(E)-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of (E)-β-caryophyllene synthase in lima bean ...(E)-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of (E)-β-caryophyllene synthase in lima bean (Phaseolus lunatus). Here, we report a new full-length cDNA (PICAHS) encoding (E)-β-caryophyllene synthase, a possible key enzyme of plant defence. The cDNA of PICAHS contains an open reading frame of 1 761 bp, encoding a protein of 586 amino acids with a predicted mass of 67.95 kDa. The deduced amino acid sequence shows 52% identity with sesquiterpene synthase MtCAHS of Med- icago truncatula. Based on phylogenetic analysis, PICAHS is classified as the terpene synthases (TPS)-a subfamily. The recombinant enzyme, expressed in Escherichia coil, catalysed the formation of a major product (E)-β-caryophyllene (82%) and a minor product a-humulene (18%) from farnesyl dJphosphate. Real-time quantitative PCR (qRT-PCR) analysis found that the PICAHS transcript was significantly up-regulated in leaves after treatment with spider mites and alamethicin (ALA), suggesting its ecological function in plant defence.展开更多
基金funded by the International Science and Technology Cooperation Program of China (2013DFG32230)the Major Project of Genetically Modified Organisms Breeding,China (2016ZX08010005)
文摘(E)-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of (E)-β-caryophyllene synthase in lima bean (Phaseolus lunatus). Here, we report a new full-length cDNA (PICAHS) encoding (E)-β-caryophyllene synthase, a possible key enzyme of plant defence. The cDNA of PICAHS contains an open reading frame of 1 761 bp, encoding a protein of 586 amino acids with a predicted mass of 67.95 kDa. The deduced amino acid sequence shows 52% identity with sesquiterpene synthase MtCAHS of Med- icago truncatula. Based on phylogenetic analysis, PICAHS is classified as the terpene synthases (TPS)-a subfamily. The recombinant enzyme, expressed in Escherichia coil, catalysed the formation of a major product (E)-β-caryophyllene (82%) and a minor product a-humulene (18%) from farnesyl dJphosphate. Real-time quantitative PCR (qRT-PCR) analysis found that the PICAHS transcript was significantly up-regulated in leaves after treatment with spider mites and alamethicin (ALA), suggesting its ecological function in plant defence.