橡胶树炭疽病菌Cap20基因的克隆和序列分析

摘要

根据鳄梨胶孢炭疽菌Cap20基因序列设计引物,利用同源基因克隆法获得橡胶树胶孢炭疽菌和尖孢炭疽菌Cap20基因,同时进行核苷酸序列、氨基酸序列及聚类分析.结果表明:2种橡胶树炭疽菌的Cap20基因均含2个外显子和1个内含子,编码183个氨基酸；橡胶树胶孢炭疽菌与鳄梨胶孢炭疽菌同源性最高,其核苷酸序列同源性达90.3％,氨基酸序列同源性达98.9％；来自橡胶树的2种炭疽菌Cap20基因序列存在较大差异,其核苷酸水平同源性仅为73.8％,氨基酸水平同源性为79.8％；炭疽菌CAP20和绿僵菌MPL1蛋白结构具有42％的同源性,所含蛋白结构域相似,推测炭疽菌Cap20基因可能与绿僵菌Mpl1基因功能具有相似性.%In this study, the primers were designed according to the Cap20 gene sequences in NCBI database. DNA and cDNA sequences of Cap20 from the two pathogens causing Leaf disease of rubber tree were amplified by polymerase Chain Reaction and Reverse Transcription Polymerase Chain Reaction, and then the amplification products were sequenced and aligned with the other 3 Colletotrichum species Cap20 gene sequences. The results showed that the full open reading frames of Cap20 gene of 2 species from rubber tree contained 2 exons and 1 intron, and encoded a protein of 183 amino acids; Cap20 genes from the same species of C. gloeosporioides of the rubber tree and avocado showed 90.3% similarity in nucleotide and 98.9% similarity in amino acid; The gene from 2 Colletotrichum species of rubber tree showed more difference in nucleotide (73.8%) and amino acid sequences (79.8%). The study also made out that CAP20 protein showed homology to a reputed MPL1 protein, which regulated lipid metabolism, appressorial turgor pressure and virulence in Metarhizium anisopliae.