Rosa roxburghii Tratt.(Cili)is a species of rose fruit with distinctive characteristics,combining medicinal and edible values.In recent years,it has become the focus of attention in the field of nutrition and health.F...Rosa roxburghii Tratt.(Cili)is a species of rose fruit with distinctive characteristics,combining medicinal and edible values.In recent years,it has become the focus of attention in the field of nutrition and health.From a health perspective,the core advantage of R.roxburghii lies in its high concentration of bioactive substances.Among these substances,pentacyclic triterpenoids are regarded as one of the key substances that contribute to its health-promoting effects.However,the regulatory mechanisms of triterpenoid biosynthesis remain unclear.The present study found that ultraviolet-B(UV-B)radiation increased the total triterpene content of R.roxburghii by 1.49-fold.The key cyclase gene RrOSC4 encodes an oxidosqualene cyclase implicated in the formation ofα/β-amyrin skeletons under UV-B radiation.Co-expression network and promoter analyses identified RrMYB62 as a key regulator of triterpenoid biosynthesis.Furthermore,over-expression of RrMYB62 upregulated the expression of RrOSC4,leading to increased pentacyclic triterpenoids content in‘NC89’tobacco leaves.Results from yeast one-hybrid,dual-luciferase activity and electrophoretic mobility shift assays demonstrated that RrMYB62 directly binds and activates the promoter of RrOSC4 to regulate triterpenoid biosynthesis.Taken together,our findings demonstrate that triterpenoid biosynthesis in R.roxburghii exposed to UV-B radiation is regulated by the RrMYB62-RrOSC4 module.This study revealed the interplay between light signaling and functional phytochemicals,offering a molecular basis for enhancing the fruit quality in the field of food application.展开更多
基金supported by the National Key Research and Development Program of China(2024YFD1300803)the Fundamental Research Funds for the Central Universities(2572023AW35)National Natural Science Foundation of China(32501698).
文摘Rosa roxburghii Tratt.(Cili)is a species of rose fruit with distinctive characteristics,combining medicinal and edible values.In recent years,it has become the focus of attention in the field of nutrition and health.From a health perspective,the core advantage of R.roxburghii lies in its high concentration of bioactive substances.Among these substances,pentacyclic triterpenoids are regarded as one of the key substances that contribute to its health-promoting effects.However,the regulatory mechanisms of triterpenoid biosynthesis remain unclear.The present study found that ultraviolet-B(UV-B)radiation increased the total triterpene content of R.roxburghii by 1.49-fold.The key cyclase gene RrOSC4 encodes an oxidosqualene cyclase implicated in the formation ofα/β-amyrin skeletons under UV-B radiation.Co-expression network and promoter analyses identified RrMYB62 as a key regulator of triterpenoid biosynthesis.Furthermore,over-expression of RrMYB62 upregulated the expression of RrOSC4,leading to increased pentacyclic triterpenoids content in‘NC89’tobacco leaves.Results from yeast one-hybrid,dual-luciferase activity and electrophoretic mobility shift assays demonstrated that RrMYB62 directly binds and activates the promoter of RrOSC4 to regulate triterpenoid biosynthesis.Taken together,our findings demonstrate that triterpenoid biosynthesis in R.roxburghii exposed to UV-B radiation is regulated by the RrMYB62-RrOSC4 module.This study revealed the interplay between light signaling and functional phytochemicals,offering a molecular basis for enhancing the fruit quality in the field of food application.
