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arXiv · 1905.11036

Cooperativity transitions driven by higher-order oligomer formations in ligand-induced receptor dimerization

Masaki Watabe·Satya N. V. Arjunan·Wei Xiang Chew·Kazunari Kaizu·Koichi Takahashi
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Abstract

While cooperativity in ligand-induced receptor dimerization has been linked with receptor-receptor couplings via minimal representations of physical observables, effects arising from higher-order oligomer (e.g., trimer and tetramer) formations of unobserved receptors have received less attention. Here, we propose a dimerization model of ligand-induced receptors in multivalent form representing physical observables under basis vectors of various aggregated receptor-states. Our simulations of multivalent models not only reject Wofsy-Goldstein parameter conditions for cooperativity, but show higher-order oligomer formations can shift cooperativity from positive to negative.

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Masaki Watabe, Satya N. V. Arjunan, Wei Xiang Chew, Kazunari Kaizu, Koichi Takahashi. 2019-05-27. Cooperativity transitions driven by higher-order oligomer formations in ligand-induced receptor dimerization. https://doi.org/10.1103/physreve.100.062407

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