Single-Cell Biophysics: Measurement, Modulation, and Modeling

Single-Cell Biophysics: Measurement, Modulation, and Modeling

Poster Abstracts

7-POS Board 4 Mathematical Modeling of Mitochondrial Quality Control in Mitochondiral Life Cycle and its Role in Aging Chen Chang 1 , Yi-Ping Ho 2 , An-Chi Wei 1 . 1 National Taiwan University, Taipei City, Taiwan, 2 The Chinese University of Hong Kong, Sha Tin, Hong Kong. Mitochondria play an important role in cell viability, for providing most of the energy in cells. The dynamics and quality of these organelles are therefore critical for cell activities. Previous research has shown that mitochondria have two different morphologies, a network and an individual status, and that mitochondria, throughout their life cycles, constantly enter and reenter each of these statuses during fusion and fission events. This suggests that a combination of fusion, fission, and mitophagy events may serve as a mechanism of mitochondrial quality control. The increasing interest in the mitochondria life cycle has led to more attempts to create mathematical model of fusion/fission/mitophagy events. Recent modellings have demonstrated that a favorable fusion and fission balance may inhibit the clonal expansion of damaged mitochondrial DNA and may prove critical to the maintenance of mitochondrial quality. This research implements mathematical modelling of the mitochondrial life cycle that accounts for several new findings regarding this cycle. In this stochastic model, the quality and size of individual mitochondria are described in terms of mitochondrial nucleic content. Simulations of fusion/fission/mitophagy are optimized to match the different cell statuses in different life periods. This model also considers the factor of spatial distribution of mitochondria within cells. We also assume that the event of mitophagy, followed by fission, is not random but is mediated to create an unbalanced distribution of mitochondrial contents. Implementations of a dynamic status then allow us the exploration of the role of fusion/fission/mitophagy in ageing, and its effects on the cell division, from a bio-energetic perspective. Our ultimate goal is gain greater insight into the differences in the dynamical equilibrium of fusion/fission and its relevance to cell survival.

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