Dephosphorylation of the Ndc80 Tail Stabilizes Kinetochore-Microtubule Attachments via the Ska Complex

Cheerambathur, Dhanya K.; Prevo, Bram; Hattersley, Neil; Lewellyn, Lindsay; Corbett, K.D.; Oegema, Karen; Desai, Arshad

doi:10.1016/j.devcel.2017.04.013

Cited by 63 publications

(109 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, although the Ska1 MTBD is necessary and sufficient for Ska1 complex microtubule binding and spindle localization [2], we note that recent work has also suggested a contribution to microtubule interactions from Ska3 [28]. Ultimately, these activities must be regulated [13, 29, 30] and integrated with other players at the kinetochore, including the Ndc80 complex [2, 31, 32], to ensure faithful chromosome segregation during every cell division.…”

Section: Resultsmentioning

confidence: 99%

Microtubule Tip Tracking by the Spindle and Kinetochore Protein Ska1 Requires Diverse Tubulin-Interacting Surfaces

et al. 2017

View full text Add to dashboard Cite

Summary The macromolecular kinetochore functions to generate interactions between chromosomal DNA and spindle microtubules [1]. To facilitate chromosome movement and segregation, kinetochores must maintain associations with both growing and shrinking microtubule ends. It is critical to define the proteins and their properties that allow kinetochores to associate with dynamic microtubules. The kinetochore-localized human Ska1 complex binds to microtubules and tracks with depolymerizing microtubule ends [2]. We now demonstrate that the Ska1 complex also autonomously tracks with growing microtubule ends in vitro, a key property that would allow this complex to act at kinetochores to mediate persistent associations with dynamic microtubules. To define the basis for Ska1 complex interactions with dynamic microtubules, we investigated the tubulin-binding properties of the Ska1 microtubule binding domain. In addition to binding to the microtubule lattice and dolastatin-induced protofilament-like structures, we demonstrate that the Ska1 microtubule binding domain can associate with soluble tubulin heterodimers and promote assembly of oligomeric ring-like tubulin structures. We generated mutations on distinct surfaces of the Ska1 microtubule binding domain that disrupt binding to soluble tubulin, but do not prevent microtubule binding. These mutants display compromised microtubule tracking activity in vitro and result in defective chromosome alignment and mitotic progression in cells using a CRISPR/Cas9-based replacement assay. Our work supports a model in which multiple surfaces of Ska1 interact with diverse tubulin substrates to associate with dynamic microtubule polymers and facilitate optimal chromosome segregation.

show abstract

Section: Resultsmentioning

confidence: 99%

Microtubule Tip Tracking by the Spindle and Kinetochore Protein Ska1 Requires Diverse Tubulin-Interacting Surfaces

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Therefore, it is still unclear how the Ska and Ndc80 complexes interact with one another at the atomic level and how these two complexes are organized in three dimensions. In spite of these findings, Ska kinetochore recruitment seems more complicated because of two recent studies suggesting that the Ndc80 N‐terminus also plays a role in recruiting Ska to kinetochores . Janczyk et al .…”

Section: How Is Ska Targeted To Kinetochores?mentioning

confidence: 99%

Multitasking Ska in Chromosome Segregation: Its Distinct Pools Might Specify Various Functions

2018

View full text Add to dashboard Cite

The human spindle and kinetochore associated (Ska) complex is required for proper mitotic progression. Extensive studies have demonstrated its important functions in both stable kinetochore-microtubule interactions and spindle checkpoint silencing. We suggest a model to explain how various Ska functions might be fulfilled by distinct pools of Ska at kinetochores. The Ndc80-loop pool of Ska is recruited by the Ndc80 loop, or together with some of its flanking sequences, and the recruitment is also dependent on Cdk1-mediated Ska3 phosphorylation. This pool seems to play a more important role in silencing the spindle checkpoint than stabilizing kinetochore-microtubule interactions. In contrast, the Ndc80-N-terminus pool of Ska is recruited by the N-terminal domains of Ndc80 and appears to be more important for stabilizing kinetochore-microtubule interactions. Here, we review and discuss the evidence that supports this model and suggest further experiments to test the functioning mechanisms of the Ska complex.

show abstract

“…In some cases, relevant domains have been identified and structurally characterized in other species; in these cases, existing structural and biochemical information and primary sequence alignments can be employed to generate mechanistically informative mutations (e.g. Cheerambathur et al 2013; Cheerambathur et al 2017). If no orthologues can be identified, or there is little insight into functional domains, one can analyze secondary and 3D structure prediction; for this purpose there are online prediction programs such as Phyre2 (http://www.sbg.bio.ic.ac.uk/~phyre2/html/page.cgi?id=index) and Jpred (http://www.compbio.dundee.ac.uk/jpred/).…”

Section: Engineering Cell Division Genesmentioning

confidence: 99%

“…chromosome condensation (Maddox et al 2006), chromosome alignment (Cheerambathur et al 2017) (Fig. 7), cortical dynamics (Maddox et al 2007; Carvalho et al 2009; Lewellyn et al 2011), etc.…”

Section: Monitoring Of Cell Division Processesmentioning

confidence: 99%

See 1 more Smart Citation

Employing the one-cell C. elegans embryo to study cell division processes

Hattersley

Lara-González

Cheerambathur

et al. 2018

Methods in Cell Biology

Self Cite

View full text Add to dashboard Cite

The one-cell Caenorhabditis elegans embryo offers many advantages for mechanistic analysis of cell division processes. Conservation of key genes and pathways involved in cell division makes findings in C. elegans broadly relevant. A key technical advantage of this system is the ability to penetrantly deplete essential gene products by RNA interference (RNAi) and replace them with wild-type or mutant versions expressed at endogenous levels from single copy RNAi-resistant transgene insertions. This ability to precisely perturb essential genes is complemented by the inherently highly reproducible nature of the zygotic division that facilitates development of quantitative imaging assays. Here, we detail approaches to generate targeted single copy transgene insertions that are RNAi-resistant, to engineer variants of individual genes employing transgene insertions as well as at the endogenous locus, and to in situ tag genes with fluorophores/purification tags. We also describe imaging assays and common image analysis tools employed to quantitatively monitor phenotypic effects of specific perturbations on meiotic and mitotic chromosome segregation, centrosome assembly/function, and cortical dynamics/cytokinesis.

show abstract

Dephosphorylation of the Ndc80 Tail Stabilizes Kinetochore-Microtubule Attachments via the Ska Complex

Cited by 63 publications

References 54 publications

Microtubule Tip Tracking by the Spindle and Kinetochore Protein Ska1 Requires Diverse Tubulin-Interacting Surfaces

Microtubule Tip Tracking by the Spindle and Kinetochore Protein Ska1 Requires Diverse Tubulin-Interacting Surfaces

Multitasking Ska in Chromosome Segregation: Its Distinct Pools Might Specify Various Functions

Employing the one-cell C. elegans embryo to study cell division processes

Contact Info

Product

Resources

About