An urgent need exists to identify more brown planthopper (Nilaparvata lugens Stål, BPH) resistance genes, which will allow the development of rice varieties with resistance to BPH to counteract the increased incidence of this pest species. Here, using bioinformatics and DNA sequencing approaches, we identified a novel BPH resistance gene, LOC_Os06g03240 (MSU LOCUS ID), from the rice variety Ptb33 in the interval between the markers RM19291 and RM8072 on the short arm of chromosome 6, where a gene for resistance to BPH was mapped by Jirapong Jairin et al. and renamed as “Bph32”. This gene encodes a unique short consensus repeat (SCR) domain protein. Sequence comparison revealed that the Bph32 gene shares 100% sequence identity with its allele in Oryza latifolia. The transgenic introgression of Bph32 into a susceptible rice variety significantly improved resistance to BPH. Expression analysis revealed that Bph32 was highly expressed in the leaf sheaths, where BPH primarily settles and feeds, at 2 and 24 h after BPH infestation, suggesting that Bph32 may inhibit feeding in BPH. Western blotting revealed the presence of Pph (Ptb33) and Tph (TN1) proteins using a Penta-His antibody, and both proteins were insoluble. This study provides information regarding a valuable gene for rice defence against insect pests.
目前急切需要鑒定更多的褐飛虱（BPH）抗性基因，這樣能夠培育具有褐飛虱抗性的水稻品種，抵御這種害蟲種類發(fā)病率的增加。本文，利用生物信息和DNA測序的方法，我們從水稻品種Ptb33中鑒定了一個新的BPH抗性基因，LOC_Os06g03240 (MSU LOCUS ID)，將它定位在6號染色體短臂端上分子標記RM19291和RM8072之間的區(qū)域內(nèi)，這里有一個之前由Jirapong Jairin等定位的BPH抗性基因，將它重新命名為Bph32。這個基因編碼一個獨特的短串聯(lián)重復（SCR）結(jié)構(gòu)域蛋白，序列比對表明，Bph32基因與它在闊葉稻中的等位基因具有100%的序列一致性。將Bph32轉(zhuǎn)基因滲入到一個感病水稻品種中能夠顯著提高對BPH的抗性。表達分析表明，在BPH侵染2h和24h后，Bph32在葉鞘高度表達，這是BPH飛落和取食的主要部位，表明Bph32主要抑制BPH的取食。利用Penta-His抗體進行免疫印跡分析表明，Pph（Ptb33）和Tph（TN1）蛋白的存在，并且這兩個蛋白是不可溶的。這項研究為評定水稻防衛(wèi)反應中抵御害蟲的一個有價值基因提供了信息。