Microtubules in Asgard archaea
- Autor(en)
- Florian Wollweber, Jingwei Xu, Rafael I Ponce-Toledo, Florina Marxer, Thiago Rodrigues-Oliveira, Anja Pössnecker, Zhen-Hao Luo, Jessie James Limlingan Malit, Anastasiia Kokhanovska, Michal Wieczorek, Christa Schleper, Martin Pilhofer
- Abstrakt
Microtubules are a hallmark of eukaryotes. Archaeal and bacterial homologs of tubulins typically form homopolymers and non-tubular superstructures. The origin of heterodimeric tubulins assembling into microtubules remains unclear. Here, we report the discovery of microtubule-forming tubulins in Asgard archaea, the closest known relatives of eukaryotes. These Asgard tubulins (AtubA/B) are closely related to eukaryotic α/β-tubulins and the enigmatic bacterial tubulins BtubA/B. Proteomics of Candidatus Lokiarchaeum ossiferum showed that AtubA/B were highly expressed. Cryoelectron microscopy structures demonstrate that AtubA/B form eukaryote-like heterodimers, which assembled into 5-protofilament bona fide microtubules in vitro. The additional paralog AtubB2 lacks a nucleotide-binding site and competitively displaced AtubB. These AtubA/B2 heterodimers polymerized into 7-protofilament non-canonical microtubules. In a sub-population of Ca. Lokiarchaeum ossiferum cells, cryo-tomography revealed tubular structures, while expansion microscopy identified AtubA/B cytoskeletal assemblies. Our findings suggest a pre-eukaryotic origin of microtubules and provide a framework for understanding the fundamental principles of microtubule assembly.
- Organisation(en)
- Department für Funktionelle und Evolutionäre Ökologie
- Externe Organisation(en)
- Eidgenössische Technische Hochschule Zürich
- Journal
- Cell
- ISSN
- 0092-8674
- DOI
- https://doi.org/10.1016/j.cell.2025.02.027
- Publikationsdatum
- 03-2025
- Peer-reviewed
- Ja
- ÖFOS 2012
- 106022 Mikrobiologie
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/b6d30842-8118-4262-bc32-56fa02ba2795