College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, China; Hubei Province Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hubei Key Laboratory of Quality Control of Characteristic Fruits and Vegetables, College of Life Science and Technology, Hubei Engineering University, Xiaogan, China.
College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, China; School of Life Sciences, Southwest University, Chongqing, China.
J Invertebr Pathol. 2024 Mar;203:108059. doi: 10.1016/j.jip.2024.108059. Epub 2024 Jan 9.
Beauveria bassiana, a well-known filamentous biocontrol fungus, is the main pathogen of numerous field and forest pests. To explore the potential factors involved in the fungal pathogenicity, Bbhox2, an important and conserved functional transcription factor containing homeodomain was carried out by functional analysis. Homologous recombination was used to disrupt the Bbhox2 gene in B.bassiana. The conidia yield of the deletant fungal strain was significantly reduced. The conidial germination was faster, and stress tolerance to Congo red and high osmotic agents were decreased compared with that in the wildtype. Additionally, ΔBbhox2 showed a dramatic reduction in virulence no matter in topical inoculations or in intra-hemolymph injections against Galleria mellonella larvae, which is likely due to the failure of appressorium formation and the defect in producing hyphal body. These results indicate that the Bbhox2 gene markedly contributes to conidiation and pathogenicity in B. bassiana.
球孢白僵菌是一种著名的丝状生防真菌，是许多田间和森林害虫的主要病原体。为了探索真菌致病性涉及的潜在因素，对含有同源域的重要且保守的功能转录因子 Bbhox2 进行了功能分析。通过同源重组敲除了 B.bassiana 中的 Bbhox2 基因。缺失菌株的分生孢子产量显著降低。与野生型相比，分生孢子的萌发速度更快，对刚果红和高渗剂的应激耐受性降低。此外，ΔBbhox2 在针对家蚕幼虫的体表接种或血腔注射中的毒力均显著降低，这可能是由于附着胞形成失败和产生菌丝体的缺陷。这些结果表明，Bbhox2 基因显著促进了球孢白僵菌的分生孢子形成和致病性。
