Structure of the γ-tubulin ring complex-capped microtubule.

Nat Struct Mol Biol

Laboratory of Chemistry and Cell Biology, The Rockefeller University, New York, NY, USA.

Published: July 2024

Microtubules are composed of α-tubulin and β-tubulin dimers positioned head-to-tail to form protofilaments that associate laterally in varying numbers. It is not known how cellular microtubules assemble with the canonical 13-protofilament architecture, resulting in micrometer-scale α/β-tubulin tracks for intracellular transport that align with, rather than spiral along, the long axis of the filament. We report that the human ~2.3 MDa γ-tubulin ring complex (γ-TuRC), an essential regulator of microtubule formation that contains 14 γ-tubulins, selectively nucleates 13-protofilament microtubules. Cryogenic electron microscopy reconstructions of γ-TuRC-capped microtubule minus ends reveal the extensive intra-domain and inter-domain motions of γ-TuRC subunits that accommodate luminal bridge components and establish lateral and longitudinal interactions between γ-tubulins and α-tubulins. Our structures suggest that γ-TuRC, an inefficient nucleation template owing to its splayed conformation, can transform into a compacted cap at the microtubule minus end and set the lattice architecture of cellular microtubules.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11257807PMC
http://dx.doi.org/10.1038/s41594-024-01264-zDOI Listing

Publication Analysis

Top Keywords

γ-tubulin ring
8
cellular microtubules
8
microtubule minus
8
structure γ-tubulin
4
ring complex-capped
4
microtubule
4
complex-capped microtubule
4
microtubules
4
microtubule microtubules
4
microtubules composed
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!