|
1
|
Doran MH, Niu Q, Zeng J, Beneke T, Smith J, Ren P, Fochler S, Coscia A, Höög JL, Meleppattu S, Lishko PV, Wheeler RJ, Gluenz E, Zhang R, Brown A. Evolutionary adaptations of doublet microtubules in trypanosomatid parasites. Science 2025; 387:eadr5507. [PMID: 40080577 DOI: 10.1126/science.adr5507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2024] [Revised: 11/04/2024] [Accepted: 12/20/2024] [Indexed: 03/15/2025]
Abstract
The movement and pathogenicity of trypanosomatid species, the causative agents of trypanosomiasis and leishmaniasis, are dependent on a flagellum that contains an axoneme of dynein-bound doublet microtubules (DMTs). In this work, we present cryo-electron microscopy structures of DMTs from two trypanosomatid species, Leishmania tarentolae and Crithidia fasciculata, at resolutions up to 2.7 angstrom. The structures revealed 27 trypanosomatid-specific microtubule inner proteins, a specialized dynein-docking complex, and the presence of paralogous proteins that enable higher-order periodicities or proximal-distal patterning. Leveraging the genetic tractability of trypanosomatid species, we quantified the location and contribution of each structure-identified protein to swimming behavior. Our study shows that proper B-tubule closure is critical for flagellar motility, exemplifying how integrating structural identification with systematic gene deletion can dissect individual protein contributions to flagellar motility.
Collapse
Affiliation(s)
- Matthew H Doran
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Qingwei Niu
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
- Molecular Cell Biology (MCB) graduate program, Division of Biology and Biomedical Sciences, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
- Department of Cell Biology and Physiology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Jianwei Zeng
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Tom Beneke
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - James Smith
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Peter Ren
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Sophia Fochler
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Adrian Coscia
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Johanna L Höög
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Shimi Meleppattu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Polina V Lishko
- Department of Cell Biology and Physiology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Richard J Wheeler
- Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, Edinburgh, UK
| | - Eva Gluenz
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Rui Zhang
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Alan Brown
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
|
2
|
Walton T, Doran MH, Brown A. Structural determination and modeling of ciliary microtubules. Acta Crystallogr D Struct Biol 2024; 80:220-231. [PMID: 38451206 PMCID: PMC10994176 DOI: 10.1107/s2059798324001815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 02/24/2024] [Indexed: 03/08/2024] Open
Abstract
The axoneme, a microtubule-based array at the center of every cilium, has been the subject of structural investigations for decades, but only recent advances in cryo-EM and cryo-ET have allowed a molecular-level interpretation of the entire complex to be achieved. The unique properties of the nine doublet microtubules and central pair of singlet microtubules that form the axoneme, including the highly decorated tubulin lattice and the docking of massive axonemal complexes, provide opportunities and challenges for sample preparation, 3D reconstruction and atomic modeling. Here, the approaches used for cryo-EM and cryo-ET of axonemes are reviewed, while highlighting the unique opportunities provided by the latest generation of AI-guided tools that are transforming structural biology.
Collapse
Affiliation(s)
- Travis Walton
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Matthew H. Doran
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Alan Brown
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|