9GO5

CryoEM Reconstruction of Yeast ADP-Actin Filament at 2.5 A resolution.

Summary for 9GO5

• Entry DOI: 10.2210/pdb9go5/pdb
• EMDB information: 51491
• Descriptor: Actin, ADENOSINE-5'-DIPHOSPHATE, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: fibre, polymer, helical protein, motility, protein fibril
• Biological source: Saccharomyces cerevisiae (brewer's yeast)
• Total number of polymer chains: 5
• Total formula weight: 210935.26

Authors

Bullough, P.A.,Ayscough, K.R.,Lahiri, I.,Tzokov, S.B.,Stevenson, S.R. (deposition date: 2024-09-04, release date: 2025-01-22, Last modification date: 2025-03-19)

Primary citation

Stevenson, S.R.,Tzokov, S.B.,Lahiri, I.,Ayscough, K.R.,Bullough, P.A.
Cryo-EM reconstruction of yeast ADP-actin filament at 2.5 angstrom resolution. A comparison with vertebrate F-actin.
Structure, 33:435-442.e3, 2025

PubMed Abstract: The core component of the actin cytoskeleton is the globular protein G-actin, which reversibly polymerizes into filaments (F-actin). Budding yeast possesses a single actin that shares 87%-89% sequence identity with vertebrate actin isoforms. Previous structural studies indicate very close overlap of main-chain backbones. Intriguingly, however, substitution of yeast ACT1 with vertebrate β-cytoplasmic actin severely disrupts cell function and the substitution with a skeletal muscle isoform is lethal. Here we report a 2.5 Å structure of budding yeast F-actin. Previously unresolved side-chain information allows us to highlight four main differences in the comparison of yeast and vertebrate ADP F-actins: a more open nucleotide binding pocket; a more solvent exposed C-terminus; a rearrangement of inter-subunit binding interactions in the vicinity of the D loop and changes in the hydrogen bonding network in the vicinity of histidine 73 (yeast actin) and methyl-histidine 73 (vertebrate actin).

PubMed: 39798573
DOI: 10.1016/j.str.2024.12.008

Experimental method

ELECTRON MICROSCOPY (2.5 Å)