[关键词]
[摘要]
目的 构建千里光全长cDNA文库,以期研究千里光的功能基因组学信息,为克隆药理学性状相关的功能基因提供数据资源。方法 Trizol法提取千里光叶片总RNA,通过SMART(switching mechanism at 5’ end of RNA transcript)构建全长cDNA文库,随机挑取600个单克隆测序分析文库滴度、全长率及冗余率,得到的EST序列进行Blast分析(NR、NT、Swiss-Prot、KEGG)及COG功能分类。结果 文库的库容为4.3×106 cfu/mL,插入片段大小平均1.7 kb,文库重组率96.35%,全长率58.24%,冗余率10.88%;获得524条全长EST序列,含有467条独立基因(unigenes),其中5条序列与千里光次生代谢产物的合成、运输与代谢有关。结论 经检测,SMART技术成功构建了千里光全长cDNA文库,该文库可用于千里光功能基因组鉴定、新基因筛选及次生代谢产物生物合成的表达调控研究。
[Key word]
[Abstract]
Objective In the present study, our information from Senecio scandens full-length cDNA clones will serve as a useful resource for elucidating functional genes and will also aid a precise annotation of genomics in Compositae plants. Methods The total RNA was extracted from S. scandens using Trizol method. SMART (switching mechanism at 5’ end of RNA transcript) was applied to constructing the full-length cDNA library. Titer of the library, full-length ratio, and redundancy rate for 600 monoclone randomly selected sequencing library were evaluated by PCR amplification. NCBI and COG database was used to compare those sequences. Results Parameters of the the quality of cDNA library were as follows: the capacity of the library (4.3×106 cfu/mL), the average size of the inserted fragment (1.7 kb), the recombination rate (96.35%), the full-length rate (58.24%), and the redundancy rate (10.88%). EST sequences for 524 full-length were obtained in this study, involving 467 unigenes, among which five sequences associated with synthesis, transport, and metabolism of S. scandens secondary metabolites. Conclusion SMART technology could be effectively applied to constructing the full-length cDNA library of S. scandens. Our results indicate that the full-length cDNA library could be further applied to regulation of expression on identification of functional genome, screening of novel genes, and biosynthesis of metabolism genes in S. scandens.
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[基金项目]
贵州省优秀科技教育人才省长基金项目(黔省专合字2008-61号)