马尾松苯丙氨酸解氨酶基因cDNA全长克隆与序列分析

Cloning and Sequence Analysis of Full-Length cDNA of Phenylalanine Ammonia-Lyase of Pinus Massoniana

苯丙氨酸解氨酶(Phenylalanine ammonia-lyase,PAL)是连接植物初级代谢和次级代谢途径关键酶、限速酶,催化苯丙氨酸转化为肉桂酸,促进黄酮、木质素等次生代谢产物的合成,在植物抗病过程中有重要意义.采用RT-PCR和RACE技术,从马尾松中克隆到PAL基因的cDNA全长.此cDNA全长2 700 bp,包括2 154 bp的完整ORF,编码717个氨基酸的蛋白,相对分子质量与等电点分别为78 200和5.81.其推导的蛋白序列与火炬松(Pinustaeda)、欧洲赤松(Pinus sylvestris)和海岸松(Pinus pinaster)的苯丙氨酸解氨酶同源性分别为98.2%、99.4%和97.8%.

Phenylalanine ammonia-lyase（PAL） is the key enzyme and rate-limiting enzyme that linked primary metabolism to secondary metabolism and plays a crucial role in disease resistance.It catalyzes phenylalanine ammonia into β-phenylacrylic acid and improves the synthesization of flavone and lignose.The full-length cDNA of phenylalanine ammonia-lyase was obtained by RT-PCR and RACE from Pinus massoniana.It consists of 2 700 nucleotides,with a 2 154 bp open read frame and encodes a protein of 717 amino acids.The theoretical molecular weight of the putative protein was 78 200 and the pI was 5.81.Phylogenetic analysis indicated that,compared with PAL homologous proteins from Pinus taeda,Pinus sylvestris and Pinus pinaster,the amino acid sequence identities were 98.2%、99.4% and 97.8% respectively.