Structural insights into microtubule binding by dynein motors

Date

Mar 5, 2020

Time

3:00 PM - 4:00 PM

Speaker

Sam Lacey

Affiliation

MRC Laboratory of Molecular Biology, Cambridge, UK

Language

en

Main Topic

Biologie

Host

Gaia Pigino

Description

Dyneins are motor proteins responsible for transport in the cytoplasm and the beating of axonemes in cilia and flagella. They bind and release microtubules via a compact microtubule-binding domain (MTBD) at the end of a coiled-coil stalk. I will present cryo-EM structures of microtubules decorated with the MTBDs of cytoplasmic dynein-1 and axonemal dynein DNAH7, as well as a new workflow to process pseudosymmetrical filaments in Relion. These structures demonstrate that dyneins control their affinity for microtubules through the movement of a single helix. The DNAH7 MTBD contains an 18-residue insertion, found in many axonemal dyneins, that contacts the adjacent protofilament in our structures. We observe that DNAH7, but not dynein-1, induces large distortions in the microtubule cross-sectional curvature. These findings suggest that axonemal dyneins have developed an additional way to influence their microtubule track and control the ciliary beat.

Last modified: Mar 6, 2020, 12:09:26 AM