The C 2 H 2 transcription factor SltA is required for germination and hyphal development in Aspergillus fumigatus

• DOI: 10.1128/msphere.00076-23
• Publication Date: 2023-06-01T13:00:26Z
• Authors: Tim J.H. Baltussen; Norman van Rhijn; Jordy P.M. Coolen; Jan Dijksterhuis; Paul E. Verweij; Michael J. Bromley; Willem J.G. Melchers
• Keywords: Radboudumc 4: lnfectious Diseases and Global Health RIMLS: Radboud Institute for Molecular Life Sciences; hyphal development; Aspergillus fumigatus; Hyphae; Microbiology; Radboudumc 17: Women's cancers RIMLS: Radboud Institute for Molecular Life Sciences; QR1-502; All institutes and research themes of the Radboud University Medical Center; Aspergillus; germination; SltA; Humans; Aspergillosis; transcriptional regulation; Radboudumc 4: lnfectious Diseases and Global Health RIHS: Radboud Institute for Health Sciences; Research Article; Transcription Factors

ABSTRACT Germination of inhaled Aspergillus fumigatus conidia is a necessary sequitur for infection. starts with the breaking dormancy, which initiated by an increase cellular perimeter in process termed isotropic growth. This swelling phase followed polarized growth, resulting formation germ tube. The multinucleate tubular cells exhibit tip growth from hyphae, after lateral branches emerge to form mycelial network. regulatory mechanisms governing conidial germination are not well defined. In this study, we identified novel role transcription factor SltA orchestration and hyphal development. Conidia lacking sltA fail appropriately regulate begin swell earlier subsequently switch faster. Additionally, development distorted ∆ isolate as hyphae hyper-branching wider, show branching at apical tip. more tolerant cell wall stressors on minimal medium compared wild-type (WT) strain. A transcriptome analysis different stages early was carried out assess SltA. Null mutants generated three most dysregulated genes showed rapid tube emergence. Distinct phenotype observed , these strains lacked defects but switched Here, characterize describe several regulon SltA, highlighting complex nature germination. IMPORTANCE main human fungal pathogen causing aspergillosis. For fungus, azoles commonly used antifungal drugs treatment However, prevalence azole resistance alarmingly increasing linked elevated mortality. crucial within its asexual life cycle plays critical during infection host. Precluding could be promising strategy considering spp. pathogenicity. identify appropriate maintenance germination, Three were also essential conidia. With expanding knowledge morphotypes, advances can made toward potential anti-germination targets therapy.