玉米类受体激酶基因Psy2的生物信息学分析及RNAi转基因表达鉴定  

Bioinformatic Analysis and Transgenic RNAi Expression Identification of Maize Receptor-Like Kinase Gene Psy2

作　　者：吴晓军[1] 徐丽[1] 王守才[1] 

机构地区：[1]中国农业大学/国家玉米改良中心,北京100193

出　　处：《玉米科学》2015年第1期26-32,共7页Journal of Maize Sciences

基　　金：国家高新技术研究与发展计划"863"(2012AA101104;2011AA10A103);国家重点基础研究发展计划"973"(2009CB118400)

摘　　要：根据玉米细菌性褐斑病抗病基因的定位结果预测得到1个编码受体激酶(Receptor-like kinases,RLKs)基因Psy2,采用生物信息学方法对显性基因Psy2和隐性基因psy2编码蛋白的结构、功能和理化性质进行预测和分析。结果表明,psy2的编码氨基酸与Psy2相比共有57个氨基酸差异,包括起始密码子Met提前1位、1个精氨酸的缺失和55个氨基酸替换;两者理化性质差异较小,都被归类为不稳定蛋白;都具有信号肽,属分泌性蛋白;psy2无法形成有效跨膜结构域(Transmembrane domain,TM),但都定位于质膜;Psy2基因的进化与相应的物种进化相一致。推测psy2蛋白的氨基酸残基替换、缺失以及跨膜结构域的改变影响了信号的正常传导。通过基因枪转化法将RNA干扰表达载体导入受体HiⅡA×HiⅡB的幼胚,获得阳性转基因植株,经过q RT-PCR检测显示,Psy2a-RNAi在成株期(开花期)的干扰效果比苗期显著增强。A candidate gene Psy2 encoding receptor-like kinase was predicted based on the mapping results of maize bacterial brown spot disease. Bioinformatic analysis showed that 57 amino acid differences exist between Psy2 and psy2 proteins, including the changed position of initiation codon met, an amino acid deletion and 55 amino acid substitutions in psy2 protein. Psy2 and psy2 proteins were classified as unstable proteins, had a signal peptide, were secretory protein; psy2 protein unable to form an effective transmembrane domain（TM）, but both were located in the plasma membrane. The genetic evolution of psy2 proteinsis coincided with the evolution of corresponding species. Therefore, these amino acid changes in psy2 protein resulted in the abnormal function. The RNA interference expression vector was transformed into the immature embryos of HiⅡA×HiⅡB via particle bombardment, and the expression detection of transgenic plants by qRT-PCR showed that interference effects in the flowering period than seedling in Psy2a-RNAi plants significantly enhanced.

关 键 词：玉米 RNA干扰 转基因 细菌性褐斑病 

分 类 号：S513.035[农业科学—作物学]