Targeting allostery in the Dynein motor domain with small molecule inhibitors. Issue 10 (21st October 2021)

• Record Type: Journal Article
• Authors: Santarossa, Cristina C.; Mickolajczyk, Keith J.; Steinman, Jonathan B.; Urnavicius, Linas; Chen, Nan; Hirata, Yasuhiro; Fukase, Yoshiyuki; Coudray, Nicolas; Ekiert, Damian C.; Bhabha, Gira; Kapoor, Tarun M.
• Is Part Of: Cell chemical biology. Volume 28:Issue 10(2021)
• Page Start: 1460
• Page End: 1473.e15
• Publication Date: 2021-10-21
• Subjects: Dynein -- AAA ATPases -- cryo-EM -- X-ray crystallography -- motor proteins -- single molecule; Biochemistry -- Periodicals; 572.05
• DOI: 10.1016/j.chembiol.2021.04.024
• Languages: English
• ISSNs: 2451-9456

Abstract

Summary: Cytoplasmic dyneins are AAA (ATPase associated with diverse cellular activities) motor proteins responsible for microtubule minus-end-directed intracellular transport. Dynein's unusually large size, four distinct nucleotide-binding sites, and conformational dynamics pose challenges for the design of potent and selective chemical inhibitors. Here we use structural approaches to develop a model for the inhibition of a well-characterized S. cerevisiae dynein construct by pyrazolo-pyrimidinone-based compounds. These data, along with functional assays of dynein motility and mutagenesis studies, suggest that the compounds inhibit dynein by engaging the regulatory ATPase sites in the AAA3 and AAA4 domains, and not by interacting with dynein's main catalytic site in the AAA1 domain. A double Walker B mutation of the AAA3 and AAA4 sites substantially reduces enzyme activity, suggesting that targeting these regulatory domains is sufficient to inhibit dynein. Our findings reveal how chemical inhibitors can be designed to disrupt allosteric communication across dynein's AAA domains. Graphical abstract: Highlights: A chemical inhibitor of Saccharomyces cerevisiae dynein enables structural studies Structural data indicate that the inhibitor binds dynein's regulatory ATPase sites Blocking AAA3 and AAA4 sites in the motor protein can inhibit its activity Data provide a structural framework that can aid in inhibitor optimization Abstract : Santarossa et al. describe a pyrazolo-pyrimidinone-based compound that targets two regulatory AAA domains in dynein to block its motility. These data show that the AAA3 and AAA4 domains of dynein are druggable sites and provide a framework that can guide inhibitor optimization.