華中農(nóng)業(yè)大學(xué)科研人員日前成功分離出一個(gè)對(duì)水稻抗旱改良有顯著作用的基因OsSKIPa,。科研人員研究表明,，提高此基因在植物體內(nèi)表達(dá)水平可以顯著提高水稻抗旱性,，缺水的戈壁灘今后也將可能種植水稻。
此項(xiàng)成果近日發(fā)表在國(guó)際權(quán)威學(xué)術(shù)雜志美國(guó)《國(guó)家科學(xué)院院刊》(PNAS)上,。文章通訊作者為華中農(nóng)業(yè)大學(xué)生命科學(xué)技術(shù)學(xué)院熊立仲教授,，第一作者為該院研究生侯昕。熊立仲為該校國(guó)家水稻創(chuàng)新團(tuán)隊(duì)成員,，主要從事“抗逆基因的功能鑒定與利用”研究。
熊立仲教授介紹說(shuō),，OsSKIPa基因是通過(guò)基因芯片技術(shù)和轉(zhuǎn)基因技術(shù)篩選得到的眾多候選基因中的一個(gè),。實(shí)驗(yàn)顯示，在干旱條件下,，對(duì)照組水稻幼苗的存活率為百分之二十至百分之五十,，轉(zhuǎn)入OsSKIPa基因的實(shí)驗(yàn)組幼苗的存活率為百分之八十以上,；在成熟期，實(shí)驗(yàn)組的產(chǎn)量和結(jié)實(shí)率比對(duì)照組提高了百分之二十左右,。
該研究表明,，OsSKIPa基因會(huì)調(diào)動(dòng)其它水稻抗旱基因的表達(dá)，從而增強(qiáng)水稻細(xì)胞的活力,，提高水稻在缺水條件下的生存能力,，降低干旱引起的產(chǎn)量損失。這種類似觸發(fā)鏈?zhǔn)椒磻?yīng)的獨(dú)特作用機(jī)制以前從未在水稻研究中發(fā)現(xiàn)過(guò),。進(jìn)一步研究還表明,，水稻、人和酵母三類生物中的SKIP(OsSKIPa的同源基因)蛋白具有完全不同結(jié)合蛋白,，這種唯一性和特異性對(duì)基因進(jìn)化和新抗旱基因的發(fā)掘具有重要意義,。
熊立仲表示，水稻抗旱作用是眾多抗旱基因共同表達(dá)的結(jié)果,。此項(xiàng)成果是利用反向遺傳學(xué)的方法初步鑒定出了水稻抗逆性相關(guān)基因OsSKIPa的功能,，加深了對(duì)水稻抗逆分子機(jī)制的了解。同時(shí),，該基因的發(fā)現(xiàn)也對(duì)抗逆分子育種改良水稻品種有著重要的潛在價(jià)值,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS April 1, 2009, doi: 10.1073/pnas.0901940106
A homolog of human ski-interacting protein in rice positively regulates cell viability and stress tolerance
Xin Hou, Kabin Xie, Jialing Yao, Zhuyun Qi and Lizhong Xiong
Abiotic stresses are major limiting factors for growth, development, and productivity of crop plants. Here, we report on OsSKIPa, a rice homolog of human Ski-interacting protein (SKIP) that can complement the lethal defect of the knockout mutant of SKIP homolog in yeast and positively modulate cell viability and stress tolerance of rice. Suppression of OsSKIPa in rice resulted in growth arrest and reduced cell viability. The expression OsSKIPa is induced by various abiotic stresses and phytohormone treatments. Transgenic rice overexpressing OsSKIPa exhibited significantly improved growth performance in the medium containing stress agents (abscisic acid, salt, or mannitol) and drought resistance at both the seedling and reproductive stages. The OsSKIPa-overexpressing rice showed significantly increased reactive oxygen species-scavenging ability and transcript levels of many stress-related genes, including SNAC1 and rice homologs of CBF2, PP2C, and RD22, under drought stress conditions. More than 30 OsSKIPa-interacting proteins were identified, but most of these proteins have no matches with the reported SKIP-interacting proteins in animals and yeast. Together, these data suggest that OsSKIPa has evolved a specific function in positive modulation of stress resistance through transcriptional regulation of diverse stress-related genes in rice.
