The Effect Of Human-derived DNMT3A Overexpression On DNA Methylayion Pattern Of Rat Sperm

Objective: In recent years,DNA methylation has been the major focus of studies on paternal epigenetic inheritance in mammals.However,most previous studies about inheritable DNA methylation changes are passively induced by environmental factors.It is still unclear whether the active changes mediated by variations in DNA methyltransferase activity are heritable.Here,we established human-derived DNMT3 A transgenic rats to study the effect of h DNMT3 A overexpression on the DNA methylation pattern of rat sperm and to investigate whether this actively altered DNA methylation status is inheritable.Methods and Results: 1.h DNMT3 A was overexpressed in the testis of transgenic rats by RT-q PCR Analysis;2.among 5438 reliable loci identified with 64 primer-pair combinations by methylation-sensitive amplification polymorphism method,28.01% showed an altered DNA methylation status in the offspring of transgenic rats compared with wild-type rats.Of which,42.48% occurred in both positive and negative offspring of transgenic rats;3.75.07% inheritable loci tended to be hyper-methylated,and the remaining loci were demethylated;4.Sequencing analysis showed that 56.25% of differentially methylated loci(DMLs)were found in intergenic regions,while 31.25% occurred in introns and 12.50% occurred in exons;5.Gene Ontology analysis revealed that genes related to DMLs were involved in a wide range of functions.Conclusions: intergenerational inheritance of active DNA methylation changes can be found in the absence of h DNM3 A transmission,which provided powerful evidence for the transmission of active endogenous-factor-induced epigenetic variations.