In silico characterization and differential expression pattern analysis of conserved HMG CoA reductase domain isolated from Aconitum balfourii Stapf.

The 3-hydroxy-3-methyl glutaryl CoA reductase (HMGR) is the key enzyme of mevalonate pathway in plants. A partial genomic DNA fragment encoding HMGR conserved domain (denoted as AbHMGR) is isolated from Aconitum balfourii Stapf. It comprises 871 bp encoding 290 amino acids. In silico analysis reveals that it had extensive similarities to other plant HMGR gene. Domain analysis of AbHMGR showed two highly conserved NADPH and HMG CoA domains. Docking study predicted inhibitor, substrate and cofactor binding sites in the protein. Expression analysis revealed that AbHMGR is similarly expressed in all tested tissues with differential pattern. The highest expression was found in leaf tissue. However, fold expression in root and shoot tissue was almost similar. Enzyme activity of HMGR was found to be much higher in leaf tissue as compared to other tissues. The highest aconitine content (0.015 %) was obtained in root tissues. Our data laid a foundation for further investigation of HMGR role in Aconitum balfourii.