Expressions Of DNA Methylation And Histone Acetylation Related Genes In Response To Bacterial Infection In Silkworm, Bombyx Mori

The silkworm is a very important economic insect for the silk production. Nevertheless, it often causes huge economic loss to sericulturist since silkworms are easily infected by pathogenic microbes in breeding. Hence, it’s necessary to study the molecular basis that how the silkworm defenses pathogens thoroughly, so as to provide the theoretical basis for the prevention and control of silkworm diseases. Therefore, we attempt to investigate whether epigenetic modification, DNA methylation and histone acetylation/deacetylation, are involved in the regulation of the immune responses in the silkworm, Bombyx mori.We screened out 5 related genes(BmDNMT1 、 BmDNMT2 、 BmHDACI-1 、BmHDACI-2、BmHAT1) from silkworm genome according to the sequenses of HsDNMTs, HsHDACs, HsHATs for the following study.We found the sequences of DNA Methyltransferase 1(DNMT1), Histone deacetylase(HDAC) I-1, I-2 and Histone acetylase 1(HAT1) of other species according to BmDNMT1, BmHDAC and BmHAT. We also performed phylogenetic analysis of DNMT1, HDACI-1, I-2 and HAT1 from Bombyx mori and other species. The phylogenetic analysis indicated that BmDNMT1 is particular special, independent of other insect taxa. BmHDACs and BmHAT1 are evolutionary conservation.Then, we also detected the mRNA levels of BmDNMT1, BmHDACs and BmHAT1 by Q-PCR. As expected, we found that their expression levels in the fat body changed significantly after infected by Pseudomonas aeruginosa and staphylococcus aureus. However, we did not detect obvious effect of DNMT, HDAC or HAT inhibitors on the survival of larval silkworm after bacterial challenge.Taken together, our results suggest that DNA methylation and histone acetylation/deacetylation might be involved in the regulation of silkworm immune responses.