Cells Dying via the AP-3 Complex-Dependent Regulated Death Pathway Support the Surviving Cells under Amino Acid
Svyatoslav S Sokolov1, Ekaterina A Smirnova2, Natalia A Kireeva2
1Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. sviatoslav.sokolov@gmail.com.
Biochemistry. Biokhimiia
|August 31, 2025
Summary
Heating yeast cells to 52°C triggers a programmed death pathway that releases nutrients, supporting surviving cells during amino acid starvation. This process, dependent on lysosomal membrane decomposition, aids nutrient-deprived yeast populations.
Area of Science:
- Cell Biology
- Microbiology
- Biochemistry
Background:
- Unicellular organisms can undergo programmed cell death during starvation to support surviving populations.
- Heating Saccharomyces cerevisiae yeast cells to 51°C induces a specific cell death pathway involving lysosomal and plasma membrane breakdown.
Purpose of the Study:
- To investigate the role of heat-induced cell death in nutrient provision for starving yeast.
- To determine if the lysosomal membrane decomposition pathway is essential for releasing growth-promoting substances.
Main Methods:
- Yeast cell treatments: heating at 52°C, boiling, and using AP-3 complex deficient mutants.
- Assessing growth stimulation of living yeast cells under amino acid deficiency.
- Spectrophotometry and mass spectrometry analysis of the cell medium.
Main Results:
- Yeast cells killed by heating to 52°C significantly stimulated the growth of living cells under amino acid deficiency.
- Mutant cells lacking the AP-3 complex, unable to degrade the lysosomal membrane, did not support growth.
- Medium from 52°C heated cells contained substances absorbing at short wavelengths, suggesting nucleic acid hydrolysis products.
Conclusions:
- Heat-induced cell death in yeast, specifically via lysosomal membrane hydrolysis, releases compounds that support surviving cells during nitrogen starvation.
- The AP-3 complex is crucial for this nutrient-sharing mechanism.
- Nucleic acid hydrolysis products are likely responsible for promoting the growth of surviving yeast cells.
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