Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Reconstitution of the augmin complex provides insights into its architecture and function.
Hsia KC
,
Wilson-Kubalek EM
,
Dottore A
,
Hao Q
,
Tsai KL
,
Forth S
,
Shimamoto Y
,
Milligan RA
,
Kapoor TM
.
???displayArticle.abstract???
Proper microtubule nucleation during cell division requires augmin, a microtubule-associated hetero-octameric protein complex. In current models, augmin recruits γ-tubulin, through the carboxyl terminus of its hDgt6 subunit to nucleate microtubules within spindles. However, augmin's biochemical complexity has restricted analysis of its structural organization and function. Here, we reconstitute human augmin and show that it is a Y-shaped complex that can adopt multiple conformations. Further, we find that a dimeric sub-complex retains in vitro microtubule-binding properties of octameric complexes, but not proper metaphase spindle localization. Addition of octameric augmin complexes to Xenopus egg extracts promotes microtubule aster formation, an activity enhanced by Ran-GTP. This activity requires microtubule binding, but not the characterized hDgt6 γ-tubulin-recruitment domain. Tetrameric sub-complexes induce asters, but activity and microtubule bundling within asters are reduced compared with octameric complexes. Together, our findings shed light on augmin's structural organization and microtubule-binding properties, and define subunits required for its function in organizing microtubule-based structures.
Bettencourt-Dias,
Centrosome biogenesis and function: centrosomics brings new understanding.
2007, Pubmed
Bettencourt-Dias,
Centrosome biogenesis and function: centrosomics brings new understanding.
2007,
Pubmed
Colombié,
Meiosis-specific stable binding of augmin to acentrosomal spindle poles promotes biased microtubule assembly in oocytes.
2013,
Pubmed
Desai,
The use of Xenopus egg extracts to study mitotic spindle assembly and function in vitro.
1999,
Pubmed
,
Xenbase
Dumont,
Acentrosomal spindle assembly and chromosome segregation during oocyte meiosis.
2012,
Pubmed
Folta-Stogniew,
Determination of molecular masses of proteins in solution: Implementation of an HPLC size exclusion chromatography and laser light scattering service in a core laboratory.
1999,
Pubmed
Goshima,
Augmin: a protein complex required for centrosome-independent microtubule generation within the spindle.
2008,
Pubmed
Hayward,
Synergy between multiple microtubule-generating pathways confers robustness to centrosome-driven mitotic spindle formation.
2014,
Pubmed
Hohn,
SPARX, a new environment for Cryo-EM image processing.
2007,
Pubmed
Kamasaki,
Augmin-dependent microtubule nucleation at microtubule walls in the spindle.
2013,
Pubmed
Karsenti,
The mitotic spindle: a self-made machine.
2001,
Pubmed
,
Xenbase
Kelly,
Correcting aberrant kinetochore microtubule attachments: an Aurora B-centric view.
2009,
Pubmed
Kollman,
Microtubule nucleation by γ-tubulin complexes.
2011,
Pubmed
Lawo,
HAUS, the 8-subunit human Augmin complex, regulates centrosome and spindle integrity.
2009,
Pubmed
Lüders,
Microtubule-organizing centres: a re-evaluation.
2007,
Pubmed
Meunier,
Microtubule assembly during mitosis - from distinct origins to distinct functions?
2012,
Pubmed
Petry,
Augmin promotes meiotic spindle formation and bipolarity in Xenopus egg extracts.
2011,
Pubmed
,
Xenbase
Petry,
Branching microtubule nucleation in Xenopus egg extracts mediated by augmin and TPX2.
2013,
Pubmed
,
Xenbase
Smith,
Interactive, computer-assisted tracking of speckle trajectories in fluorescence microscopy: application to actin polymerization and membrane fusion.
2011,
Pubmed
Subramanian,
Insights into antiparallel microtubule crosslinking by PRC1, a conserved nonmotor microtubule binding protein.
2010,
Pubmed
Suloway,
Automated molecular microscopy: the new Leginon system.
2005,
Pubmed
Tan,
The pST44 polycistronic expression system for producing protein complexes in Escherichia coli.
2005,
Pubmed
Tang,
EMAN2: an extensible image processing suite for electron microscopy.
2007,
Pubmed
Teixidó-Travesa,
The where, when and how of microtubule nucleation - one ring to rule them all.
2012,
Pubmed
Trowitzsch,
New baculovirus expression tools for recombinant protein complex production.
2010,
Pubmed
Uehara,
The augmin complex plays a critical role in spindle microtubule generation for mitotic progression and cytokinesis in human cells.
2009,
Pubmed
Wadsworth,
E pluribus unum: towards a universal mechanism for spindle assembly.
2004,
Pubmed
Walczak,
Mechanisms of chromosome behaviour during mitosis.
2010,
Pubmed
Walczak,
Mechanisms of mitotic spindle assembly and function.
2008,
Pubmed
,
Xenbase
Wu,
Hice1, a novel microtubule-associated protein required for maintenance of spindle integrity and chromosomal stability in human cells.
2008,
Pubmed
Yang,
Iterative stable alignment and clustering of 2D transmission electron microscope images.
2012,
Pubmed