GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com


Jump to: navigation, search

Espeut, J, Cheerambathur, DK, Krenning, L, Oegema, K and Desai, A (2012) Microtubule binding by KNL-1 contributes to spindle checkpoint silencing at the kinetochore. J. Cell Biol. 196:469-82


Accurate chromosome segregation requires coordination between microtubule attachment and spindle checkpoint signaling at the kinetochore. The kinetochore-localized KMN (KNL-1/Mis12 complex/Ndc80 complex) network, which mediates microtubule attachment and scaffolds checkpoint signaling, harbors two distinct microtubule-binding activities: the load-bearing activity of the Ndc80 complex and a less well-understood activity in KNL-1. In this paper, we show that KNL-1 microtubule-binding and -bundling activity resides in its extreme N terminus. Selective perturbation of KNL-1 microtubule binding in Caenorhabditis elegans embryos revealed that this activity is dispensable for both load-bearing attachment formation and checkpoint activation but plays a role in checkpoint silencing at the kinetochore. Perturbation of both microtubule binding and protein phosphatase 1 docking at the KNL-1 N terminus additively affected checkpoint silencing, indicating that, despite their proximity in KNL-1, these two activities make independent contributions. We propose that microtubule binding by KNL-1 functions in checkpoint silencing by sensing microtubules attached to kinetochores and relaying their presence to eliminate generation of the checkpoint signal.


PubMed PMC3284002 Online version:10.1083/jcb.201111107


Amino Acid Sequence; Animals; Blotting, Western; Caenorhabditis elegans/genetics; Caenorhabditis elegans/metabolism; Caenorhabditis elegans Proteins/genetics; Caenorhabditis elegans Proteins/metabolism; Cell Cycle Checkpoints; Chromosome Segregation; Embryo, Nonmammalian/cytology; Embryo, Nonmammalian/metabolism; Green Fluorescent Proteins/genetics; Green Fluorescent Proteins/metabolism; Immunoprecipitation; Kinetochores/physiology; Microtubule-Associated Proteins/genetics; Microtubule-Associated Proteins/metabolism; Microtubules/metabolism; Mitotic Spindle Apparatus/physiology; Molecular Sequence Data; Sequence Homology, Amino Acid



Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status


GO:0051382: kinetochore assembly



Knl-1 is vital for signaling and attachment of microtubules to the KMN network as seen in video 1.

CACAO 3781

See also


See Help:References for how to manage references in GONUTS.