| Title | Cargo binding induces dimerization of myosin VI. | | Author(s) | Phichith D, Travaglia M, Yang Z, Liu X, Zong AB, Safer D, Sweeney HL | | Institution | Departments of Physiology and Cell and Developmental Biology and the Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, 3700 Hamilton Walk, Philadelphia, PA 19104-6085. | | Source | Proc Natl Acad Sci U S A 2009 Sep 28. | | Abstract | Although myosin VI has properties that would allow it to function optimally as a dimer, full-length myosin VI exists as a monomer in isolation. Based on the ability of myosin VI monomers to dimerize when held in close proximity, we postulated that cargo binding normally regulates dimerization of myosin VI. We tested this hypothesis by expressing a known dimeric cargo adaptor protein of myosin VI, optineurin, and the myosin VI-binding segment from a monomeric cargo adaptor protein, Dab2. In the presence of these adaptor proteins, full-length myosin VI has ATPase properties of a dimer, appears as a dimer in electron micrographs, and moves processively on actin filaments. The results support a model in which cargo binding exposes internal dimerization sequences within full-length myosin VI. Because, unexpectedly, a monomeric fragment of Dab2 triggers dimerization, it would appear that myosin VI is designed to function as a dimer in cells. | | Language | ENG | | Pub Type(s) | JOURNAL ARTICLE
| | PubMed ID | 19805065 |
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