The Study On Distribution Of Uncoupling Protein And Phylogenesis Of Tree Shrew

The article began from the effects of cold exposure on gene expression of UCPs in BAT, liver, and skeletal muscle of tree shrew, then the distribution of UCP1, UCP2 and UCP3 in BAT, liver, SM, and Brain were identified to search for UCPs of tree shrews in different tissues. RT-PCR method was used in BAT of tree shrews and sequenced the PCR production for researching the phylogenesis of tree threws. The phylogenetic tree was built with MEGA3.0 software by matrix-likelihood method.The thesis is consists of three parts:1. The effects of cold exposure on gene expression of UCPs in BAT, liver, and skeletal muscle were studied.2. The distribution of UCP1, UCP2 and UCP3 were identified in BAT, liver, and skeletal muscle of tree shrews.3. The phylogenetic tree of UCPs was constructed for researching the phylogenesis of tree shrews.The results and conclusions:1. After 28d cold acclimating, the weight of body, the relative weights of BAT, liver and skeletal muscle, and the total RNA and proteins increased significantly comparedwith the control group(0day). This results suggested that UCPs could play a role in adaptive thermogenesis in tree shrews.2. The gene of UCP1 was identified in BAT exclusively, and the gene of UCP2 in BAT, liver and skeletal muscle, and the gene of UCP3 in BAT and skeletal muscle. The study of the distribution of UCPs in different tissues could contribute to studying the functions of UCPs.3. The partial cDNA sequence of UCP1 in tree shrews was sequenced. And compared with other animals and plants' UCPs sequences, the phylogenetic tree was constructed to analyse the phylogenesis of tree shrews. The results suggested that the relationship between tree shrews and primates are close. Meanwhile, the close relationship between UCP2 and UCP3 was shown.Conclusion:In a word, the total RNA and proteins of BAT, liver and skeletal muscle in tree shrews increased markedly after cold acclimated, which suggested that skeletal muscle can play a complementary role in adaptive thermogenesis in minitype mammals. Moreover, the mRNA of UCP2 and UCP3 were identified in skeletal muscle, which have implicated that skeletal muscle could be correlate to adjusting adaptive thermogenesis. Combined with the previous results that increasing of mitochondrial respiration in skeletal muscle after cold acclimated from our team, we concluded that skeletal muscle play a complementary role on adaptive thermogenesis.The phylogenetic tree of UCPs suggested that the phylogenetic relationship between tree shrews and primates are close, and sister group. And then, the clade of scandentia-primates joined with rodents. This results is accord with most reports. The phylogenetic relationship between UCP2 and UCP3 are most closest among UCPs.