Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785 013, India.
Gene. 2012 Sep 10;506(1):202-6. doi: 10.1016/j.gene.2012.06.055. Epub 2012 Jul 1.
Tea is the most popular non-alcoholic and healthy beverage across the world. The understanding of the genetic organization and molecular biology of tea plant, which is very poorly understood at present, is required for quantum increase in productivity and efficient use of germplasm for either cultivation or breeding program. Single-pass sequencing of randomly selected cDNA clones is the most widely accepted technique for gene identification and cloning. In the present study, a good quality cDNA library was constructed and preliminary analysis of ESTs was carried out. The titers of unamplified and amplified libraries were 1.4 × 10(6)pfu/ml and 5.27 × 10(8)pfu/ml respectively. A total of 210 cDNA clones from the constructed cDNA library were sequenced and analyzed. A total of 84 high quality Expressed Sequence Tags (ESTs) were generated, among which 71 ESTs had significant homology with sequences in NCBI non-redundant protein database by BLAST X analysis. About 80% ESTs had poly (A) tail at 3' end indicating that the cDNAs were full length. The database-matched ESTs were classified into putative cellular roles, viz. energy-related category (corresponding to 20% of total BLAST X matched ESTs), Transcription (14.2%), protein synthesis (14.2%) cell growth and division (8.6%), cell structure (5.7%), signal transduction (5.7%), transporters (2.9%), disease and defenses (2.9%), secondary metabolism (2.9%) and gene regulation (2.9%). This study provides an overview of the mRNA expression profile and first hand information of gene sequence expressed in tender leaves and apical buds of tea plant.
茶是全球最受欢迎的非酒精性健康饮品。目前,人们对茶树的遗传组织和分子生物学了解甚少,这对于提高生产力和有效利用种质资源进行栽培或育种计划至关重要。随机选择 cDNA 克隆的单通测序是基因鉴定和克隆最广泛接受的技术。在本研究中,构建了一个高质量的 cDNA 文库,并对 ESTs 进行了初步分析。未扩增和扩增文库的滴度分别为 1.4×10^6 pfu/ml 和 5.27×10^8 pfu/ml。从构建的 cDNA 文库中随机测序和分析了 210 个 cDNA 克隆。共生成了 84 条高质量的表达序列标签(ESTs),其中 71 条 ESTs 通过 BLAST X 分析与 NCBI 非冗余蛋白质数据库中的序列具有显著同源性。约 80%的 ESTs 在 3'端具有多聚(A)尾,表明 cDNA 是全长的。与数据库匹配的 ESTs 被分类为推测的细胞功能,即能量相关类别(对应于总 BLAST X 匹配 ESTs 的 20%)、转录(14.2%)、蛋白质合成(14.2%)、细胞生长和分裂(8.6%)、细胞结构(5.7%)、信号转导(5.7%)、转运蛋白(2.9%)、疾病和防御(2.9%)、次生代谢(2.9%)和基因调控(2.9%)。本研究提供了茶树嫩叶和顶芽 mRNA 表达谱和基因序列表达的概述及第一手资料。