华中农业大学科研人员日前成功分离出一个对水稻抗旱改良有显著作用的基因OsSKIPa。科研人员研究表明，提高此基因在植物体内表达水平可以显著提高水稻抗旱性，缺水的戈壁滩今后也将可能种植水稻。
此项成果近日发表在国际权威学术杂志美国《国家科学院院刊》(PNAS)上。文章通讯作者为华中农业大学生命科学技术学院熊立仲教授，第一作者为该院研究生侯昕。熊立仲为该校国家水稻创新团队成员，主要从事“抗逆基因的功能鉴定与利用”研究。
熊立仲教授介绍说，OsSKIPa基因是通过基因芯片技术和转基因技术筛选得到的众多候选基因中的一个。实验显示，在干旱条件下，对照组水稻幼苗的存活率为百分之二十至百分之五十，转入OsSKIPa基因的实验组幼苗的存活率为百分之八十以上；在成熟期，实验组的产量和结实率比对照组提高了百分之二十左右。
该研究表明，OsSKIPa基因会调动其它水稻抗旱基因的表达，从而增强水稻细胞的活力，提高水稻在缺水条件下的生存能力，降低干旱引起的产量损失。这种类似触发链式反应的独特作用机制以前从未在水稻研究中发现过。进一步研究还表明，水稻、人和酵母三类生物中的SKIP(OsSKIPa的同源基因)蛋白具有完全不同结合蛋白，这种唯一性和特异性对基因进化和新抗旱基因的发掘具有重要意义。
熊立仲表示，水稻抗旱作用是众多抗旱基因共同表达的结果。此项成果是利用反向遗传学的方法初步鉴定出了水稻抗逆性相关基因OsSKIPa的功能，加深了对水稻抗逆分子机制的了解。同时，该基因的发现也对抗逆分子育种改良水稻品种有着重要的潜在价值。（生物谷Bioon.com）
生物谷推荐原始出处：
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.
