PDBsum entry 4pjj

Motor protein

PDB id: 4pjj

Contents

Protein chains

743 a.a.

146 a.a.

Ligands

ADP

PO4 ×2

GOL ×2

Metals

_CA ×2

_MG

Waters ×354

PDB id:

4pjj

Name:

Motor protein

Title:

Myosin vi (md-insert2-cam, delta-insert1) post-rigor state - long soaking with po4

Structure:

Unconventional myosin-vi. Chain: a. Engineered: yes. Calmodulin. Chain: b. Synonym: cam. Engineered: yes

Source:

Sus scrofa. Pig. Organism_taxid: 9823. Gene: myo6. Expressed in: spodoptera frugiperda. Expression_system_taxid: 7108. Expression_system_cell_line: sf9. Drosophila melanogaster. Fruit fly.

Resolution:

2.40Å R-factor: 0.174 R-free: 0.207

Authors:

T.Isabet,H.Benisty,P.Llinas,H.L.Sweeney,A.Houdusse

Key ref:

P.Llinas et al. (2015). How actin initiates the motor activity of Myosin. Dev Cell, 33, 401-412. PubMed id: 25936506 DOI: 10.1016/j.devcel.2015.03.025

Date:

12-May-14 Release date: 29-Apr-15

Protein chain

F1RQI7  (F1RQI7_PIG) -  Unconventional myosin-VI from Sus scrofa

Seq: 1266 a.a.

Struc: 743 a.a.*

Protein chain

P62152  (CALM_DROME) -  Calmodulin from Drosophila melanogaster

Seq: 149 a.a.

Struc: 146 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

DOI no: 10.1016/j.devcel.2015.03.025

Dev Cell 33:401-412 (2015)

PubMed id: 25936506

How actin initiates the motor activity of Myosin.

P.Llinas, T.Isabet, L.Song, V.Ropars, B.Zong, H.Benisty, S.Sirigu, C.Morris, C.Kikuti, D.Safer, H.L.Sweeney, A.Houdusse.

ABSTRACT

Fundamental to cellular processes are directional movements driven by molecular motors. A common theme for these and other molecular machines driven by ATP is that controlled release of hydrolysis products is essential for using the chemical energy efficiently. Mechanochemical transduction by myosin motors on actin is coupled to unknown structural changes that result in the sequential release of inorganic phosphate (Pi) and MgADP. We present here a myosin structure possessing an actin-binding interface and a tunnel (back door) that creates an escape route for Pi with a minimal rotation of the myosin lever arm that drives movements. We propose that this state represents the beginning of the powerstroke on actin and that Pi translocation from the nucleotide pocket triggered by actin binding initiates myosin force generation. This elucidates how actin initiates force generation and movement and may represent a strategy common to many molecular machines.