PNAS:武汉大学何光存实验室等发表水稻抗虫基因研究新进展
2016年10月25日,国际著名学术期刊《美国国家科学院院刊》杂志在线发表了武汉大学生命科学学院杂交水稻国家重点实验室何光存教授、陈荣智副教授研究团队与华中农业大学张启发院士研究组合作题为 “Allelic diversity in an NLR gene BPH9 enables rice to combat planthopper variation”的研究论文。博士生赵艳、黄锦和王志政是该论文第一作者，华中农大张启发院士、何光存教授和陈荣智副教授为论文共同通讯作者。
水稻是世界上最重要的粮食作物之一，褐飞虱是随水稻而生专门取食水稻的害虫。在自然界中，为了抵抗褐飞虱取食，水稻进化出了抗虫性;而褐飞虱则形成能克服水稻抗性的生物型群体，水稻反过来又产生出新的抗性来对抗褐飞虱。如此周而复始，二者形成协同进化关系，使得在传统农业中褐飞虱不会对水稻造成重大危害。该研究团队与华中农大张启发院士等国内外同行合作，克隆了水稻第12染色体长臂上的一个抗褐飞虱基因BPH9，并发现此前定位在该染色体区段上的7个抗褐飞虱基因均是BPH9的等位基因。正是由于BPH9的等位变异使得水稻可以抵抗褐飞虱不同生物型群体，因此揭示了抗虫基因等位变异是水稻应对褐飞虱种群变异的重要策略。该论文还分析了BPH9基因在水稻群体中分化和演化特点。基于BPH9等位型在野生稻和栽培稻中的分布，发现人类抗虫育种实践重演了自然选择进化过程，即等位型1是在野生稻中最早出现的抗虫等位型，也是第一个应用于现代抗虫育种的等位型，随后是等位型2。等位型7和等位型9则是新近发掘的等位型，对三种生物型的褐飞虱均表现为抗性，在今后的水稻抗虫育种中具有重要利用价值。
原文链接：
Allelic diversity in an NLR gene BPH9 enables rice to combat planthopper variation
原文摘要：
Brown planthopper (BPH), Nilaparvata lugens Stål, is one of the most devastating insect pests of rice (Oryza sativa L.). Currently, 30 BPH-resistance genes have been genetically defined, most of which are clustered on specific chromosome regions. Here, we describe molecular cloning and characterization of a BPH-resistance gene, BPH9, mapped on the long arm of rice chromosome 12 (12L). BPH9 encodes a rare type of nucleotide-binding and leucine-rich repeat (NLR)-containing protein that localizes to the endomembrane system and causes a cell death phenotype. BPH9 activates salicylic acid- and jasmonic acid-signaling pathways in rice plants and confers both antixenosis and antibiosis to BPH. We further demonstrated that the eight BPH-resistance genes that are clustered on chromosome 12L, including the widely used BPH1, are allelic with each other. To honor the priority in the literature, we thus designated this locus as BPH1/9. These eight genes can be classified into four allelotypes, BPH1/9-1, -2, -7, and -9. These allelotypes confer varying levels of resistance to different biotypes of BPH. The coding region of BPH1/9 shows a high level of diversity in rice germplasm. Homologous fragments of the nucleotide-binding (NB) and leucine-rich repeat (LRR) domains exist, which might have served as a repository for generating allele diversity. Our findings reveal a rice plant strategy for modifying the genetic information to gain the upper hand in the struggle against insect herbivores. Further exploration of natural allelic variation and artificial shuffling within this gene may allow breeding to be tailored to control emerging biotypes of BPH.
作者：何光存和陈荣智
