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Updated: Jun 6, 2026
08:54
Efficient Sporulation of Saccharomyces cerevisiae in a 96 Multiwell Format
Published on: September 17, 2016
Ultrastructural changes in Neurospora cells undergoing senescence induced by kalilo plasmids
Jin-Woo Bok1, Ken-Ichiro Ishida, Anthony J F Griffiths
1Department of Botany, University of British Columbia, 6270 University Blvd., Vancouver, V6T 1Z4 Canada.
Mycologia
|December 16, 2010
Summary
The kalilo plasmid induces senescence in N. crassa and N. intermedia by integrating into mitochondrial DNA. Cell death occurs via necrosis, not apoptosis, characterized by mitochondrial swelling and membrane disruption.
Area of Science:
- Molecular Biology
- Cell Biology
- Mycology
Background:
- The kalilo plasmid is known to induce senescence in N. crassa and N. intermedia.
- Mitochondrial DNA integration by plasmids can impact cellular function and aging.
Purpose of the Study:
- To investigate the specific cell death pathway triggered by the kalilo plasmid in N. crassa and N. intermedia.
- To differentiate between apoptotic and necrotic cell death mechanisms.
Main Methods:
- Light and transmission electron microscopy were used to examine cellular morphology.
- DNA analysis was performed to detect fragmentation patterns.
- Juvenile and senescent subcultures of multiple strains were analyzed.
Main Results:
- No evidence of apoptosis was observed, including lack of cytoplasmic shrinkage, apoptotic bodies, or DNA fragmentation.
- Swollen mitochondria lacking cristae and containing amorphous inclusions were prevalent.
- Disruption of nuclear and mitochondrial membranes indicated a necrotic cell death process.
Conclusions:
- The kalilo plasmid induces a necrotic mode of cell death in N. crassa and N. intermedia.
- Senescence triggered by mitochondrial DNA insertion does not involve classical apoptotic pathways.
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