Arabidopsis 3-hydroxy-3-methylglutaryl-CoA reductase is regulated at the post-translational level in response to alterations of the sphingolipid and the sterol biosynthetic pathways.

3-Hydroxy-3-methylglutaryl-CoA reductase (HMGR, EC 1.1.1.

Arabidopsis thaliana expresses two functional isoforms of Arvp, a protein involved in the regulation of cellular lipid homeostasis.

Arv1p is involved in the regulation of cellular lipid homeostasis in the yeast Saccharomyces cerevisiae. Here, we report the characterization of the two Arabidopsis thaliana ARV genes and the encoded proteins, AtArv1p and AtArv2p. The functional identity of AtArv1p and AtArv2p was demonstrated by complementation of the thermosensitive phenotype of the arv1Delta yeast mutant strain YJN1756.

Distinct light-mediated pathways regulate the biosynthesis and exchange of isoprenoid precursors during Arabidopsis seedling development.

Plants synthesize an astonishing diversity of isoprenoids, some of which play essential roles in photosynthesis, respiration, and the regulation of growth and development. Two independent pathways for the biosynthesis of isoprenoid precursors coexist within the plant cell: the cytosolic mevalonic acid (MVA) pathway and the plastidial methylerythritol phosphate (MEP) pathway. In at least some plants (including Arabidopsis), common precursors are exchanged between the cytosol and the plastid.

Characterization of dehydrodolichyl diphosphate synthase of Arabidopsis thaliana, a key enzyme in dolichol biosynthesis.

The enzyme dehydrodolichyl diphosphate (dedol-PP) synthase is a cis-prenyltransferase that catalyzes the synthesis of dedol-PP, the long-chain polyprenyl diphosphate used as a precursor for the synthesis of dolichyl phosphate. Here we report the cloning and characterization of a cDNA from Arabidopsis thaliana encoding dedol-PP synthase. The identity of the cloned enzyme was confirmed by functional complementation of a yeast mutant strain defective in dedol-PP synthase activity together with the detection of high levels of dedol-PP synthase activity in the transformed yeast mutant.