Skip to main content

A mutant heterodimeric myosin with one inactive head generates maximal displacement

Kad, Neil M, Rovner, Arthur S, Fagnant, Patricia M, Joel, Peteranne B, Kennedy, Guy G, Patlak, Joseph B, Warshaw, David M, Trybus, Kathleen M (2003) A mutant heterodimeric myosin with one inactive head generates maximal displacement. The Journal of cell biology, 162 (3). pp. 481-488. ISSN 0021-9525. E-ISSN 1540-8140. (doi:10.1083/jcb.200304023) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided) (KAR id:42950)

The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided.
Official URL
http://dx.doi.org/10.1083/jcb.200304023

Abstract

Each of the heads of the motor protein myosin II is capable of supporting motion. A previous report showed that double-headed myosin generates twice the displacement of single-headed myosin (Tyska, M.J., D.E. Dupuis, W.H. Guilford, J.B. Patlak, G.S. Waller, K.M. Trybus, D.M. Warshaw, and S. Lowey. 1999. Proc. Natl. Acad. Sci. USA. 96:4402-4407). To determine the role of the second head, we expressed a smooth muscle heterodimeric heavy meromyosin (HMM) with one wild-type head, and the other locked in a weak actin-binding state by introducing a point mutation in switch II (E470A). Homodimeric E470A HMM did not support in vitro motility, and only slowly hydrolyzed MgATP. Optical trap measurements revealed that the heterodimer generated unitary displacements of 10.4 nm, strikingly similar to wild-type HMM (10.2 nm) and approximately twice that of single-headed subfragment-1 (4.4 nm). These data show that a double-headed molecule can achieve a working stroke of approximately 10 nm with only one active head and an inactive weak-binding partner. We propose that the second head optimizes the orientation and/or stabilizes the structure of the motion-generating head, thereby resulting in maximum displacement.

Item Type: Article
DOI/Identification number: 10.1083/jcb.200304023
Subjects: Q Science
Divisions: Divisions > Division of Natural Sciences > Biosciences
Depositing User: Neil Kad
Date Deposited: 15 Sep 2014 19:03 UTC
Last Modified: 16 Nov 2021 10:17 UTC
Resource URI: https://kar.kent.ac.uk/id/eprint/42950 (The current URI for this page, for reference purposes)
Kad, Neil M: https://orcid.org/0000-0002-3491-8595
  • Depositors only (login required):