Selecting Heat Stress-Related Genes Of Dairy Cows With Gene-Chip

30 Holstein cows and 25 Israeli Holstein cattle (♂)×Chinese Holstein (♀) F1 blood sample was collected from Yi Kang Dairy Cattle Farm in Jinhua. Due to different ability to resist high temperatures in the two groups. And trait is determined by gene. It is suggested that there are differences in the gene expression which related to heat stress. Fresh blood were exposed at 42℃temperature for 1 hour or 4 hour also casued differences in the gene expression which related to heat stress. We selected Affymetrix genechip for studying differences in the gene expression which related to heat stress. The result of genechip showed that CCL3 was upregulated after exposed to 42℃high temperature for 1 hour or 4 hour. There is no full-lenth sequence in genbank, so we cloned full-lenth sequence of CCL3 of dairy cows. Moreover, we did preliminary bioinformatics analysis of the sequence.The results were as follows:â‘ There were 257(139 up-regulated and 118 down-regulated) 2-times differential display genes in the comparison groups. There gene function are involved in apoptosis(22/4,22 up-regulated,4 down-regulated, the same below), immune response(14/19), redox reaction(3/8), cell proliferation and division(5/7), metabolism (14/19), signal transduction(14/8), regulation of transcription(16/5), others (26/62). There biological functions are closely linked to dairy cows heat stress reaction. And they reflected molecular basis of heat stress reaction. Heat shock proteins and chemo-kine family are particular closely associated with heat stress of dairy.â‘¡We successfully cloned a full-length cDNA sequence of CCL3 in dairy cow. CCL3 NM₁74511 sequence logged in the Genbank was 361 bp long. We extended this sequence 453 bp in 3'end and 15 bp in 5'end. The CCL3 protein is homology with Bubalus bubalis by 95%, Sus scrofa is 88%, Felis catus is 81%, Equus caballus is 79%, Oryctolagus cuniculus and Rattus norvegicus are 75%, Canis lupus familiaris is 74%, Mesocricetus auratus is 73%, Mus musculus is 72%, Homo sapiens, Pan troglodytes and Sigmodon hispidus are 70%, Macaca mulatta is 66% only.All in all, differentially expressed genes obtained in this study are important for further studying the molecular basis of heat resistance of dairy cows. Also it provided a series of genes helpful for dairy cows molecular breeding.