Experimental Center of Clinical Research, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, China.
Jiangsu Key Construction Laboratory of Food Resource Development and Quality Safe, Xuzhou University of Technology, Xuzhou, China.
Pest Manag Sci. 2019 May;75(5):1443-1452. doi: 10.1002/ps.5266. Epub 2018 Dec 24.
Insect pests have evolved various defense mechanisms to combat fungal infection, and fungi have developed multiple strategies to overcome the immune defense responses of insects. However, transcriptomic analysis of fungal strategies for infecting different pests has not been reported.
Transcriptomic profiling of Beauveria bassiana was performed at 12, 24 and 48 h after infecting Galleria mellonella and Plutella xylostella, and 540, 847 and 932 differentially expressed genes were detected, respectively. Functional categorization showed that most of these genes are involved in the ribosome, nitrogen metabolism and oxidative phosphorylation pathways. Thirty-one differentially expressed virulence genes (including genes involved in adhesion, degradation, host colonization and killing, and secondary metabolism) were found, suggesting that different molecular mechanisms were used by the fungus during the infection of different pests, which was further confirmed by disrupting creA and fkh2. Virulence assay results showed that ΔcreA and Δfkh2 strains of B. bassiana had distinct fold changes in their 50% lethal time (LT ) values (compared with the control stains) during infection of G. mellonella (ΔcreA: 1.38-fold > Δfkh2: 1.18-fold) and P. xylostella (ΔcreA: 1.44-fold < Δfkh2: 2.25-fold). creA was expressed at higher levels during the infection of G. mellonella compared with P. xylostella, whereas fkh2 showed the opposite expression pattern, demonstrating that creA and Fkh2 have different roles in B. bassiana during the infection of G. mellonella and P. xylostella.
These findings demonstrate that B. bassiana regulates different genes to infect different insects, advancing knowledge of the molecular mechanisms of Beauveria-pest interactions. © 2018 Society of Chemical Industry.
昆虫已经进化出各种防御机制来对抗真菌感染，而真菌也发展出多种策略来克服昆虫的免疫防御反应。然而，真菌侵染不同害虫的策略的转录组分析尚未见报道。
对球孢白僵菌在侵染大蜡螟和小菜蛾后 12、24 和 48 小时的转录组进行了分析，分别检测到 540、847 和 932 个差异表达基因。功能分类表明，这些基因大多参与核糖体、氮代谢和氧化磷酸化途径。发现了 31 个差异表达的毒力基因（包括参与黏附、降解、宿主定殖和杀伤以及次级代谢的基因），这表明真菌在侵染不同害虫时使用了不同的分子机制，这进一步通过敲除 creA 和 fkh2 得到了证实。毒力测定结果表明，与对照菌株相比，B. bassiana 的ΔcreA 和Δfkh2 菌株在感染大蜡螟（ΔcreA：1.38 倍>Δfkh2：1.18 倍）和小菜蛾（ΔcreA：1.44 倍<Δfkh2：2.25 倍）时其半数致死时间（LT）值的变化倍数有明显差异。与感染小菜蛾相比，creA 在感染大蜡螟时的表达水平更高，而 fkh2 的表达模式则相反，这表明 creA 和 Fkh2 在 B. bassiana 感染大蜡螟和小菜蛾时具有不同的作用。
这些发现表明，B. bassiana 调控不同的基因来感染不同的昆虫，从而提高了对白僵菌-害虫相互作用的分子机制的认识。© 2018 化学工业协会。
