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Stochastic Model of Maturation and Vesicular Exchange in Cellular Organelles.

ABSTRACT: The dynamical organization of membrane-bound organelles along intracellular transport pathways relies on vesicular exchange between organelles and on the maturation of the organelle's composition by enzymatic reactions or exchange with the cytoplasm. The relative importance of each mechanism in controlling organelle dynamics remains controversial, in particular for transport through the Golgi apparatus. Using a stochastic model, we identify two classes of dynamical behavior that can lead to full maturation of membrane-bound compartments. In the first class, maturation corresponds to the stochastic escape from a steady state in which export is dominated by vesicular exchange, and is very unlikely for large compartments. In the second class, it occurs in a quasi-deterministic fashion and is almost size independent. Whether a system belongs to the first or second class is largely controlled by homotypic fusion.

SUBMITTER: Vagne Q

PROVIDER: S-EPMC5984994 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Stochastic Model of Maturation and Vesicular Exchange in Cellular Organelles.

Vagne Quentin Q Sens Pierre P

Biophysical journal 20180201 4

The dynamical organization of membrane-bound organelles along intracellular transport pathways relies on vesicular exchange between organelles and on the maturation of the organelle's composition by enzymatic reactions or exchange with the cytoplasm. The relative importance of each mechanism in controlling organelle dynamics remains controversial, in particular for transport through the Golgi apparatus. Using a stochastic model, we identify two classes of dynamical behavior that can lead to full ...[more]

PMID: 29490254

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Dataset Information

Stochastic Model of Maturation and Vesicular Exchange in Cellular Organelles.

Publications

Stochastic Model of Maturation and Vesicular Exchange in Cellular Organelles.

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