西藏青稞品种藏青13高氮处理的SSH文库构建及分析

Construction and Analysis of the SSH Libraries of the Tibetan Hulless Barley Variety Zangqin 13 Treated with High Nitrogen

为了分析青稞高氮处理相关基因的表达,以藏青13为实验材料,通过抑制差减杂交构建了青稞高氮处理下的差减c DNA文库。在随机挑取的281个阳性克隆中,测序获得219条高质量的EST,含有212条非重复且与Genbank中的基因或蛋白具有较高的同源性的序列。对其进行Blast2Go功能注释可将差异表达的基因定位到细胞组件、分子功能和代谢过程3大类内。通过KEGG代谢途径分析,212个比对结果中的117个ESTs有详细的KO功能注释,定位到17个具体的代谢途径上,且主要定位在光合作用碳固定途径和氮素代谢途径。此外,分析还发现这些基因主要是编码参与结构和功能代谢合成途径中的一些酶,且参与信号转导、转录调节和光合作用等生理过程,说明这些基因很可能参与到青稞在高氮处理下的抗性反应中。

To analyze the genes responsive to high- nitrogen treatment in Tibetan hulless barley,suppression subtractive hybridization（ SSH） was utilized to construct the differential expression c DNA libraries using the hulless barley variety Zangqin 13. From the two constructed c DNA libraries,281 positive clones were randomly selected and subjected to sequencing; consequently,219 qualified ESTs containing 212 unigenes were obtained. The similarity analysis of expressed sequence tags（ ESTs） of these unigenes was performed with Blastx and Blastn against the non- redundance database in Gen Bank. The results showed that the 212 sequences were homologous with some genes or proteins in Gen Bank,which are responsible for biological process,cellular components,and molecular functions according to the analysis of Blast2 Go. In the analysis of KEGG,117 ESTs of the 212 sequences were mapped to 17 metabolic pathways. Specifically,these unigenes encode enzymes that are involved in the structure and function of some metabolic synthesis pathways; as well as in signal transduction,transcriptional regulation,and photosynthesis. This suggests that these genes may contribute to the tolerance of Tibetan hulless barley to high nitrogen treatment.