Screeing And Identification Of Clock Genes In Mouse Mammary Gland

Biological rhythm is the basic phenomenon of life. Biological clocks play an important role to regulate organism adapt to the environment in a variety of genes, different cells and different organizations. When we reseach the life phenomen must concern circadian rhythem since the role of the circadian is so extensive and important. Reseach the network of clock genes and the regulation mechanism of circadian clock to mammary gland is very important. Screened differently expressed genes among diffenent stages and different time of mammary gland in this study. Analysis genes function that differently expressed. In this experiment, mouse genomic gene chip430of Affymetrix was used to screen differentially expressed genes in different development periods of mouse mammary gland. And gene expression profile was obtained by comparison of gene expression between lactation and innovation. At the same time, the results were verified by fluorescence quantitative RT-PCR. In this experiment,965differentially expressed genes were screened out by comparison of day and night in lactation, and629genes were high expression and336genes were low expression at day time.5317differentially expressed genes were screened out by comparison of lactation and involution, and2137genes were high expression and3180genes were low expression at lactation. The results showed that differentially expressed genes in lactation stage, were mainly focused on the synthesis and secretion of milk. Day and night differential expression genes function, were mainly concentrated in the biological rhythms. Screened differentially expressed genes in the Pathway analysis, and relatively active signaling Pathway. According to the microarray array results, we use quantitative PCR method to study Per1, Per2, Bmall, Cry1and Cry2genes which differently expressed in different development stage and different time point. The results showed that the Per2and Bmall have larger impact on mammary gland development.Per2exhibited a increased expression in mammary gland during adolescence and middle pregnancy (P<0.05). Bmal exhibited a increased expression in mammary gland during lactation and involution (P<0.05), but exhibited a low expression in mammary gland during adole scence and middle pregnancy (P<0.05). Per1, Cry1and Cry2were basically no effect to mammary gland development (P>0.05). Rhythm analysis of Clock gene in SCN and mammary gland show that at LD conditions the phase of Clock in mammary gland have a reverse relationship to SCN, and at DD conditions the phase of Clock in mammary gland have the same relationship to SCN. Analyzing the Clock and Per1genes function with RNA interference technology. Casein and lactose detected by HPLC, triglycerides detected by UV absorptionassay. The results show that the Clockgene inhibit milk protein, lactose and triglycerides synthesis (P<0.05). Perl gene inhibit milk protein, lactose and triglycerides synthesis too.