title: Insights into dynein motor domain function from a 3.3-Å crystal structure.
abstract: Dyneins power the beating of cilia and flagella, transport various intracellular cargos and are necessary for mitosis. All dyneins have a ∼300-kDa motor domain consisting of a ring of six AAA+ domains. ATP hydrolysis in the AAA+ ring drives the cyclic relocation of a motile element, the linker domain, to generate the force necessary for movement. How the linker interacts with the ring during the ATP hydrolysis cycle is not known. Here we present a 3.3-Å crystal structure of the motor domain of Saccharomyces cerevisiae cytoplasmic dynein, crystallized in the absence of nucleotides. The linker is docked to a conserved site on AAA5, which is confirmed by mutagenesis as functionally necessary. Nucleotide soaking experiments show that the main ATP hydrolysis site in dynein (AAA1) is in a low-nucleotide affinity conformation and reveal the nucleotide interactions of the other three sites (AAA2, AAA3 and AAA4).
authors.affiliation: Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
authors.forename: Helgo
authors.initials: H
authors.lastname: Schmidt
authors.forename: Emma S
authors.initials: ES
authors.lastname: Gleave
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Carter
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004398:Dyneins / Q000737:chemistry* / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D009711:Nucleotides / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D009711:Nucleotides; D004398:Dyneins