Project description:Genome-wide analysis of DNA methylation for asexual and sexual stages of Cordyceps militaris DNA methylation is a basic epigenetic mechanism found in eukaryotes, but its patterns and roles vary significantly among diverse taxa. In fungi, DNA methylation has various effects on diverse biological processes; however, its function underlying the sexual development of fungi remains unclear. Cordyceps militaris, readily performing sexual reproduction, provides a remarkably rich model for understanding epigenetic processes in sexual development. The methylome was surveyed to assess DNA methylation patterns of the nascent fruiting body in C. militaris at single-base resolution by genomic bisulfite sequencing (BS-Seq). The results showed that around 0.4 % of cytosines are methylated, and that there is no difference compared with the DNA methylation level (0.39 %) during asexual development. However, 225 differentially methylated regions (DMRs) were identified between the stages. Moreover, RNA-Seq analysis indicated that the DMRs have no direct relation with the genes for fungal sexual development in C. militaris. DNA methylation regions from the BS-Seq show a striking correspondence to regions predicted to be repetitive and repeat-induced point mutation (RIP) mutated, suggesting that DNA methylation functions as a genome defense mechanism in sexual development. These results provide a comprehensive characterization of DNA methylation in the sexual development of C. militaris, which will contribute to future investigations of epigenetics in fungi. Bisulphite converted genomic DNA from the mycelium and fruitingbody of Cordyceps militaris
Project description:Cordyceps militaris and Cordyceps sinensis belong to belong to the same genus, but the different species, with immunity improvement, antibacterial, and antihypertensive effect, and the studies on the functions of Cordyceps militaris mainly focus on those of its polysaccharides and polypeptides. The latest studies have found that some of the polypeptides with immunomodulatory effect can widely regulate immune functions at multiple levels, improve immunity, and enhance immune functions to ensure the healthy body, showing an important significance. Cordyceps militaris polypeptide prepared with the enzymolysis method was taken as the research object in this study. The differentially expressed genes and the related cell signal transduction pathway were screened by mRNA expression microarray. STEM 1.3.6 software was used for the clustering of the gene functions, and David and KEGG database were applied for the analysis of the related functions. 1748 differentially expressed genes were selected finally and three of them were validated by qPCR. The results showed that gene Hist1h2bp, Ctsg, and Elane were involved in the regulation of Cordyceps militaris on the immune activity of mice. Gene Hist1h2bp, Ctsg and Elan may be the potential targets of Cordyceps militaris polypeptide, which may provide an important theory basis for the further research and development of Cordyceps militaris polypeptide.