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High-resolution Imaging and Analysis of Individual Astral Microtubule Dynamics in Budding Yeast
Published on: April 20, 2017
High-resolution model of the microtubule
E Nogales1, M Whittaker, R A Milligan
1Lawrence Berkeley National Laboratory, Molecular and Cell Biology Department, University of California at Berkeley, California 94720, USA. enogales@lbl.gov
Cell
|February 16, 1999
Summary
This study reveals the high-resolution structure of microtubules, detailing tubulin conformation and orientation. Key findings include exposed nucleotide sites and interactions influencing microtubule dynamics and drug binding.
Area of Science:
- Cell Biology
- Structural Biology
- Biochemistry
Background:
- Microtubules are essential cytoskeletal polymers involved in diverse cellular processes.
- Understanding microtubule structure at high resolution is crucial for deciphering their function and interactions.
Purpose of the Study:
- To generate a high-resolution structural model of the microtubule.
- To define the precise orientation and conformation of tubulin within the microtubule polymer.
Main Methods:
- Docking the crystal structure of tubulin into a 20 Angstrom resolution electron microscopy map of the microtubule.
- Analyzing the resulting model to identify structural features and interfaces.
Main Results:
- A high-resolution model of the microtubule was successfully obtained, showing excellent agreement with the experimental map.
- Tubulin conformation in the microtubule is similar to that in isolated tubulin polymers.
- Specific structural elements, including C-terminal helices and loops, were localized to the microtubule surface and lumen.
- The nucleotide-binding site in beta-tubulin and a catalytic residue in alpha-tubulin are exposed at opposite microtubule ends.
- Detailed descriptions of longitudinal and lateral inter-monomer interfaces were provided, including nucleotide-sensitive interactions relevant to taxol binding.
Conclusions:
- The study provides a detailed structural framework for understanding microtubule assembly and dynamics.
- The findings elucidate the structural basis for nucleotide exposure and potential regulatory mechanisms at microtubule ends.
- The identified structural features offer insights into drug interactions, such as taxol binding, within the microtubule lattice.
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