FluG and FluG-like FlrA Coregulate Manifold Gene Sets Vital for Fungal Insect-Pathogenic Lifestyle but Not Involved in Asexual Development.

The central developmental pathway (CDP) activator gene is activated by the upstream genes and - in Aspergillus nidulans. Increasing evidences of fungal genome divergence make it necessary to clarify whether such genetic principles fit Pezizomycotina. Previously, disruption resulted in limited conidiation defect and little effect on the expression of and - in Beauveria bassiana possessing the other FluG-like regulator FlrA.

Characterization of BbKlf1 as a novel transcription factor vital for asexual and infection cycles of Beauveria bassiana.

The large family of C2H2-type zinc finger transcription factors (TFs) comprise the Kruppel-like factors (KLFs) that evolved relatively late in eukaryotes but remain unexplored in filamentous fungi. Here, we report that an orthologue (BbKlf1) of yeast Klf1 mediating cell wall integrity (CWI) is a wide-spectrum TF evidently localized in nucleus and cytoplasm in Beauveria bassiana. BbKlf1 features conserved domains and multiple DNA-binding motifs predicted to bind multiple promoter DNA fragments of target genes across asexual developmental and stress-responsive pathways.

Differential Roles of Five Fluffy Genes (-) in the Lifecycle In Vitro and In Vivo of the Insect-Pathogenic Fungus .

The fluffy genes - are well-known players in the upstream developmental activation pathway that activates the key gene of central developmental pathway (CDP) to initiate conidiation in . Here, we report insignificant roles of their orthologs in radial growth of under normal culture conditions and different stresses although and were involved in respective responses to heat shock and HO. Aerial conidiation level was lowered in the deletion mutants of and (~15%) less than of and (~30%), in which the key CDP genes and were repressed consistently during normal incubation.

Distinctive role of fluG in the adaptation of Beauveria bassiana to insect-pathogenic lifecycle and environmental stresses.

The upstream developmental activation (UDA) pathway comprises three fluG-cored cascades (fluG-flbA, fluG-flbE/B/D and fluG-flbC) that activate the key gene brlA of central developmental pathway (CDP) to initiate conidiation in aspergilli. However, the core role of fluG remains poorly understood in other fungi. Here, we report distinctive role of fluG in the insect-pathogenic lifecycle of Beauveria bassiana.

Two white collar proteins protect fungal cells from solar UV damage by their interactions with two photolyases in Metarhizium robertsii.

The photolyases PHR1 and PHR2 enable photorepair of fungal DNA lesions in the forms of UV-induced cyclobutane pyrimidine dimer (CPD) and (6-4)-pyrimidine-pyrimidone (6-4PP) photoproducts, but their regulation remains mechanistically elusive. Here, we report that the white collar proteins WC1 and WC2 mutually interacting to form a light-responsive transcription factor regulate photolyase expression required for fungal UV resistance in the insect-pathogenic fungus Metharhizum robertsii. Conidial UVB resistance decreased by 54% in Δwc1 and 67% in Δwc2.

Daylight length-dependent translocation of VIVID photoreceptor in cells and its essential role in conidiation and virulence of Beauveria bassiana.

The fungal insect pathogen Beauveria bassiana has the blue-light photoreceptor VIVID (VVD) but lacks a pigmentation pattern to trace its light responses. Here, we show that the fungal vvd is transcriptionally expressed, and linked to other blue/red photoreceptor genes, in a daylight length-dependent manner. GFP-tagged VVD fusion protein was localized to periphery, cytoplasm and vacuoles of hyphal cells in light/dark (L:D) cycles of 24:0 and 16:8 and aggregated in cytoplasm with shortening daylight until transfer into nuclei in full darkness.