论文部分内容阅读
根据大多数抗病基因的核苷酸结合区(NBS)和富含亮氨酸重复序列(LRR)保守区的氨基酸序列设计PCR简并引物,利用快速而又可行的简并PCR技术获得NBS-LRR类抗病基因类似序列。笔者利用该技术从香蕉cDNA中获得了一个NBS-LRR类抗病基因类似序列,命名为B-NB(SAY739270)。结构域分析发现,B-NBS含有NBS蛋白所具有的P-Loop、Kinase-2、Kinase-3a和下游疏水GLPLAL结构域(HD,GLPLAL)4个保守基序。聚类分析发现,B-NBS与已报道的6个植物抗病基因的NBS基序的遗传距离在21.7之内。因此,B-NBS是一个香蕉NBS-LRR类抗病基因类似序列。本研究将为香蕉抗病基因克隆和抗病机理研究提供新的抗病候选基因资源。
PCR degenerate primers were designed based on the amino acid sequences of the nucleotide binding region (NBS) and the conserved region of leucine-rich repeats (LRR) of most disease-resistance genes. The rapid and feasible degenerate PCR technique was used to obtain NBS- LRR-like resistance genes similar sequences. Using this technique, we obtained a similar sequence of the NBS-LRR resistance gene from banana cDNA, named B-NB (SAY739270). Domain analysis showed that B-NBS contained four conserved motifs of P-Loop, Kinase-2, Kinase-3a and HDGLGLAL domain downstream of NBS protein (HD, GLPLAL). Cluster analysis showed that the genetic distance between B-NBS and reported NBS motifs of six plant disease-resistance genes was within 21.7. Therefore, B-NBS is a banana NBS-LRR resistance gene similar sequence. This study will provide new resistance candidate genes for the research on the cloning and disease resistance mechanism of banana disease resistance genes.