HMG1 — Lactuca sativa

Summary

LsHMG1 (HMG1) on chromosome 8 of garden lettuce encodes a hydroxymethylglutaryl-CoA reductase (HMGR), the enzyme that catalyses the committed step of the mevalonate (MVA) pathway. The gene is associated with the MVA pathway, isoprenoid, sterol, triterpenoid, saponin and terpenoid anabolism, as well as CoA and pyruvate metabolism. It has been linked to responses to jasmonic acid and absence of light, and to phenylpropanoid anabolism. The encoded protein localises to multiple membranes, including the ER, plastid, chloroplast, mitochondrial and peroxisome membranes. LsHMG1 is associated with plant height, biomass, photosynthetic rate, flowering time, male fertility, seed phytosterol content, herbivore resistance, pathogen and wound responses, and flower morphology and colour. Studies of related genes in other species link the HMGR family to isoprenoid biosynthesis, phytosterol content, and mevalonate pathway regulation.