[Construction of a reverse-subtracted cDNA library for differentially expressed genes in rat liver of prothrombotic state].

OBJECTIVE: To inquire into the mechanism of prothrombotic state (PTS) and the roles of liver therein by constructing a reverse-subtracted cDNA library for differentially expressed genes in rat liver of PTS. METHODS: The reverse-subtracted cDNA library for differentially expressed genes in rat liver of PTS was constructed by suppression subtractive hybridization. The rat model of PTS was induced by a high-carbohydrate diet. Poly A+ mRNAs were isolated from PTS and control rats, and cDNAs were synthesized from the mRNAs. After digestion by means of Ras I, cDNAs 400-600 bp in size were obtained. For suppression subtractive hybridization, cDNAs from PTS rat were used as Driver and the cDNAs from control rat as Tester. The Tester was divided into two parts and ligated to adaptor 1 and adaptor 2R respectively. After two times of subtractive hybridization and two times of nested PCR, the products of the last PCR amplification were inserted into T/A plasmid vectors to transform the Escherichia coli JM109 cells. The transformed cells were incubated at 37 degrees C overnight on a LB agar plate containing ampicillin (50 micrograms/ml), IPTG and X-gal. The colonies were counted. RESULTS: 78% of the colonies were white and the reverse-subtracted cDNA library for differentially expressed genes in rat liver of prothrombotic state was successfully constructed. CONCLUSION: Prothrombotic state caused by malfunction of homeostasis and fibrinolysis is an important risk factor of cardiovascular disease. Liver plays important roles in the development of PTS, for the majority of the factors in the coagulation as well as fibrinolytic cascades are generated by the liver and secreted into the bloodstream. The reverse-subtracted cDNA library for differentially expressed genes in rat liver of PTS, successfully constructed in the present study, provides an efficient way to further investigate the mechanism of PTS and the relevant liver functions.