RT Journal Article SR Electronic T1 Regulation of poplar isoprenoid biosynthesis by methylerythritol phosphate and mevalonic acid pathways interactions JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.07.22.216804 DO 10.1101/2020.07.22.216804 A1 Ali Movahedi A1 Hui Wei A1 Boas Pucker A1 Weibo Sun A1 Dawei Li A1 Liming Yang A1 Qiang Zhuge YR 2021 UL http://biorxiv.org/content/early/2021/10/10/2020.07.22.216804.abstract AB Plants use two distinct isoprenoid biosynthesis routes: methylerythritol phosphate (MEP) and mevalonic acid (MVA) pathways. The rate-limiting enzymes of the MEP pathway are 1-deoxy-D-xylulose5-phosphate synthase (DXS) and 1-deoxy-D-xylulose5-phosphate reductoisomerase (DXR). 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes the rate-limiting step in the MVA pathway. Previously, overexpression of Populus trichocarpa PtDXR was found to upregulate resistance against salt and drought stresses. We showed while PtHMGR overexpressors (OEs) exhibited different MEP- and MVA-related gene expressions than non-transgenic poplars (NT), the PtDXR-OEs revealed upregulated MEP-related and downregulated MVA-related gene expressions. PtDXR and PtHMGR overexpressions caused changes in MVA-derived trans-zeatin-riboside, isopentenyl adenosine, castasterone, and 6-deoxocastasterone well as MEP-derived carotenoids and gibberellins. In PtHMGR-OEs, the accumulated geranyl diphosphate synthase (GPS) and geranyl pyrophosphate synthase (GPPS) transcript levels in the MEP pathway led to an accumulation of MEP-derived isoprenoids. In contrast, upregulation of farnesyl diphosphate synthase (FPS) expression in the MVA pathway contributed to increased levels of MVA-derived isoprenoids. In addition, PtHMGR-OEs increased MEP-related GPS and GPPS transcript levels, expanded MEP-derived isoprenoid levels, changed FPS transcript levels, and affected MVA-derived isoprenoid yields. These results suggest that interaction exists between the MVA- and MEP-pathways.Competing Interest StatementThe authors have declared no competing interest.