摘要
为研究甘薯sporamin家族基因的结构和功能,通过对本实验室构建的甘薯转录组序列进行分析,设计相应引物并采用高保真DNA聚合酶进行PCR扩增,经TA克隆和序列测定,利用在线软件对甘薯sporamin结构进行分析和功能预测.从转录组数据库中共发现61条sporamin contigs,其中sporamin A家族有31条,sporamin B家族有30条,已从甘薯中克隆到6个sporamin A基因和10个sporamin B基因.所有sporamin A基因编码区全长660 bp,基因间序列一致性为95%以上;sporamin B基因编码区全长651 bp,基因间序列一致性达到98%;两个基因家族间序列一致性为84%.对克隆的sporamin A和sporamin B进行的数字表达谱分析结果表明,sporamin A和B在膨大初期的块根和成熟块根中的转录水平最高,在膨大中期转录水平较低,在叶片和茎中表达量极低.Sporamin氨基酸保守序列和同源比对结果显示,该蛋白质含有STI(Soybean Trypsin Inhibitor)保守序列,此序列有170多个氨基酸,属于Kunitz型蛋白酶抑制剂超家族,表明该蛋白具有蛋白酶抑制剂功能.
In order to study the structure and function of sporamin family genes in sweet potato, the transcriptome database of this plant constructed in our lab were analyzed to screen sporamin contigs and appropriate primers designed to amplify sporamin genes, which were then cloned and sequenced. All together 61 sporamin contigs were found in the transcriptome database, including 31 contigs in sporamin A sub-family and 30 contigs in sporamin B sub-family. Six sporamin A genes and 10 sporamin B genes were cloned and sequenced. ORF of all sporamin A genes were 660 bp in length with identity more than 95% among all sporamin A genes. ORF of sporamin B genes had a total length of 651 bp with identity more than 98% among sporamin B genes. Homology between the two sub-families was 84%. The results of digital gene expression profile analysis showed that both sporamin A and B had the highest level of transcription in the initial tuberous roots and harvest tuberous roots, comparatively low transcription in the expanding tuberous roots, and very little in leaves and stems. Analysis of conserved sequence of sporamin genes and homology comparison displayed that the proteins contained a soybean trypsin inhibitor conserved sequence with more than 170 amino acids belonging to the Kunitz-type protease inhibitor superfamily, indicating that the sporamin has the function of protease inhibitors. Fig 9, Tab 3, Ref 33
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2013年第2期215-223,共9页
Chinese Journal of Applied and Environmental Biology
基金
国家科技支撑计划项目(2007BAD78B03)
四川省“十一五”重点科技攻关项目(07SG111-003-1)资助~~
关键词
甘薯
储藏蛋白
基因克隆
序列分析
数字基因表达谱
蛋白酶抑制剂
sweet potato
sporamin
gene cloning
sequence analysis
digital gene expression profiling
protease inhibitor
