黑豆NBS类抗病基因同源片段的克隆与分析

根据已克隆的抗病基因保守结构域设计简并引物，以湖南黑豆（HH）为试材，通过RT-PCR，从cDNA中扩增抗病基因同源序列，测序鉴定出2个含有通读阅读框的DNA片段：FNBSl、FNBS3。FNBS1大小为534bp，编码178个氨基酸；FNBS3大小为513bp，编码169个氨基酸。BLASTP分析表明，2个片段均具有NB-ARC结构域（与植物抗病有关），并且包含p-loop、Kinase-2、HD等结构域。基因FNBSl与大豆基因RPMl-like编码的氨基酸序列的同源性为98％，基因FNBS3与大豆基因N-like 编码的氨基酸序列的同源性为99％，推测FNBS1、FNBS3可能是黑豆NBS-LRR类抗病基因的核心区域。

Cloning and Sequence Analysis of NBS Type Resistant Gene Analogues in Black Soybean

Degenerate primers based on conserved sequences of the nucleotide binding site （NBS）region from the cloned plant disease resistant genes were used to isolate resistant gene analogues （RGAs） from cDNA of black soybean.Two RGAs of black soybean were obtained, and were named FNBS1 and FNBS3.The length of FNBS1 was 534 bp,encoded 178 amino acids.FNBS3 had 513 bp in length,encoded 169 amino acids.BLASTP analysis indicated that two RGAs contained the conserved motifs of NB-ARC （such as P-loop, Kinase2et, Kinase3ct and HD domain）.Homology analysis showed that amino acid sequence of FNBS1 gene had highly homology with the reported resistant gene RPM1-like, amino acid sequence of FNBS3 gene had highly homology with the reported resistant gene N-like.The analysis of RGAs amino acid sequence structures suggested that FNBS1 and FNBS3 were the core region of NBS-LRR resistant genes in black soybean.