Liu Wen, Ghouri Fozia, Yu Hang, Li Xiang, Yu Shuhong, Shahid Muhammad Qasim, Liu Xiangdong
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China.
Department of Tropical Crops, Guangdong Agriculture Industry Business Polytechnic College, Guangzhou, China.
PLoS One. 2017 Jul 11;12(7):e0180662. doi: 10.1371/journal.pone.0180662. eCollection 2017.
Common wild rice (Oryza rufipogon Griff.) is an important germplasm for rice breeding, which contains many resistance genes. Re-sequencing provides an unprecedented opportunity to explore the abundant useful genes at whole genome level. Here, we identified the nucleotide-binding site leucine-rich repeat (NBS-LRR) encoding genes by re-sequencing of two wild rice lines (i.e. Huaye 1 and Huaye 2) that were developed from common wild rice. We obtained 128 to 147 million reads with approximately 32.5-fold coverage depth, and uniquely covered more than 89.6% (> = 1 fold) of reference genomes. Two wild rice lines showed high SNP (single-nucleotide polymorphisms) variation rate in 12 chromosomes against the reference genomes of Nipponbare (japonica cultivar) and 93-11 (indica cultivar). InDels (insertion/deletion polymorphisms) count-length distribution exhibited normal distribution in the two lines, and most of the InDels were ranged from -5 to 5 bp. With reference to the Nipponbare genome sequence, we detected a total of 1,209,308 SNPs, 161,117 InDels and 4,192 SVs (structural variations) in Huaye 1, and 1,387,959 SNPs, 180,226 InDels and 5,305 SVs in Huaye 2. A total of 44.9% and 46.9% genes exhibited sequence variations in two wild rice lines compared to the Nipponbare and 93-11 reference genomes, respectively. Analysis of NBS-LRR mutant candidate genes showed that they were mainly distributed on chromosome 11, and NBS domain was more conserved than LRR domain in both wild rice lines. NBS genes depicted higher levels of genetic diversity in Huaye 1 than that found in Huaye 2. Furthermore, protein-protein interaction analysis showed that NBS genes mostly interacted with the cytochrome C protein (Os05g0420600, Os01g0885000 and BGIOSGA038922), while some NBS genes interacted with heat shock protein, DNA-binding activity, Phosphoinositide 3-kinase and a coiled coil region. We explored abundant NBS-LRR encoding genes in two common wild rice lines through genome wide re-sequencing, which proved to be a useful tool to exploit elite NBS-LRR genes in wild rice. The data here provide a foundation for future work aimed at dissecting the genetic basis of disease resistance in rice, and the two wild rice lines will be useful germplasm for the molecular improvement of cultivated rice.
普通野生稻(Oryza rufipogon Griff.)是水稻育种的重要种质资源,含有许多抗性基因。重测序为在全基因组水平探索丰富的有用基因提供了前所未有的机会。在此,我们通过对由普通野生稻培育而来的两个野生稻品系(即华野1号和华野2号)进行重测序,鉴定出了编码核苷酸结合位点富含亮氨酸重复序列(NBS-LRR)的基因。我们获得了1.28亿至1.47亿条 reads,覆盖深度约为32.5倍,并且独特地覆盖了参考基因组的89.6%以上(>=1倍)。与日本晴(粳稻品种)和93-11(籼稻品种)的参考基因组相比,两个野生稻品系在12条染色体上显示出较高的单核苷酸多态性(SNP)变异率。插入/缺失多态性(InDels)的计数长度分布在两个品系中呈正态分布,并且大多数InDels的范围为-5至5 bp。参照日本晴基因组序列,我们在华野1号中总共检测到1,209,308个SNP、161,117个InDels和4,192个结构变异(SVs),在华野2号中检测到1,387,959个SNP、180,226个InDels和5,305个SVs。与日本晴和93-11参考基因组相比,两个野生稻品系中分别有44.9%和46.9%的基因表现出序列变异。对NBS-LRR突变候选基因的分析表明,它们主要分布在第11号染色体上,并且在两个野生稻品系中,NBS结构域比LRR结构域更保守。NBS基因在华野1号中表现出比华野2号更高水平的遗传多样性。此外,蛋白质-蛋白质相互作用分析表明,NBS基因大多与细胞色素C蛋白(Os05g0420600、Os01g0885000和BGIOSGA038922)相互作用,而一些NBS基因与热休克蛋白、DNA结合活性、磷酸肌醇3激酶和一个卷曲螺旋区域相互作用。我们通过全基因组重测序在两个普通野生稻品系中探索了丰富的NBS-LRR编码基因,这被证明是在野生稻中挖掘优良NBS-LRR基因的有用工具。这里的数据为未来旨在剖析水稻抗病遗传基础的工作提供了基础,并且这两个野生稻品系将是用于栽培稻分子改良的有用种质资源。