HURP facilitates spindle assembly by stabilizing microtubules and working synergistically with TPX2

Valdez, Venecia; Ma, Meisheng; Gouveia, Bernardo; Zhang, Rui; Petry, Sabine

doi:10.1101/2023.12.18.571906

Cited by 4 publications

(2 citation statements)

References 72 publications

(133 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After data collection, we applied a seam-search protocol for accurate particle alignment during processing, then generated a C1 reconstruction of the microtubule ( Fig. 5a ) 42 , 43 . The resulting 3.33 Å reconstruction ( Fig.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Mechanism of how the universal module XMAP215 γ-TuRC nucleates microtubules

McManus,

Travis,

Jeffrey

et al. 2024

Preprint

Self Cite

View full text Add to dashboard Cite

It has become increasingly evident in recent years that nucleation of microtubules from a diverse set of MTOCs requires both the γ-tubulin ring complex (γ-TuRC) and the microtubule polymerase XMAP215. Despite their essentiality, little is known about how these nucleation factors interact and work together to generate microtubules. Using biochemical domain analysis of XMAP215 and structural approaches, we find that a sixth TOG domain in XMAP215 binds γ-TuRCviaγ-tubulin as part of a broader interaction involving the C-terminal region. Moreover, TOG6 is required for XMAP215 to promote nucleation from γ-TuRC to its full extent. Interestingly, we find that XMAP215 also depends strongly on TOG5 for microtubule lattice binding and nucleation. Accordingly, we report a cryo-EM structure of TOG5 bound to the microtubule lattice that reveals promotion of lateral interactions between tubulin dimers. Finally, we find that while XMAP215 constructs’ effects on nucleation are generally proportional to their effects on polymerization, formation of a direct complex with γ-TuRC allows cooperative nucleation activity. Thus, we propose that XMAP215’s C-terminal TOGs 5 and 6 play key roles in promoting nucleation by promoting formation of longitudinal and lateral bonds in γ-TuRC templated nascent microtubules at cellular MTOCs.

show abstract

Section: Resultsmentioning

confidence: 99%

“…The microtubule data processing was done using a similar protocol as previously described 43 . Briefly, MT segments were automatically picked using ‘Filament Tracer’ in CryoSPARC 53 .…”

Section: Methodsmentioning

confidence: 99%

Mechanism of how the universal module XMAP215 γ-TuRC nucleates microtubules

McManus,

Travis,

Jeffrey

et al. 2024

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

HURP regulates Kif18A recruitment and activity to synergistically control microtubule dynamics

Perez-Bertoldi,

Zhao,

Thawani

et al. 2024

Nat Commun

View full text Add to dashboard Cite

During mitosis, microtubule dynamics are regulated to ensure proper alignment and segregation of chromosomes. The dynamics of kinetochore-attached microtubules are regulated by hepatoma-upregulated protein (HURP) and the mitotic kinesin-8 Kif18A, but the underlying mechanism remains elusive. Using single-molecule imaging in vitro, we demonstrate that Kif18A motility is regulated by HURP. While sparse decoration of HURP activates the motor, higher concentrations hinder processive motility. To shed light on this behavior, we determine the binding mode of HURP to microtubules using cryo-EM. The structure helps rationalize why HURP functions as a microtubule stabilizer. Additionally, HURP partially overlaps with the microtubule-binding site of the Kif18A motor domain, indicating that excess HURP inhibits Kif18A motility by steric exclusion. We also observe that HURP and Kif18A function together to suppress dynamics of the microtubule plus-end, providing a mechanistic basis for how they collectively serve in microtubule length control.

show abstract