Editing Conidium (section)

=== Germination in ''Aspergillus'' ===
As evidenced by recent literature, conidia germination of ''Aspergillus'', a common mold, specifically is of interest. ''Aspergillus'' is not only a familiar fungus found across various different settings in the world, but it poses a danger for immunocompromised individuals, as inhaled ''Aspergillus'' conidia could germinate inside the respiratory tract and cause aspergillosis, a form of pulmonary infection, and continual developments of aspergillosis such as new risk groups and the resistance against antifungal drugs.

==== Stages of Germination: Dormancy ====
Germination in ''Aspergillus'' follows a sequence of three different stages: dormancy, isotropic growth, and polarized growth. The dormant conidia are able to germinate even after an year of remaining at room temperature, due to their resilient intracellular and extracellular characteristics, which enable them to undergo harsh conditions like dehydration, variation in osmotic pressure, oxidation, and temperature, and change in UV exposure and acidity levels. These abilities of the dormant conidia are dictated by a few central regulatory proteins, which are the main drivers of the conidia and conidiophore formation. One of these proteins, the developmental regulatory protein wetA, has been found to be particularly essential; in wetA-defective mutants have reduced tolerance to external factors mentioned above, and exhibit weak synthesization of the conidial cell wall. In addition to these central regulators, some notable groups of genes/proteins include other regulatory proteins like the velvet regulator proteins, which contribute to fungal growth, and other molecules that target specific unfavorable intra and extracellular conditions, like heat shock proteins. <ref name=":0">{{Cite journal |last1=Baltussen |first1=Tim J. H. |last2=Zoll |first2=Jan |last3=Verweij |first3=Paul E. |last4=Melchers |first4=Willem J. G. |date=2020-02-19 |title=Molecular Mechanisms of Conidial Germination in Aspergillus spp |journal=Microbiology and Molecular Biology Reviews |language=en |volume=84 |issue=1 |doi=10.1128/MMBR.00049-19 |issn=1092-2172 |pmc=6903801 |pmid=31801804}}</ref><ref name=":1">{{Citation |last=Osherov |first=Nir |title=Conidial Germination in Aspergillus fumigatus |date=2014-04-09 |work=Aspergillus fumigatus and Aspergillosis |pages=131–142 |editor-last=Latgé |editor-first=Jean-Paul |url=http://doi.wiley.com/10.1128/9781555815523.ch10 |access-date=2024-05-11 |place=Washington, DC, USA |publisher=ASM Press |language=en |doi=10.1128/9781555815523.ch10 |isbn=978-1-68367-138-1 |editor2-last=Steinbach |editor2-first=William J.|url-access=subscription }}</ref>

==== Stages of Germination: Isotropic and Polarized Growth ====
The phases following dormancy include isotropic growth, in which increased intracellular osmotic pressure and water uptake causes swelling of the conidia and increased cellular diameter, and polarized growth, in which the swelling from isotropic growth directs the growth to one side of the cell, and leads to the formation of a germ tube. First, however, the conidia must go through the stage of breaking dormancy. In some species of Aspergillus, dormancy is broken when the dormant conidia is introduced to a carbon source in the presence of water and air, while in other species, the mere presence of glucose is enough to trigger it. The dense outer layer of the dormant conidia is shed and the growth of the hyphae cells begins, which has a significantly different composition compared to the dormant conidia cell. Breaking of dormancy involves transcription, but not translation; protein synthesis inhibitors prevent isotropic growth, while DNA and RNA synthesis inhibitors do not, and the start of breaking of dormancy is accompanied by and increase in transcripts for genes for biosynthesis of proteins, and immediate protein synthesis. Following the expansion of the cell via isotropic growth, studies have observed many new proteins emerging from the processes in the breaking of dormancy and transcripts associated with remodeling of the cell wall, suggesting that remodeling of the cell wall is a central process during isotropic growth. In the polarized growth stage, upregulated and overexpressed proteins and transcripts included ones involved in synthesis of chitin (a major component of the fungal cell wall), mitosis and DNA processing, remodeling of cell morphology, and ones in germ tube formation pertaining to infection and virulence factors. <ref name=":0" /><ref name=":1" />