Nakamura Yosuke, Nguyen Ngoc-Hung, Yoshinari Tomoya, Hachisu Masakazu, Nguyen Phuong-Thao, Shimizu Kiminori
a Department of Biological Science and Technology, Tokyo University of Science.
b Department of Computational Biology and Medical Science, Graduate School of Frontier Sciences, The University of Tokyo.
Mycoscience. 2024 Mar 31;65(2):96-104. doi: 10.47371/mycosci.2024.02.005. eCollection 2024.
(≡ ) is an entomopathogenic fungus that hosts lepidopteran insect larvae. Oosporein, produced by , is a red secondary metabolite that is also produced by other entomopathogens and is known to contribute to entomopathogenic activity. In this study, a homologous region of the oosporein biosynthesis gene cluster ( cluster) was found from the genome sequence of strain NBRC 103832. Within the cluster, a putative transcription factor gene was deleted by homologous recombination. The deletion strain () did not produce oosporein. Real-time qPCR analysis showed that the expression of all genes was either lost or greatly reduced compared to the wild type strain (WT). Infection assay using silkworms showed that the virulence of the strain was not different from that of the WT strain. We compared the expression levels of antimicrobial peptide genes in silkworm infected with these strains, and found that the increased expression of the gene in WT was not observed in the strain, suggesting that the immune response of the silkworm was altered.
(≡ )是一种寄生于鳞翅目昆虫幼虫的昆虫病原真菌。由 产生的卵孢素是一种红色次生代谢产物，其他昆虫病原体也能产生，已知其有助于昆虫致病活性。在本研究中，从 菌株NBRC 103832的基因组序列中发现了卵孢素生物合成基因簇（ 簇）的一个同源区域。在该簇内，通过同源重组删除了一个假定的转录因子基因 。缺失菌株（ ）不产生卵孢素。实时定量PCR分析表明，与野生型菌株（WT）相比，所有基因的表达均丧失或大幅降低。使用家蚕进行的感染试验表明， 菌株的毒力与WT菌株无异。我们比较了感染这些菌株的家蚕中抗菌肽基因的表达水平，发现 菌株中未观察到WT中 基因表达的增加，这表明家蚕的免疫反应发生了改变。
