Reddy Arjula R, Ramakrishna W, Sekhar A Chandra, Ithal Nagabhushana, Babu P Ravindra, Bonaldo M F, Soares M B, Bennetzen Jeffrey L
Department of Plant Sciences, School of Life Sciences, University of Hyderabad, India.
Genome. 2002 Feb;45(1):204-11. doi: 10.1139/g01-114.
We have utilized an efficient method to enrich cDNA libraries for novel genes and genes responsive to drought stress in rice (Oryza sativa L. subsp. indica). We separately constructed standard and normalized cDNA libraries from leaf tissue of rice seedlings grown under controlled drought stress. Sequencing from the 3' end was performed on 1000 clones from the normalized leaf cDNA library and 200 clones from the standard leaf cDNA library. For the first 200 clones, the clone redundancy in the non-normalized library was about 10%, compared with 3.5% in the normalized cDNA library. Comparison of these cDNAs with the sequences in public databases revealed that 28.2% of the expressed sequence tags (ESTs) from the normalized library were novel. Clones from the standard and normalized leaf libraries and a root library uncovered numerous cDNAs that are highly homologous to known drought-responsive genes including those that encode metallothioneins, late embroyonic abundant (LEA) proteins, heat-shock proteins, cytochrome P450 enzymes, catalases, peroxidases, kinases, phosphatases, and transcription factors.
我们采用了一种高效方法，用于富集水稻（Oryza sativa L. subsp. indica）中新型基因和干旱胁迫响应基因的cDNA文库。我们分别从在可控干旱胁迫下生长的水稻幼苗叶片组织构建了标准cDNA文库和标准化cDNA文库。对标准化叶片cDNA文库中的1000个克隆和标准叶片cDNA文库中的200个克隆进行了3'端测序。对于前200个克隆，非标准化文库中的克隆冗余度约为10%，而标准化cDNA文库中的克隆冗余度为3.5%。将这些cDNA与公共数据库中的序列进行比较发现，标准化文库中28.2%的表达序列标签（EST）是新的。来自标准和标准化叶片文库以及一个根文库的克隆揭示了许多与已知干旱响应基因高度同源的cDNA，这些基因包括编码金属硫蛋白、胚胎后期丰富（LEA）蛋白、热休克蛋白、细胞色素P450酶、过氧化氢酶、过氧化物酶、激酶、磷酸酶和转录因子的基因。
