The ascomycete fungus Cordyceps militaris infects lepidopteran insect pupae, forming characteristic fruiting bodies called “Dong Chung Ha Cho” in Korean. They have been used as medicines owing to their anti-allergic, anti-inflammatory, and immune-enhancing effects. This fungus can be grown on the geminated soybeans Rhynchosia nulubilis, which also contains several novel isoflavones. We performed a comparative transcriptome analysis to determine core gene sets or pathways contributing to biologically active products such as isoflavone. Initially, we sequenced 2-week-old fungal cultures on different soybean agar media, where different amounts of water agar were implemented to show different surface topology. We selected 830 upregulated and 188 downregulated genes by comparing linear models of the samples (two-fold change threshold). Gene ontology analysis identified that the “IMP biosynthesis” term was significantly found in the upregulated gene sets. The pathway is involved in the synthesis of cordycepin, the reference chemical for C. militaris. This finding in the transcriptome data is consistent with the previous observation: increased cordycepin concentrations in the C. militaris cultured on germinated soybean.

ABSTRACT
Introduction
Materials and Methods
    Fungal isolates and Fungal culture on thegerminated soybeans and its sampling
    Extraction of RNA and RNA-Sequencing
    Read filtering, mapping, and expression quantification
    Gene ontology
    Real-time quantitative reverse transcriptionPCR (qRT-PCR)
Results and Discussion
    Growth on different germinated soybeans agar
    Overall similarity between samples
    Differential gene expression
    Gene ontology and pathway analysis
REFERENCES

• Chang-Hyuk Yoo(Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University)
• Jaehyuk Choi(Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University) Corresponding author