Developmental Decisions in Aspergillus nidulans
The filamentous fungi (fungi) comprise a universal group of heterotrophic eukaryotic microorganisms living as saprophytes, parasites, or symbionts. Throughout the life cycle, in response to the various external and internal cues, fungi constantly make a decision between vegetative growth and (morphological and chemical) development. The basis for fungal vegetative growth is the continued and coordinated expansion of a series of fungal cell tips into a linear or complex structure. When conditions are met, fungi differentiate into a variety of structures including asexual and sexual spores, which are the effective means of genome protection, survival, and propagation. Spores are also the primary means for infecting host organisms for many human and plant pathogenic fungi. Among fungi, the genus Aspergillus represents the most widespread species in our environment that all reproduce asexually by forming long chains of conidiospores (or conidia) radiating from a central structure known as a conidiophore. The genetic model fungus Aspergillus nidulans has served as an excellent system for studying various biological questions, primarily due to the ease of genetic analysis through meiotic (sexual) recombination and the development of sophisticated molecular tools. These properties have provided a better understanding of the mechanisms controlling growth, development, secondary metabolism, and other aspects of cell biology in fungi. Here, we summarize our current understanding of the mechanisms of making asexual and sexual developmental decision in A. nidulans and present simple models.
KeywordsDevelopment Competence Conidiation Sexual fruiting Cleistothecia Aspergillus nidulans
The work by HSP and MJK was supported by the National Research Foundation of Korea (NRF) grant to HSP funded by the Korean government (MSIP: No. 2016010945). The work by KHH was supported by the Intelligent Synthetic Biology Center of Global Frontier Projects (2015M3A6A8065838) and by Basic Science Research Program through NRF (NRF-2017R1D1A3B06035312) funded by Korean government. The work by MKL and JHY was supported by the Intelligent Synthetic Biology Center of Global Frontier Project (2011-0031955) funded by the Ministry of Education, Science and Technology grants.
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