Disease resistance and sexual reproductive development are generally considered as separate biological processes, regulated by different sets of genes. Here we show that xa13, a recessive allele conferring disease resistance against bacterial blight, one of the most devastating rice diseases worldwide, plays a key role in both disease resistance and pollen development. The dominant allele,Xa13, is required for both bacterial growth and pollen development. Promoter mutations in Xa13 cause down-regulation of expression during host–pathogen interaction, resulting in the fully recessive xa13 that confers race-specific resistance. The recessive xa13 allele represents a new type of plant disease resistance.
通常認(rèn)為抗病性與性生殖發(fā)育是兩個(gè)獨(dú)立的生理過(guò)程，由不同系列的基因調(diào)控。本文我們發(fā)現(xiàn)一個(gè)抗白葉枯病隱性等位基因，xa13，白葉枯病是世界范圍內(nèi)最具毀滅性的水稻病害之一，xa13在抗病性和花粉發(fā)育過(guò)程中均發(fā)揮關(guān)鍵作用。細(xì)菌生長(zhǎng)和花粉發(fā)育均需要Xa13顯性等位基因。在宿主和病原菌相互作用時(shí)，Xa13啟動(dòng)子突變會(huì)引起它自身表達(dá)的下調(diào)，產(chǎn)生完全隱性xa13，進(jìn)而賦予水稻小種特異抗性。隱性xa13等位基因代表了水稻抗病性的一種新類型。