Discovery and analysis of NBS-LRR gene family in sweet potato genome

Abstract

<p indent=0mm>The NBS-LRR gene families possess the most abundant resistance genes in plants. Members of the NBS-LRR gene families contain nucleotide-binding site (NBS) and leucine-leucine repeat (LRR) domains. The genome of sweet potato (<italic>Ipomoea batatas</italic>) cultivar has been sequenced but the genes have not been annotated yet. In this study, we predicted the exons of sweet potato genome and obtained the proteins sequences, which were then used to identify and analyze genes of NBS-LRR family. There were 379 genes within NBS-LRR family, amounting to 0.212% of the total genes of sweet potato. The number of the N type, NL type, CNL type, TNL type and PN type was 120, 103, 133, 22, and 1, respectively. All of the chromosomes had NBS-LRR family genes but varied in number and 60.9% of them were clustered. NBS-LRR genes included 15 conservative domains and the genes were conservative within N terminal domain. The results provide references for further studies on the function of NBS-LRR family genes and resistance breeding of sweet potato.