The Heterotrimeric Transcription Factor CCAAT-Binding Complex and Ca ²⁺ -CrzA Signaling Reversely Regulate the Transition between Fungal Hyphal Growth and Asexual Reproduction

Abstract

A precisely timed switch between vegetative hyphal growth and asexual development is a crucial process for the filamentous fungal long-term survival, dissemination, biomass production, and virulence. However, under the submerged culture condition, filamentous fungi would undergo constant vegetative growth whereas asexual conidiation rarely occurs.

Role of the Heme Activator Protein Complex in the Sexual Development of Cryptococcus neoformans

“…In A. fumigatus , the HAP complex is composed of HapB, HapC, HapE, and HapX ( 11 , 47 , 48 , 55 ). Similar to our findings in C. neoformans , deletion of the HAP complex leads to the repression of conidiation in liquid submerged cultures, causing asexual conidiation ( 56 ). However, this phenomenon was not observed when the experiment was performed on solid medium—on solid medium, the HAP complex mutants displayed fewer conidia than the wild type.…”

“…In A. fumigatus , hapB deletion leads to upregulation of key conidiation regulatory genes, including brlA , a key regulator of conidiation. It was also reported that the A. fumigatus HAP complex binds to the CCAAT motif in the promoter region of brlA to repress its expression ( 56 ). Therefore, although the general ability of the HAP complex to bind to other CCAAT motifs of signaling components in the pheromone-responsive MAPK pathway during the developmental cycle remains to be elucidated, this phenomenon may be prevalent in other fungal species.…”

The sat1 Gene Is Required for the Growth and Virulence of the Human Pathogenic Fungus Aspergillus fumigatus

“…3 ). Spore development-related genes, including flbA , flbC , flbD , nosA , and nsdD ( 16 ), were upregulated in the RNA-seq data (Table S1 in the supplemental material), which was also validated by reverse transcription-quantitative PCR (qRT-PCR) ( Fig. 5C ).…”

Adaptive responses of erythritol-producing Yarrowia lipolytica to thermal stress after evolution

“…The Gcn2p kinase is involved in the nutritional stress response through the phosphorylation of eukaryotic initiation factor-2 (eIF2) and the general amino acid control pathway (Zaborske et al 2009 ). The CCAAT-binding transcription factor has been previously revealed to have roles in regulating sterol metabolism and the transition between fungal hyphal growth and asexual reproduction in Aspergillus fumigatus (Ren et al 2021 ). Moreover, it is clear that Pkc1 plays roles in many cellular processes, including the maintenance of cell wall integrity by regulating a mitogen-activated protein (MAP) kinase cascade (Dickson et al 2006 ; Canonero et al 2022 ).…”