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5ood is a 5 chain structure with sequence from Oryctolagus cuniculus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[ACTS_RABIT] Actins are highly conserved proteins that are involved in various types of cell motility and are ubiquitously expressed in all eukaryotic cells.
Publication Abstract from PubMed
The function of actin is coupled to the nucleotide bound to its active site. ATP hydrolysis is activated during polymerization; a delay between hydrolysis and inorganic phosphate (Pi) release results in a gradient of ATP, ADP-Pi and ADP along actin filaments (F-actin). Actin-binding proteins can recognize F-actin's nucleotide state, using it as a local 'age' tag. The underlying mechanism is complex and poorly understood. Here we report six high-resolution cryo-EM structures of F-actin from rabbit skeletal muscle in different nucleotide states. The structures reveal that actin polymerization repositions the proposed catalytic base, His161, closer to the gamma-phosphate. Nucleotide hydrolysis and Pi release modulate the conformational ensemble at the periphery of the filament, thus resulting in open and closed states, which can be sensed by coronin-1B. The drug-like toxin jasplakinolide locks F-actin in an open state. Our results demonstrate in detail how ATP hydrolysis links to F-actin's conformational dynamics and protein interaction.
Structural transitions of F-actin upon ATP hydrolysis at near-atomic resolution revealed by cryo-EM.,Merino F, Pospich S, Funk J, Wagner T, Kullmer F, Arndt HD, Bieling P, Raunser S Nat Struct Mol Biol. 2018 Jun;25(6):528-537. doi: 10.1038/s41594-018-0074-0. Epub, 2018 Jun 4. PMID:29867215[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
