海拔高度对蒙古黄芪主要药效成分积累及其关键酶基因表达量影响研究

Study on effect of altitude on accumulation of main active components and expression of key enzyme genes of Astragalus mongholicus

目的研究不同海拔高度与蒙古黄芪Astragalus membranaceus var.mongholicus主要药效成分含量及其关键酶基因表达量之间的关系。方法采用HPLC法检测黄芪根中黄芪甲苷与毛蕊异黄酮葡萄糖苷的含量,采用实时荧光定量PCR法检测黄芪甲苷生物合成过程中关键酶基因乙酰辅酶A乙酰基转移酶[AACT,acetoacetyl-co zyme A(CoA)thiolase]、3-羟基-3-甲基戊二酰辅酶A合酶(HMG-CoA synthase,HMGS)、3-羟基-3-甲基戊二酰辅酶A还原酶[3-hydroxy-3-methylglutaryl coenzyme A(HMG-CoA)reductase,HMGR]、异戊二烯焦磷酸异构酶(iso-pentenyl diphosphate isomerase,IDI)、法尼基焦磷酸合酶(farnesyl diphosphate synthase,FPS)、鲨烯合酶(squalene synthase,SS)、鲨烯环氧酶(squalene epoxidase,SE)、环阿尔庭烷合酶(cycloartenol synthase,CAS)基因的表达量。结果4个样地中样地HQ-2(内蒙呼和浩特可可以力更镇)中黄芪甲苷含量、毛蕊异黄酮葡萄糖苷含量及总皂苷含量普遍高于其他样地;相关性分析表明,海拔高度对黄芪总皂苷合成的影响较大,IDI、SE和SS基因在黄芪总皂苷的合成过程中起主要作用,海拔高度有利于IDI、SE和SS基因的表达,海拔高度对黄芪皂苷合成途径中关键酶基因具有一定的调控作用。结论在处于海拔1730 m左右的地区种植蒙古黄芪有利于其药效成分的积累。

Objective Astragalus membranaceus was used as the experimental material to study the relationship between different altitude and the content of main effective components and the expression of key enzyme genes of A.membranaceus.Methods The content of astragaloside and genistein glucoside in Astragalus root was detected by HPLC,and the expression of key enzyme genes(AACT,HMGR,CAS,FPS,HMGs,IDI,SE,SS)in astragaloside biosynthesis was detected by qRT-PCR.Results The contents of astragaloside a,isoflavone glucoside,and total saponin in HQ-2 of four plots in Huhhot were higher than those in other plots.The correlation analysis showed that the altitude had a great influence on the synthesis of astragalus total saponins,and the genes of IDI,SE and SS played a major role in the synthesis of astragalus total saponins.Altitude was favorable for the expression of IDI,SE and SS genes,and it also had a certain regulatory effect on key enzyme genes in astragaloside synthesis pathway.Conclusion Planting A.mongholicus at an altitude of 1730 meters is beneficial to the accumulation of its active components.