枣抑制消减cDNA文库构建与分析

Construction and analysis of suppression subtractive cDNA library in Chinese date(Ziziphus jujube)

枣树具有独特的开花结果特性，为获得枣花发育基因，以金丝4号枣不同发育时期的花蕾和同时期的叶片cDNA互为试验方和驱动方，利用抑制消减杂交技术分别构建了枣花和枣叶抑制消减杂交cDNA文库（SSH文库）。枣花和枣叶SSH文库重组率分别是92．05％和90．26％，插入片段长度均介于200～2000bp之间，主要集中于1000bp左右。分别从枣花和枣叶SSH文库中随机挑选1000个阳性克隆进行DNA测序、组装拼接，结果显示枣花SSH文库中获得96条unigene，其中contigs43个，singletons53个，96条unigene预测得到73个ORF，经过同源比对分析获得有注释的序列20条，按功能分为7类；枣叶SSH文库中获得86条unigene，其中contigs45个，singletons41个，86条unigene预测得到70个ORF，经过同源比对分析获得有23条注释的序列，按功能分为6类。

Z. jujube shows some special characters of flowering and fruit bearing. In order to obtain genes involved in blossom development, two suppression subtractive cDNA libraries were constructed using developing blossoms of ＇Jinsi No.4＇ as tester and leaves as driver. The recombination rates of the SSH libraries from Z. jujube＇s flowers and leaves were 92.05% and 90.26%, with the length of inserted fragments ranged from 200 to 2 000 bp, and mainly focusing on 1 000 bp. A total of 1 000 positive clones were randomly selected from the SSH libraries of Z. jujube＇s flowers and leaves respectively for DNA sequencing and assembled. Consequently, 43 contigs, 53 singletons, 73 ORFs, 96 unigenes and 20 annotated sequences were obtained from SSH library of Z. jujube＇s flowers. Forty-five contigs, 41 singletons, 70 ORFs, 86 unigenes and 23 annotated sequences were obtained from SSH library of Z. jujube＇s leaves, and the annotated sequences could be divided into six groups.