资阳香橙根cDNA全长文库的构建及EST分析

Construction of a Full-length cDNA Library from Roots of Ziyang Xiangcheng(Citrus junos) and a Catalogue of the Expressed Sequence Tags in Roots

以资阳香橙根RNA为材料，采用趴压ART技术构建了cDNA全长文库，并对其质量进行鉴定。结果显示，该文库的库容量为4．8×10。pfu／mL，重组率为93％，文库插入片段大小主要集中在0．5～1．0kb。从文库中随机挑取450个克隆进行5’端单向测序，去除载体序列及低质量的序列后，共获得有效长度大于150bp的高质量ESTs（expressed sequence tags）序列438条，利用Bi-oEdit软件对有效ESTS序列进行片段重叠群分析和拼接后，获得251个独立基因（Unigenes），其中包括87个片段重叠群（Contigs）和164个独立的ESTs（Singlets）；通过与NCBI的非冗余核酸数据库进行tBLASTx比对，初步确定已知功能基因146个，未知功能基因91个．另有14个umgene未与数据库中序列匹配。该研兜为进一步分离克隆资阳香橙根部功能基因奠定了基础。

A full-length eDNA library was constructed from the root tissues of Ziyang Xiangeheng （Citrus junos ） by using SMART technology and the quality of the library was evaluated. The results showed that the titer of the library was 4.8 X 105 pfu · mL^-1 with a reco/nbination rate of 93%. The insert sizes of the library were between 0. 5 and 1.0 kb. Four hundred and fifty clones were randomly sequenced from the 5’-terminals of the inserts and 438 expressed sequence tags were thus obtained. Contigs were assembled using BioEdit software and a total of 251 unigenes were finally obtained. These unigenes ihcluded 87 contigs and 164 singlets. A tBLASTx search against NCBI non-redundant nucleic acid database identified 146 genes with known functions, 91 without known functions, and 14 without a match in the database. The results should facilitate the cloning and functional analysis of genes from the roots of Ziyang junos.