Study On The Spatiotemporal Expression Of GPx5 On Camel Epididymis

Mammalian spermatozoa acquire the ability of fertilization during the transport,protection and storage of epididymis,which is the main place for sperm maturation and storage.Sperm are just as susceptible to oxidative damage as any other type of cell.Sperm is very sensitive to lipid peroxidation and DNA damage,which affect the viability and fertilization ability.Epididymis provides an environment free of external pressure for sperm and promotes maturation.Epididymis contains a series of antioxidants,including glutathione peroxidase 5(GPx5),which protects sperm from oxidative stress,maintains normal levels of free radicals in the male reproductive tract,promotes sperm maturation,and plays an important role in improving male fertility.There is no domestic research on GPx5 gene in camel epididymis.Therefore,this study used camels as the research object and tested the expression of GPx5 in different parts of camel epididymis at different ages(three,five,and six years old).The research results are as follows:1.Fluorescence quantitative PCR technology was used to detect the mRNA expression of GPx5 gene in different parts of camel epididymis at different ages.Fluorescence quantitative PCR results showed that there were differences in epididymis expression levels in camels aged 3,5 and 6.The caput of epididymis in camels aged three,five and six were the main expression areas of GPx5 mRNA,which was significantly higher than the corpus and cauda(P<0.01).There was no significant difference among the three(P>0.05).Only trace expression GPx5 gene was detected in the corpus of epididymis and cauda of epididymis in camels aged 3,5 and 6.2.Western blot was used to detect GPx5 protein expression in different parts of epididymis of camels at different ages.Western blotting results showed that:GPx5 protein was expressed in different parts of epididymis of camels at different ages(3,5 and 6 years old).The expression of epididymis in camels at different ages was significantly different.The expression level of GPx5 protein in the epididymal caput of camels at 5 years old was significantly higher than that of camels at 3 years old and 6 years old(P<0.01),while the expression level of GPx5 protein in the epididymal caput of camels at 3 years old was not significantly different from that of camels at 6 years old(P>0.05).(P<0.01),while the expression level of GPx5 protein of camels at three was not significantly different from that of camels at six(P>0.05).The comparison of the same parts in all age groups showed that the relative expression levels in all parts of epididymis of camels at the age of five were significantly higher than those in other two age groups.3.Immunohistochemistry was used to detect the protein distribution of GPx5 protein in different parts of epididymis of camels at different ages.The immunohistochemical results showed that GPx5 protein was lagerly expressed in epithelium and stereocilium of the caput of epididymis in camels of 3 years old,5 years old and 6 years old,and the epididymis corpus and cauda were mainly expressed in the static cilium of epithelial cells.In addition,there were significant GPx5 positive signals in the lumen in epididymis of camels at all ages.The results showed that GPx5 protein was mainly expressed in epithelium and stereocilium of the caput of camel epididymis,and a small amount in epididymis corpus and cauda.