Entropy-driven genome organization.

Davide Marenduzzo; Cristian Micheletti; Peter R Cook

doi:10.1529/biophysj.105.077685

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PubMed · 16500976

Entropy-driven genome organization.

Davide Marenduzzo·Cristian Micheletti·Peter R Cook

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Abstract

DNA and RNA polymerases active on bacterial and human genomes in the crowded environment of a cell are modeled as beads spaced along a string. Aggregation of the large polymerizing complexes increases the entropy of the system through an increase in entropy of the many small crowding molecules; this occurs despite the entropic costs of looping the intervening DNA. Results of a quantitative cost/benefit analysis are consistent with observations that active polymerases cluster into replication and transcription "factories" in both pro- and eukaryotes. We conclude that the second law of thermodynamics acts through nonspecific entropic forces between engaged polymerases to drive the self-organization of genomes into loops containing several thousands (and sometimes millions) of basepairs.

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Computer Simulation DNA DNA-Directed DNA Polymerase DNA-Directed RNA Polymerases Entropy Genome Models, Chemical Models, Molecular Nucleic Acid Conformation Journal Article Research Support, Non-U.S. Gov't

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Davide Marenduzzo, Cristian Micheletti, Peter R Cook. 2006-02-24. Entropy-driven genome organization.. https://doi.org/10.1529/biophysj.105.077685

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