The Construction Of Cdna Libraries And Analysis Of Differentially Expressed Genes At Maturation Stages Of Ricinus Communis Embryo

Ricinus (Ricinus communis L.) is one of the special oil crops in the world. They are widely distributed. The castor oil can be derived from R. communis. But the fatty acid metabolism mechanism aspect of R. communis had few research, and even about fatty acid pathways just from the single genes, few of them researched the fatty acid synthesis metabolism network from the R. communis seed growth. How to find the key factors from complex biochemistry system, expounds its biology function and transformation it according to people's needs were very important. It's very useful to improve its fatty acid composition. R. communis originates form china, and "youbi 5 hao" is a special in China. Suppression subtractive hybridization (SSH) is a matured and high efficient tool to find the differentially expressed genes. Using SSH to compare with the two variety growth steges of R. communis in gene expression differences can search the key factors arising oil content difference, build the foundation for the later period research. Research results is as follows:Forward cDNA libraries were constructed with the 15 DAF embryo as driver and the 35 DAF embryo of "youbi 5 hao" as tester by SSH. The subtraction efficiency of the subtracted libraries were above 210. The seven hundred clones were picked out randomly by PCR, and five hundred and ninety-six positive clones were obtained. The efficiency of the effective recombination was above eighty-five percent. The lengths of the inserted fragments were five hundred base pair on average. Five hundred and twenty-one ones were sequenced after dot hybridization. After the combination and the classification to the sequence information by biological information, total ninety-six genes containing thirty-one unigenes and sixty-five known genes, and these genes were relative to the synthesis of oil, degradation of sugar, degradation and transport of protein and so on.By analysing the expression of five differentially expressed genes in R. communis tissues, R. communis oleosin (OLE1), R. communis seed storage protein and Arabidopsis thaliana NLP1 and so on, it was shown that these genes were expressed richly in R. communis embryo. The expression of these genes at the different stages of R. communis oleosin was in the same way. It was shown that they were differentially expressed at the different stages.