Structural transitions in the GTP cap visualized by cryo-electron microscopy of catalytically inactive microtubules
Abstract
Microtubules (MTs) are nonequilibrium polymers that switch between states of growth and shrinkage. This property is critical for their function and is a consequence of GTP hydrolysis in the MT. The structure of the stable GTP part of the MT (the GTP cap) has previously been inferred from MTs polymerized with nonhydrolyzable GTP analogs. Here, we report high-resolution structures of MTs truly containing GTP, polymerized from mutated, hydrolysis-deficient tubulins. We find that GTP-MTs have an “expanded lattice” and a “closed seam,” structural characteristics possibly responsible for stabilizing the GTP cap. These results provide insight into the structural transitions at growing MT ends, furthering our understanding of the bistable nature of MTs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 07, 2022
- Source ID
- 10.1073/pnas.2114994119
Entities
People
- Basil J. Greber
- Benjamin LaFrance
- Chloe O. McCollum
- Davide Normanno
- Eva Nogales
- Gil Henkin
- Johanna Roostalu
- Rui Zhang
- Thomas Surrey
Organizations
- Barcelona Institute for Science and Technology
- California Institute for Quantitative Biosciences
- Cancer Research UK
- Catalan Institution for Research and Advanced Studies
- European Research Council
- Francis Crick Institute
- Howard Hughes Medical Institute
- Lawrence Berkeley National Laboratory
- Medical Research Council
- National Institute of General Medical Sciences
- Wellcome