Subpopulations of hyphae secrete proteins or resist heat stress in Aspergillus oryzae colonies.
Environ Microbiol. 2019 Nov 17;:
Authors: Tegelaar M, Bleichrodt RJ, Nitsche B, Ram AFJ, Wösten HAB
Hyphae at the outer part of colonies of Aspergillus niger and Aspergillus oryzae are heterogeneous with respect to transcriptional and translational activity. This heterogeneity is maintained by Woronin body mediated closure of septal pores that block inter-hyphal mixing of cytoplasm. Indeed, heterogeneity between hyphae is abolished in ΔhexA strains that lack Woronin bodies. The sub-population of hyphae with high transcriptional and translational activity secretes enzymes that degrade the substrate resulting in breakdown products that serve as nutrients. The role of hyphae with low transcriptional and translational activity was not yet known. Here we show that this subpopulation is more resistant to environmental stress in A. oryzae, in particular to temperature stress, when compared to hyphae with high transcriptional and translational activity. In contrast, all hyphae of the ΔhexA strain of A. oryzae were sensitive to heat stress explained by the reduced heterogeneity in this strain. Together, we show that different subpopulations of hypha secrete proteins and resist heat stress showing the complexity of a fungal mycelium. This article is protected by copyright. All rights reserved.
PMID: 31736205 [PubMed – as supplied by publisher]