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2y83
From Proteopedia
Revision as of 10:38, 12 January 2022 by OCA (Talk | contribs)
2y83 is a 6 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 actin filament has clear polarity where one end, the pointed end, has a much slower polymerization and depolymerization rate than the other end, the barbed end. This intrinsic difference of the ends significantly affects all actin dynamics in the cell, which has central roles in a wide spectrum of cellular functions. The detailed mechanism underlying this difference has remained elusive, because high-resolution structures of the filament ends have not been available. Here, we present the structure of the actin filament pointed end obtained using a single particle analysis of cryo-electron micrographs. We determined that the terminal pointed end subunit is tilted towards the penultimate subunit, allowing specific and extra loop-to-loop inter-strand contacts between the two end subunits, which is not possible in other parts of the filament. These specific contacts prevent the end subunit from dissociating. For elongation, the loop-to-loop contacts also inhibit the incorporation of another actin monomer at the pointed end. These observations are likely to account for the less dynamic pointed end.
Structural basis for the slow dynamics of the actin filament pointed end.,Narita A, Oda T, Maeda Y EMBO J. 2011 Mar 4. PMID:21378753[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Narita A, Oda T, Maeda Y. Structural basis for the slow dynamics of the actin filament pointed end. EMBO J. 2011 Mar 4. PMID:21378753 doi:10.1038/emboj.2011.48
