Jul 2026· Pest Management Science· 0 citations· 41 references
Medicine
TL;DR
TF1-TF6 play essential roles in the positive regulation of insect-pathogenic lifecycle and serve as negative regulators of submerged blastospore production in vitro in B. bassiana.
Abstract
Background
A family of 54 fungal specific transcription factors (FsTFs) with the FsTF domain fungal_TF_MHR or fungal_trans_2 coexist with a large class of 202 C6 transcription factors (TFs) with Zn(II)2Cys6 binuclear cluster DNA-binding (C6) domain alone or both C6 and FsTF domains in Beauveria bassiana, a wide-spectrum mycoinsecticide. FsTFs and C6 TFs are often confused with each other and are generally underexplored, making it necessary to explore their regulatory roles in the fungal insect-pathogenic lifecycle. Here, six FsTFs (TF1-TF6) with different (representative) molecular sizes and unique size-different FsTF domain located in different sequence regions are functionally characterized.
Results
The deletion mutants of tf1-tf6 were much more compromised in virulence via normal cuticle infection (NCI) than cuticle-bypassing infection (intrahemocoel injection). The markedly attenuated virulence via NCI was ascribed to severely blocked secretion of cuticle-degrading enzymes required for hyphal invasion into host hemocoel through cuticular penetration. All the mutants also exhibited increased sensitivities to hyperosmotic, oxidative and cell wall perturbing stresses, impaired conidial quality, and sharp increases in submerged blastospore production in vitro despite negligible changes in aerial conidiation and radial growth on different carbon or nitrogen sources. The altered phenotypes were well restored by targeted gene complementation.
Six subclass III C6 transcription factors with unique Zn(II)2Cys6 binuclear cluster DNA-binding DNA-binding domain not locating at N-terminus are underexplored in Beauveria bassiana and a significance of host immune suppression for the insecticidal activity of B. bassiana is unveiled.
Jian-Ru Feng, Min Li, Shenghua Ying et al.· Journal of Invertebrate Path...· 0 citations
It is demonstrated that MrFTRP1 exerts a dual-regulatory functioning as a positive regulator of conidiation and pathogenesis but a negative regulator of environmental stress tolerance, which expands the understanding of the regulatory diversity within the C6 TF family and identifies him as a promising target for the genetic improvement of mycoinsecticides.
Chentian Jiang, Hao Wu, You-Gui Tong et al.· Journal of Invertebrate Path...· 0 citations
It is shown that the understudied bZIP transcription factor PnAda1 is an important downstream component of this PnPf2-regulatory network, and current understanding of the transcriptional network underlying virulence, metabolism and stress adaptation in an important fungal wheat pathogen is expanded.
S. Morikawa, Leon Lenzo, Keshara Colomba Thanthrige et al.· bioRxiv· 0 citations
Gene expression analysis revealed that certain genes, uniquely edited during the mating stage of MvSup, tend to be upregulated in the haploid stage but downregulated during mating, and vice versa, while the a2 haploid strain of MI had fewer editing sites compared to other haploid strains.
Shikhi Baruri, Nasara Shamsudeen, Alycia C. R. Lackey et al.· Journal of Fungi· 0 citations
Nuclear Factor Y, subunit A (NFYA) constitutes a family of transcription factors that play critical roles in plant growth, development and abiotic stress responses. Taxodium hybrid ‘Zhongshanshan’ (T. mucronatum × T. distichum) is a fast-growing tree species with high industrial value and remarkable flooding tolerance. However, the systematic characteristics and abiotic stress response patterns of the ThNFYA gene family remain unclear. In this study, a total of 11 ThNFYA genes were identified. The encoded proteins ranged from 67 to 372 amino acids in length, with predicted molecular weights between 16.84 and 40.12 kDa. Phylogenetic analysis classified plant NFYAs into four clades, with all ThNFYAs falling into clades I and IV. Expression profiling revealed tissue-specific patterns, with six members showing the highest transcript levels in the cambium. Multiple cis-acting elements associated with stress and hormone responses were detected in the promoter regions of ThNFYAs. Most ThNFYAs were differentially regulated under salt, drought, and flooding stresses. Notably, most clade IV members (ThNFYA3, ThNFYA4, and ThNFYA6-ThNFYA8) were downregulated in the wood under partial submergence. This indicates their potential role in modifying wood properties in response to flooding. Co-expression network analysis identified ThNFYA1 and ThNFYA8 as central hub genes in leaves under partial submergence. Overall, these results suggest that the ThNFYA family may serve as candidate regulators of development and stress adaptation in T. hybrid ‘Zhongshanshan’. This study provides valuable insights for further functional verification of ThNFYAs and lays a foundation for marker-assisted breeding of stress-tolerant varieties.
Verticillium dahliae is a soil-borne vascular pathogen with a broad host range and the ability to survive in soil for extended periods through the formation of stress-resistant microsclerotia. It poses a major challenge to disease management and frequently causes severe Verticillium wilt in smoke tree (Cotinus coggygria) in China. Zn(II)2Cys6 transcription factors (TFs) represent a major class of fungal regulators and are involved in various biological processes, including primary and secondary metabolism, stress adaptation, and pathogenesis. In this study, we found that the deletion of VdRgt1, which belongs to Zn(II)2Cys6 TF, led to abnormal hyphal morphology, reduced vegetative growth, markedly decreased conidial production, and altered timing of microsclerotia development and melanin accumulation. Additionally, the ΔVdRgt1 mutant exhibited significantly reduced virulence and impaired colonization of C. coggygria. Transcriptome analysis indicated that VdRgt1 is involved in the regulation of carbohydrate and energy metabolism. Consistently, the ΔVdRgt1 mutant exhibited reduced ATP levels, and RT-qPCR supported a role for VdRgt1 in glucose-responsive gene regulation. Collectively, these results indicate that VdRgt1 is an important regulator in V. dahliae, coordinating hyphal development, the timing of microsclerotia development and melanin accumulation, carbon and energy metabolism, stress adaptation, and virulence.
