4A7F

Structure of the Actin-Tropomyosin-Myosin Complex (rigor ATM 3)

Summary for 4A7F

• Entry DOI: 10.2210/pdb4a7f/pdb
• Related: 1ALM 1ATN 1EQY 1ESV 1H1V 1IJJ 1J6Z 1KXP 1LCU 1LKX 1LOT 1M8Q 1MA9 1MVW 1NWK 1O18 1O19 1O1A 1O1B 1O1C 1O1D 1O1E 1O1F 1O1G 1P8Z 1QZ5 1QZ6 1RDW 1RFQ 1RGI 1S22 1SQK 1T44 1UY5 1WUA 1Y64 2A3Z 2A40 2A41 2A42 2A5X 2ASM 2ASO 2ASP 2D1K 2D3E 2FF3 2FF6 2FXU 2TMA 2V51 2V52 2VCP 2VYP 2W49 2W4U 2Y83 2YJE 2YJF 4A7H 4A7L 4A7N
• EMDB information: 1987 1988 1989 1990
• Descriptor: ACTIN, ALPHA SKELETAL MUSCLE, TROPOMYOSIN 1 ALPHA, MYOSIN IE HEAVY CHAIN, ... (5 entities in total)
• Functional Keywords: structural protein-hydrolase complex, structural protein, cytoskeleton, contractile filament, motor activity, myosin binding, actin binding, atp catabolic process, rigor state, structural protein/hydrolase
• Biological source: ORYCTOLAGUS CUNICULUS (RABBIT); More
• Cellular location: Cytoplasm, cytoskeleton: P68135 P58772
• Total number of polymer chains: 10
• Total formula weight: 480951.73

Authors

Behrmann, E.,Mueller, M.,Penczek, P.A.,Mannherz, H.G.,Manstein, D.J.,Raunser, S. (deposition date: 2011-11-14, release date: 2012-08-01, Last modification date: 2025-04-09)

Primary citation

Behrmann, E.,Muller, M.,Penczek, P.A.,Mannherz, H.G.,Manstein, D.J.,Raunser, S.
Structure of the Rigor Actin-Tropomyosin-Myosin Complex.
Cell(Cambridge,Mass.), 150:327-, 2012

PubMed Abstract: Regulation of myosin and filamentous actin interaction by tropomyosin is a central feature of contractile events in muscle and nonmuscle cells. However, little is known about molecular interactions within the complex and the trajectory of tropomyosin movement between its "open" and "closed" positions on the actin filament. Here, we report the 8 Å resolution structure of the rigor (nucleotide-free) actin-tropomyosin-myosin complex determined by cryo-electron microscopy. The pseudoatomic model of the complex, obtained from fitting crystal structures into the map, defines the large interface involving two adjacent actin monomers and one tropomyosin pseudorepeat per myosin contact. Severe forms of hereditary myopathies are linked to mutations that critically perturb this interface. Myosin binding results in a 23 Å shift of tropomyosin along actin. Complex domain motions occur in myosin, but not in actin. Based on our results, we propose a structural model for the tropomyosin-dependent modulation of myosin binding to actin.

PubMed: 22817895
DOI: 10.1016/J.CELL.2012.05.037

Experimental method

ELECTRON MICROSCOPY (7.7 Å)