中文摘要：

利用BLAST（basic local alignment search tool）和HMM（hidden markov model）工具,对蒺藜苜蓿（Medicago truncatula）全基因组Mt2.0数据中含有核苷酸结合位点（NBS）结构的抗病基因进行了分析,包括NBS基因数量、类型、基因复制、物理位置分析和系统进化树关系分析。结果表明,在苜蓿全基因组中找到469个含有NBS结构的抗病基因,其中包括446个标准结构NBS基因、23个非标准结构NBS基因。通过对全基因组内标准NBS类型抗病基因进行物理位置和基因家族分析,发现苜蓿基因组中抗病基因存在明显的基因复制现象,基因的复制对苜蓿基因组中NBS类型抗病基因数量扩张起到了重要的作用。

英文摘要：

By BLAST（basic local alignment search tool） and HMM（hidden markov model） analyses, a complete set of disease resistance candidate genes encoding nucleotide-binding-sites （NBS） was identified in a complete genome（Mt2.0） of Medicago truncatula and these putative R genes were characterized with respect to structural diversity, gene duplication, physical positions and phylogenet- ic relationships. The results showed that 469 NBS-coding sequences, which contained 446 regular NBS genes and 23 non-regular NBS genes, were found in the complete genome. By NBS standard physical locations and gene families analyses, significant excesses of gene duplications which played a major role for the expansion of disease resistance genes were found in the whole genome of Medicago truncatula.