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Quantitative Analysis of Aspergillus nidulans Growth Rate using Live Microscopy and Open-Source Software
Published on: July 24, 2021
Transcriptome changes initiated by carbon starvation in Aspergillus nidulans
Melinda Szilágyi1, Márton Miskei1, Zsolt Karányi2
1Department of Microbial Biotechnology and Cell Biology, University of Debrecen, Egyetem tér 1, 4032 Debrecen, Hungary.
Microbiology (Reading, England)
|November 17, 2012
Summary
Microorganisms adapt to carbon starvation by activating complex stress responses. This involves shifting towards degradation pathways, producing enzymes, and enhancing survival mechanisms.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Carbon starvation is a prevalent stress impacting microbial life in natural and industrial settings.
- The carbon starvation stress response (CSSR) regulates critical cellular processes like programmed cell death, reproduction, secondary metabolite production, and extracellular hydrolase formation in fungi.
Purpose of the Study:
- To elucidate the physiological events and transcriptomic changes associated with the carbon starvation stress response (CSSR).
- To understand the molecular mechanisms fungi employ for long-term survival under nutrient-deprived conditions.
Main Methods:
- Utilized DNA microarray analyses to assess global gene expression changes.
- Employed real-time reverse transcription PCR (rRT-PCR) for quantitative validation of gene expression for 99 selected genes.
Main Results:
- Carbon starvation induced significant and complex alterations in the fungal transcriptome.
- Upregulation of genes involved in protein synthesis and the unfolded protein stress response was observed.
- Metabolic balance shifted towards degradation, evidenced by increased cell wall, carbohydrate, lipid, and nitrogen metabolism breakdown, alongside enhanced hydrolytic enzyme production and macroautophagy.
- Induced synthesis of secondary metabolites and various degrading enzymes (antifungal, bacterial cell wall) suggests ecological impact on surrounding microorganisms.
- Increased production of extracellular and vacuolar enzymes highlighted the heightened importance of the endoplasmic reticulum during CSSR.
Conclusions:
- Fungal CSSR involves a coordinated shift towards degradation pathways to liberate nutrients for long-term survival.
- Carbon-starving fungi can significantly influence their microbial environment through the release of enzymes and secondary metabolites.
- The endoplasmic reticulum plays a crucial role in managing the increased enzyme production during carbon starvation.
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