过表达山豆根StLDC基因对烟草生物碱含量的影响OA

Lysine decarboxylase(LDC)is the first key enzyme gene in the biosynthetic pathway of quinolizidine al-kaloids.Based on the obtained full-length sequence of StLDC gene from Sophora tonkinensis,an overexpression vector,p BWA(V)HS-StLDC,was constructed.This vector was subsequently introduced into K326 tobacco via Agrobacteri-um-mediated transformation to elucidate the biological function of StLDC.Molecular and metabolic analyses of the ob-tained transgenic plants revealed that qRT-PCR confirmed the successful overexpression of StLDC in tobacco.High per-formance liquid chromatography-electrospray ionization-mass/mass spectrometry(HPLC-ESI-MS/MS)detection indi-cated that the contents of matrine and oxymatrine in transgenic plants were significantly higher than those in wild-type(WT)plants,with the highest matrine content reaching 29.11 times and the highest oxymatrine content reaching 69.43 times that of the WT.These results indicate that the StLDC gene can significantly increase the contents of matrine and oxymatrine in tobacco,providing important genetic resources for the cultivation of plants with high alkaloid content,espe-cially S.tonkinensis.