Peroxisomes in yeast ageing

Sanjeev Kumar

Research output: ThesisThesis fully internal (DIV)

1073 Downloads (Pure)


Ageing is characterized by the progressive decline in cellular functions that eventually leads to death. In human, ageing is associated with several age-related diseases such as cancer, cardiovascular disorders and neurodegenerative diseases. Over the years, research performed in several simpler short-lived organisms has contributed immensely to our current understanding of ageing. In this thesis we used yeast as a model organism to understand the significance of peroxisomes in ageing. Peroxisomes are cell organelles that - together with mitochondria - are the major producers of reactive oxygen species, molecules that damage vital cellular macromolecules and hence contribute to stress.
Using fluorescence microscopy we showed that in yeast cells peroxisomes of different age are present. During cell division the older organelles are kept by the mother cell whereas the daughter cell gets the newer ones.
We also studied the significance of peroxisomal metabolism in yeast ageing. We found that growth of cells on substrates that are metabolized by peroxisomal enzymes resulted in lifespan extension. For methylamine we showed that its oxidation in peroxisomes provides additional energy to cells that leads to a longer lifespan.
Previously it was reported that deletion of the gene DNM1, which causes a block in mitochondrial fission, results in lifespan extension of yeast cells. However, Dnm1 is also involved in peroxisomal fission. Interestingly, our data shows that the block in peroxisome fission, and not mitochondrial fission, is the primary cause of the observed lifespan extension of yeast dnm1 cells.
Original languageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • University of Groningen
  • van der Klei, Ida, Supervisor
Award date4-Dec-2015
Place of Publication[Groningen]
Print ISBNs978-94-6182-631-2
Electronic ISBNs978-90-367-8451-1
Publication statusPublished - 2015

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