Shaft Function of Kinesin-1's α4 Helix in the Processive Movement.
Cell Mol Bioeng
; 12(4): 345-354, 2019 Aug.
Article
em En
| MEDLINE
| ID: mdl-31719918
ABSTRACT
INTRODUCTION:
Kinesin-1 motor is a molecular walking machine constructed with amino acids. The understanding of how those structural elements play their mechanical roles is the key to the understanding of kinesin-1 mechanism.METHODS:
Using molecular dynamics simulations, we investigate the role of a helix structure, α4 (also called switch-II helix), of kinesin-1's motor domain in its processive movement along microtubule.RESULTS:
Through the analysis of the structure and the interactions between α4 and the surrounding residues in different nucleotide-binding states, we find that, mechanically, this helix functions as a shaft for kinesin-1's motor-domain rotation and, structurally, it is an amphipathic helix ensuring its shaft functioning. The hydrophobic side of α4 consists strictly of hydrophobic residues, making it behave like a lubricated surface in contact with the core ß-sheet of kinesin-1's motor domain. The opposite hydrophilic side of α4 leans firmly against microtubule with charged residues locating at both ends to facilitate its positioning onto the intra-tubulin groove.CONCLUSIONS:
The special structural feature of α4 makes for an effective reduction of the conformational work in kinesin-1's force generation process.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Cell Mol Bioeng
Ano de publicação:
2019
Tipo de documento:
Article