Active expression and core sequnce analysis of HMGR gene promoter from Artemisia annua / 中草药

ABSTRACT

Objective: To analyze the expression character, screen the core sequence of 3-hydroxy-3-methyl glutaryl coenzyme A (HMGR) promoter from Artemisia annua, and provide a theoretical basis for the efficient biosynthesis of artemisinin. Methods: In this study, β-glucoside acid enzyme (GUS) gene was used as the report gene and constructed five different length expression vectors, including the whole length of HMGR promoter, based on the cloned HMGR promoter sequences, and successfully obtained transgenic plants by the method of agrobacterium mediation transform tobacco, then the tobacco was stained by GUS. Results: The GUS staining showed that the blue color could detect in the roots, stems, leaves, flowers, and fruit pods. And the leaves in the lower part could easily get the blue color than the leaves in the top part, this may due to that the accumulation of HMGR metabolite product is more and the permeability in leaves is better in the mature leaves. The results also showed that the color showed shallow in heat and drought stresses, and with no significant difference in cold stress, the tobacco leaves with paragraph of P-HMGR-1, P-HMGR-2, and P-HMGR-3 showed blue color but did not find blue in leaves with paragraph of P-HMGR-4, P-HMGR-5. Conclusion: HMGR promoter has a stable expression during the whole growth period of tobacco. HMGR promoter was not sensitive with cold environment, but sensitive with heat and draught resistance. The key area of HMGR promoter was in P-HMGR-3. And there are some regulatory elements but no necessary part of HMGR promoter between the non overlap area of P-HMGR-3 and P-HMGR-2.