Updated project metadata. 3-Hydroxy-3-methylglutaryl-CoA synthase (HMGS) is the second enzyme in the mevalonate pathway. While the recombinant Brassica juncea HMGS1 (BjHMGS1) mutant S359A displayed 10-fold higher enzyme activity than wild-type (wt) BjHMGS1, transgenic tobacco overexpressing S359A (OE-S359A) exhibited greater sterol content, growth rate and seed yield than OE-wtBjHMGS1. To explore the mechanism of HMGS and its mutant (S359A) in promotion of plant growth, SWATH-MS quantitative proteomics analysis was performed.