Integrated model of the vertebrate augmin complex
Year: 2023
Type: article
Abstract: ABSTRACT Accurate segregation of chromosomes is required to maintain genome integrity during cell division. This feat is accomplished by the microtubule-based spindle. To build a spindle rapidly and with high fidelity, cells take advantage of branching microtubule nucleation, which exponentially amplifies microtubules during cell division. Branching microtubule nucleation relies on the hetero-octameric augmin complex, but understanding how augmin promotes branching has been hindered by a lack of structural information about the complex. Here, we report an integrated model of vertebrate augmin, combining cryo-electron microscopy, advanced protein structural prediction, and the visualization of fused bulky tags via negative stain electron microscopy. This strategy allowed us to identify the location and orientation of each subunit within the structure. Evolutionary analysis of augmin’s structure reveals that it is highly conserved across diverse eukaryotes, and that augmin contains a previously-unidentified microtubule binding site. Moreover, we identify homology with the kinetochore-localized NDC80 complex. This new model of the augmin complex provides insight towards the mechanism and evolution of branching microtubule nucleation.
Source: Nature Communications
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $6,290
Funders: National Science Foundation, U.S. Department of Health and Human Services, Helen Hay Whitney Foundation, Case Western Reserve University, Princeton Center for Complex Materials, National Institutes of Health, University of California, San Francisco, Materials Research Science and Engineering Center, Harvard University, Center for Cellular Imaging, Washington University, National Institute of General Medical Sciences, Division of Materials Research
Awards: G1052925518, G1644031019, G1746067696, G1796337455, G1907146399, G2174132073, G2433208693, G2497455034, G3372464033, Resource for Biocomputing Visualization and Informatics, G340396948, G3603580073, G3835604489, G3923339477, G4176199854, G4617261419, G4815039349, G5528850602, Role and Mechanisms of Microtubule Nucleation in Spindle Assembly, G6536552022, Princeton Center for Complex Materials, G7361609772, Structure-based mechanism of the augmin complex in promoting branching microtubule nucleation and spindle assembly, Structural and functional studies of axonemal microtubule inner proteins (MIPs), G9000001160, G9000061601, G9000086851, G9000131913, G9000261022
OpenAlex ID: W4365447709