广藿香PcGA2ox1基因克隆、VIGS载体构建和表达分析OA北大核心CSTPCD

Gibberellin 2-oxidases(GA2ox)is a key enzyme in metabolic pathway of gibberellins(GAs),which regulates the degradation of active GAs and plays important roles in plant type regulation.In order to explore the function of GA2ox gene in Pogostemon cablin,we cloned PcGA2ox1 gene of P.cablin and obtained 561 bp of CDS sequence.The results of bioinformatics analysis showed that PcGA2ox1 protein enco-ded 186 amino acids,was a hydrophilic protein with the molecular weight as 20.98 kDa and the isoelectric point as 5.81,contained neither signal peptide nor transmembrane domain,had the conserved domain of GA2ox supergene family,and was mainly located in nucleus.Phylogenetic analysis showed that PcGA2ox1 was most closely related to Salvia miltiorrhiza GA2ox7.The qRT-PCR results showed that PcGA2ox1 gene had tis-sue-specific expression in P.cablin with the highest level in leaves and the lowest level in roots.Infestation of P.cablin by virus-induced gene silencing(VIGS)technology showed that PcGA2ox1 gene expression decreased by 83%compared with negative control and 71%compared with blank control two weeks later,and the silen-cing effect was obvious.The results of this study could lay a foundation for an in-depth understanding of the structure,function and mechanism of PcGA2ox1,and provide a reference for the selection and breeding of ex-cellent P.cablin varieties.