The novel spore-specific regulator SscA governsAspergillusconidiogenesis

Abstract

A major group of fungi produces asexual spores (conidia) for propagation and infection. Despite the critical role of conidia, the underlying mechanism of spore formation, integrity, and viability is not fully elucidated. In this study, we have identified and investigated the role of the spore-specific transcription factor (TF) SscA in three representativeAspergillusspecies. Comparative transcriptomic analyses have revealed that 25 TF encoding genes showed higher mRNA levels in conidia than in hyphae in three species. Functional and transcriptomic analyses of the 25 genes have identified SscA as a key TF for conidial formation, maturation, germination, integrity, amino acid production, and secondary metabolism inAspergillus nidulansconidia. Importantly, the roles of SscA are conserved in otherAspergillusspecies. Altogether, our study demonstrates that SscA is a novel spore-specific TF that governs production of intact and functional conidial formation inAspergillusspecies.