Mining And Expression Analysis Of Genes Involved In The Valeric Acids Biosynthesis Of Valeriana Jatamansi Jones

Valeriana jatamansi Jones is a specie in Valeriana of Valerianaceae,and its root and rhizome are used as medicine.It is the only traditional Chinese medicine in the genus Valeriana that has been listed in the Chinese Pharmacopoeia,and it is also a national medicine shared by many ethnic minorities in Yunnan,Guizhou and Sichuan for a long time.The group of valeric acids mainly includes valeric acid and its derivatives acetovaleric acid and hydroxyvaleric acid,are sesquiterpenoids isolated from volatile oils of valerian plants,which are specific compounds of Valeriana species with sedative and anxiolytic properties.In this paper,we investigated three aspects,including the analysis of transcriptome data of V.jatamansi,prokaryotic expression and q RT-PCR analysis of genes involved in the synthesis of valeric acids and the investigation of adventitious roots of V.jatamansi,which may provide a foundation for the analysis of the valeric acids biosynthetic pathway in V.jatamansi.Through transcriptome sequencing and differential gene analysis in the biosynthesis pathway of valeric acids,the four elicitors of methyl jasmonate,yeast extract,salicylic acid,and silver nitrate were used to treat the tissue culture seedlings of V.jatamansi.It was found that there were 17 key enzymes for the synthesis of valeric acids.On this basis,the elicitors that could significantly increase the gene expression of these 17 enzymes were screened,and finally found that silver nitrate had the best induction effect.Two TPS genes were cloned from the tissue culture seedlings of V.jatamansi,and the full length of Vj TPS1 gene was 1689 bp,encoding562 amino acids;The total length of Vj TPS4 gene was 1638 bp,encoding 545 amino acids.The prokaryotic expression vectors of Vj TPS1 gene and Vj TPS4 gene were successfully constructed to realize the heterologous expression of these two genes.V.jatamansi clover leaf pieces were used as explants to induce adventitious roots,and the optimal solid medium for adventitious root growth was MS+0.5 mg/L NAA,and the optimal medium for adventitious root suspension culture was MS+0.5mg/L NAA.Adventitious roots and histiocyte seedlings of V.jatamansi were respectively treated with silver nitrate,and the expression changes of nine key enzyme genes were investigated by q RT-PCR technique,and the expression changes trend remained consistent with the transcriptome data,while the overall expression increased after treatment with silver nitrate.The results of metabolome sequencing of the adventitious roots and histiocyte seedlings of V.jatamansi showed that terpenes were the main volatile components in the adventitious roots and histiocyte seedlings of V.jatamansi.This paper provides a new idea for the study of the valeric acids biosynthetic pathway in V.jatamansi,and also provides a technical support for further industrialization on the adventitious roots of V.jatamansi.