Comparative Studies On Effects Of Hypoxia On Expressions Of Epo/Epor Gene In Brain Between Mandarin And Brandt's Voles

Oxygen often plays an important role in maintaining life activities such as survival and metabolism of organisms.When exposed to hypoxic conditions,organisms produce a series of reactions,such as metabolic disorders,system and tissue damage.Animals living in high-altitude or underground tunnels in an anoxic environment have undergone a series of changes in their morphology,physiology,and behavior to adapt to the hypoxic environment,enabling the body's systems to adapt to the hypoxic environment.The main role of Erythropoietin?Epo?and its receptor?Erythropoietin receptor Epor?is to promote the proliferation and differentiation of erythroid progenitor cells,the maturation of red blood cells,and neuroprotection and neurotrophic effects.As a typical underground mouse,the brown voles?Lasiopodomys mandarinus?live in the anoxic environment of underground tunnels for a long time.Although the related species L.brandtii is a ground mouse,both of them belong to Lasiopodomys.At present,there are few studies on the neuroprotective effects of Epo/Epor gene in different brain regions of them.Therefore,this study used a comparative biological method and took the brown voles as a target,Brandt's voles as a control,simulated different hypoxic environments in the laboratory hypobaric chamber,then,used in situ hybridization to determine the different brain regions of the two voles.The difference in Epo/Epor gene expression was to reveal the neuroprotective effect of Epo/Epor gene on hypoxic stress in mandarin voles,and provide a theoretical basis for hypoxic adaptation in underground mice.The main findings are as follows:1)Cloning of Epo/Epor gene of Brandt's vole and mandarin vole The Epo/Epor gene of Brandt's vole and mandarin vole was the same length,with Epo gene of 590 bp and Epor gene of 1583 bp.2)Adaptive evolution of Epo/Epor gene in Brandt's vole and mandarin vole The Epo/Epor gene system phylogenetic tree is consistent with the Cyt b phylogenetic tree topology,and there is no convergent evolution in the underground mouse.The brown voles and Brandt's voles coexist in the phylogenetic tree.The Epo/Epor gene was purified in evolution,and the Epor gene of the blind squirrel had an adaptive evolution site,and the 462-S and 467-G mutations located at the proximal end of the cytoplasmic region?P=0.03?;brown voles No positive selection sites were detected on the Epo/Epor gene of the voles.3)Effects of hypoxia on Epo/Epor gene expression in brain tissues of Brandt's vole and mandarin vole.Under different hypoxic exposures,Epo/Epor genes in the hippocampus of Brandt's voles and brown voles increased with increasing O₂concentration.(L.b:P _Epo=0.001,P _Epor<0.01;Lm:P _Epo=0.001;P _Epor<0.01);at different time periods of hypoxia?10%?exposure:Epo gene in the hippocampus of Brandt's vole at 24 h The expression level was the highest,and the expression decreased at 48h?P=0.031?.However,the expression of Epor gene increased with time?P<0.01?.The expression of Epo/Epor gene in the hippocampus of brown voles Time changes were increased(P _Epo<0.001;P _Epor<0.001).Under different hypoxic exposures,the expression of Epo/Epor gene in the cerebral cortex of the mandarin voles and Brandt's vole increased with the decrease of O₂ concentration(L b:P _Epo=0.025;P _Epor=0.004;L m:P _Epo=0.034;P _Epor=0.001);the expression of Epo gene in cerebral cortex of Brandt's vole increased with time at different time points of hypoxia?10%?exposure?P=0.012?;while Epor gene was at24h.The expression level was the highest,and the expression level decreased at 48h?P<0.001?.The expression of Epo/Epor gene in the cerebral cortex of the mandarin voles increased with time(P _Epo<0.001;P _Epor<0.001).Under different hypoxic exposures,the expression of Epo/Epor gene in the amygdala of Brandt's voles increased with the decrease of O₂ concentration(P _Epo=0.001;P _Epor=0.001);while the expression of Epo/Epor in the amygdala of the brown voles The amount was highest at 10%O₂ concentration,and the expression of Epo/Epor decreased at 5%O₂ concentration(P _Epo=0.082;P _Epor=0.087);under low oxygen?10%?exposure at different time stages,cloth The expression of Epo gene in the amygdala of the voles was the highest at 24h,but decreased at 48h?P<0.001?.The expression of Epor gene increased with time?P<0.001?.The Epo/Epor gene of the amygdala of the brown voles The expression level was the highest at 24h and decreased at 48h(P _Epo=0.002;P _Epor<0.001).Main conclusionsThe Epo/Epor gene of the brown voles and Brandt's vole did not show positive selection evolution.The brown voles have strong adaptation to hypoxia,and the Epo/Epor gene has a good neuroprotective effect.The neuroprotective mechanisms of different brain regions are different.The neuroprotective mechanism of the hippocampus and cerebral cortex is stronger,while the neuroprotection of the amygdala The mechanism is weak.