitor was used to investigate if the metabolic flux from cytosolic acetyl-CoA to isoprenoids could be abrogated in Arabidopsis seedlings. Results on phenotypic changes arising from inhibitor use and analyses using qRT-PCR and proteomics will be presented.