4WYB

Structure of the Bud6 flank domain in complex with actin

Summary for 4WYB

• Entry DOI: 10.2210/pdb4wyb/pdb
• Descriptor: Actin, alpha skeletal muscle, Bud site selection protein 6, ADENOSINE-5'-TRIPHOSPHATE, ... (4 entities in total)
• Functional Keywords: nucleation promoting factor wh2 domain, formin, contractile protein-protein binding complex, contractile protein/protein binding
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Cellular location: Cytoplasm, cytoskeleton: P68135
• Total number of polymer chains: 24
• Total formula weight: 638218.45

Authors

Eck, M.J.,Park, E.,Zheng, W. (deposition date: 2014-11-17, release date: 2015-08-19, Last modification date: 2023-09-27)

Primary citation

Park, E.,Graziano, B.R.,Zheng, W.,Garabedian, M.,Goode, B.L.,Eck, M.J.
Structure of a Bud6/Actin Complex Reveals a Novel WH2-like Actin Monomer Recruitment Motif.
Structure, 23:1492-1499, 2015

PubMed Abstract: In budding yeast, the actin-binding protein Bud6 cooperates with formins Bni1 and Bnr1 to catalyze the assembly of actin filaments. The nucleation-enhancing activity of Bud6 requires both a "core" domain that binds to the formin and a "flank" domain that binds monomeric actin. Here, we describe the structure of the Bud6 flank domain in complex with actin. Two helices in Bud6(flank) interact with actin; one binds in a groove at the barbed end of the actin monomer in a manner closely resembling the helix of WH2 domains, a motif found in many actin nucleation factors. The second helix rises along the face of actin. Mutational analysis verifies the importance of these Bud6-actin contacts for nucleation-enhancing activity. The Bud6 binding site on actin overlaps with that of the formin FH2 domain and is also incompatible with inter-subunit contacts in F-actin, suggesting that Bud6 interacts only transiently with actin monomers during filament nucleation.

PubMed: 26118535
DOI: 10.1016/j.str.2015.05.015

Experimental method

X-RAY DIFFRACTION (3.493 Å)