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NBS(nucleotide binding site)genes,one type of the most important disease resistance genes in the plant kingdom,are usually found clustered in genome.In this study,a total of 2288 full-length/complete NBS protein sequences with genomic locations were isolated from the bread wheat(Triticum aestivum L.)genome using bioinformatics tools,which were composed of four subgroups N(NBS),CN(CC-NBS),NL(NBS-LRR)and CNL(CC-NBS-LRR).Out of these sequences,903 TaNBS were found expressed in wheat leaves.Meanwhile,2203 microsatellite loci were detected within 1061 scaffolds containing TaNBS,and 1621 of which were dinucleotide microsatellites/repeats loci,accounting for 73.6%.The distribution of these microsatellite loci across wheat homologous groups(HG)is 20%HG2,16%HG7,15%HG1,15%HG6,12%HG4,12%HG5 and 10%HG3.We developed at least one pair of markers for every TaNBS-scaffold possessing microsatellite loci and 1301 pairs of NBS-related microsatellite(NRM)markers were developed.Among them,342 NRM markers were developed for HG2 with the largest number of microsatellite loci,and 69 out of these NRM markers were anchored to the wheat genetic map using the RIL F9 population derived from a cross between CH7034 and SY95-71.The NRM markers were then employed for fine mapping,and a total of twenty-six 2AS-NRM markers,nine 2BL-NRM markers and nine 2DL-NRM markers were integrated into the genetic maps harboring/carrying Yr69,Pm51 and Pm43,respectively.Finally,candidate sequences,within the gene clusters where Yr5 and Sr21located,were analyzed according to the genomic position information of TaNBS and NRM markers.NRM markers,developed in this study,have clear chromosome locations and are correlated with disease resistance sequences,which can be manipulated to anchor or fine mapping disease resistance genes or QTLs,especially for those in the NBS gene clusters.Moreover,those isolated TaNBS sequences could provide reference for homologous cloning or map-based cloning.