The Role Of Autophagy Inhibiting Exogenous Gene Expression And Mumps Virus Replication In Spermatogenic Cells

Background and objectives:Spermatogenic cells hardly express exogenous genes and efficiently restrict mumps virus(MuV)replication,underlying mechanism remain to be clarified.This thesis explored roles of autophagy in inhibiting exogenous gene expression and MuV replication in mouse spermatogenic cells.Materials and methods:Male germ cells at different developmental stages and testicular somatic cells were isolated from male mice.Cells were infected by the adenovirus with fluorescent tags and MuV.Gene expression at mRNA levels was examined using real-time quantitative RT-PCR.Proteins were quantitatively analyzed by Western-Blot.Protein distribution was determined using immunohistochemistry and immunofluorescence staining.Results:Fluorescent protein of adenovirus can be detected in Sertoli cells,Leydig cells,Spermatogonia,but not in round spermatids.Beclin-1 and microtubule-associated protein light chain 3(LC3)are two critical autophagy-related proteins.Male germ cells abundantly expressed Beclin-1 and LC3.In the presence of rapamycin(Rap),an autophagy inducer,Sertoli and Leydig cells do not express fluorescent protein.By contrast 3-Methyladenine(3MA),an autophagy inhibitor,favor fluorescent protein expression in spermatogenic cells.Moreover MuV do not replicate in spermatogenic cells.However MuV can replicate in the presence of 3MA.Conclusions:Mouse spermatogenic cells possess high autophagy activity,which inhibits exogenous gene expression and restricts MuV replication.The results provide novel insights into mechanisms underlying male germ cell defence against MuV and inhibitition of exogenous gene expression in spermatogenic cells.