Unknown

Dataset Information

0

Tracking UNC-45 chaperone-myosin interaction with a titin mechanical reporter.


ABSTRACT: Myosins are molecular motors that convert chemical energy into mechanical work. Allosterically coupling ATP-binding, hydrolysis, and binding/dissociation to actin filaments requires precise and coordinated structural changes that are achieved by the structurally complex myosin motor domain. UNC-45, a member of the UNC-45/Cro1/She4p family of proteins, acts as a chaperone for myosin and is essential for proper folding and assembly of myosin into muscle thick filaments in vivo. The molecular mechanisms by which UNC-45 interacts with myosin to promote proper folding of the myosin head domain are not known. We have devised a novel approach, to our knowledge, to analyze the interaction of UNC-45 with the myosin motor domain at the single molecule level using atomic force microscopy. By chemically coupling a titin I27 polyprotein to the motor domain of myosin, we introduced a mechanical reporter. In addition, the polyprotein provided a specific attachment point and an unambiguous mechanical fingerprint, facilitating our atomic force microscopy measurements. This approach enabled us to study UNC-45-motor domain interactions. After mechanical unfolding, the motor domain interfered with refolding of the otherwise robust I27 modules, presumably by recruiting them into a misfolded state. In the presence of UNC-45, I27 folding was restored. Our single molecule approach enables the study of UNC-45 chaperone interactions with myosin and their consequences for motor domain folding and misfolding in mechanistic detail.

SUBMITTER: Kaiser CM 

PROVIDER: S-EPMC3341559 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

altmetric image

Publications

Tracking UNC-45 chaperone-myosin interaction with a titin mechanical reporter.

Kaiser Christian M CM   Bujalowski Paul J PJ   Ma Liang L   Anderson John J   Epstein Henry F HF   Oberhauser Andres F AF  

Biophysical journal 20120501 9


Myosins are molecular motors that convert chemical energy into mechanical work. Allosterically coupling ATP-binding, hydrolysis, and binding/dissociation to actin filaments requires precise and coordinated structural changes that are achieved by the structurally complex myosin motor domain. UNC-45, a member of the UNC-45/Cro1/She4p family of proteins, acts as a chaperone for myosin and is essential for proper folding and assembly of myosin into muscle thick filaments in vivo. The molecular mecha  ...[more]

Similar Datasets

| S-EPMC4225561 | biostudies-literature
| S-EPMC2064129 | biostudies-literature
| S-EPMC6803673 | biostudies-literature
| S-EPMC3060410 | biostudies-literature
| S-EPMC3549490 | biostudies-literature
| S-EPMC8521276 | biostudies-literature
| S-EPMC2043524 | biostudies-literature
| S-EPMC3143160 | biostudies-literature
| S-EPMC4129474 | biostudies-literature
| S-EPMC2133068 | biostudies-literature