| 2003 |
KNL-1 (C. elegans ortholog) is required downstream of CeCENP-A and CeCENP-C in a linear kinetochore assembly hierarchy, forms a near-stoichiometric complex with CeNDC-80 and HIM-10, and is required to target multiple outer kinetochore components including the Ndc80 complex to build the microtubule-binding interface. |
RNAi-based genomics, co-immunoprecipitation from embryonic extracts, epistasis analysis |
Genes & development |
High |
14522947
|
| 2007 |
Human KNL1 (Blinkin/AF15q14) directly interacts via its N-terminal and middle domains with the TPR domains of Bub1 and BubR1, recruiting them to kinetochores; its C-terminal domain associates with the hMis12 complex. KNL1 knockdown causes checkpoint failure and chromosome misalignment phenocopying Bub1+BubR1 double knockdown. |
RNAi, direct binding assays, co-immunoprecipitation, live-cell imaging |
Developmental cell |
High |
17981135
|
| 2007 |
Vertebrate KNL1 and CENP-K coordinately direct localization of the Ndc80 complex to kinetochores; simultaneous depletion of both abolishes all kinetochore assembly downstream of centromeric chromatin, revealing functional redundancy not present in C. elegans. |
RNAi depletion, immunofluorescence, epistasis analysis in chicken DT40 cells |
Molecular biology of the cell |
High |
18045986
|
| 2010 |
A conserved RVSF motif in KNL1 directly recruits protein phosphatase 1 (PP1) to the outer kinetochore to dephosphorylate Aurora B substrates and stabilize microtubule attachments; Aurora B phosphorylation of KNL1 disrupts the KNL1-PP1 interaction, creating a positive feedback mechanism that prevents PP1 recruitment where Aurora B is active. |
Co-immunoprecipitation, in vitro binding assays, phospho-mutant analysis, live-cell imaging, kinetochore PP1 quantification |
The Journal of cell biology |
High |
20231380
|
| 2011 |
The RVSF motif of yeast Spc105 (KNL1 ortholog) binds PP1/Glc7 and this interaction is essential for viability by silencing the spindle assembly checkpoint; PP1 amount at the kinetochore must be finely tuned as either loss or gain of one extra PP1 copy is detrimental. |
Exact gene replacement in budding yeast, genetic epistasis, quantitative imaging |
Current biology : CB |
High |
21640906
|
| 2012 |
Fission yeast Mph1 (MPS1 ortholog) phosphorylates MELT repeat sequences of Spc7 (KNL1/Blinkin ortholog), and this phosphorylation directly promotes binding of the Bub1-Bub3 complex to kinetochores, which is required for SAC activation (Mad1-Mad2-Mad3 localization) and chromosome alignment. Non-phosphorylatable spc7-12A abolishes Bub1-Bub3 kinetochore targeting; phosphomimetic spc7-12E forces constitutive localization. |
In vitro kinase assay, in vitro binding assay, phosphomutant genetics, live-cell imaging in fission yeast |
Nature cell biology |
High |
22660415
|
| 2012 |
Mph1 (Mps1) phosphorylation of conserved MELT motifs in S. pombe Spc7 recruits Bub1 and Bub3 to the kinetochore, and this phospho-dependent recruitment is required to maintain the SAC signal. |
Phospho-mutant genetics, mass spectrometry, in vitro binding, kinetochore localization assays |
Current biology : CB |
High |
22521786
|
| 2012 |
The N-terminal domain of KNL-1 contains microtubule-binding and -bundling activity; this activity is dispensable for load-bearing attachment and checkpoint activation but contributes independently to checkpoint silencing at the kinetochore, additively with PP1 docking. |
In vitro microtubule-binding assay, selective point mutagenesis, C. elegans embryo imaging, checkpoint silencing assays |
The Journal of cell biology |
High |
22331849
|
| 2012 |
Crystal structure of the Bub1 TPR domain in complex with the KI motif of Knl1 was determined; point mutations on the convex TPR surface impaired the Bub1-Knl1 interaction in vitro and in vivo. A 62-residue segment of Bub1 C-terminal to the TPRs (containing the Bub3-binding domain) was found necessary and sufficient for kinetochore recruitment of Bub1. |
X-ray crystallography, in vitro binding assays, site-directed mutagenesis, cell-based localization |
The Journal of cell biology |
High |
22331848
|
| 2013 |
KNL1 contains an array of MELT repeats that serve as individual Mps1-phosphorylated docking sites for Bub3 (and thereby Bub1/BubR1); a minimum of four active MELT repeats is sufficient to support chromosome congression and SAC function. PP1 binding to KNL1 during prometaphase reduces Bub protein levels at kinetochores to the equivalent of four active MELT repeats. |
MELT repeat deletion constructs, rescue assays in KNL1-depleted cells, quantitative immunofluorescence |
Journal of cell science |
High |
24363448
|
| 2013 |
KNL1 contains an extensive array of short linear BUB recruitment modules (TxxΩ and MELT motifs) that can independently localize BUB1; increasing numbers of modules progressively enhance chromosome biorientation efficiency, while a minimal array suffices for robust checkpoint. A minimal set of artificially designed identical modules maintains normal KNL1 function. |
Engineered KNL1 variants with defined module numbers, BUB1 quantification at kinetochores, chromosome segregation assays |
The Journal of cell biology |
High |
24344183
|
| 2013 |
KNL1 N-terminus is essential for Aurora B kinase activity at kinetochores; KNL1 promotes Aurora B activity partly through supporting Bub1 kinase activity, and partly through an additional Bub1-independent pathway. Ectopic targeting of Aurora B does not fully rescue Aurora B activity upon KNL1 depletion. |
RNAi depletion, phospho-substrate immunofluorescence, ectopic targeting constructs, live-cell imaging |
The Journal of cell biology |
High |
24344188
|
| 2013 |
KI motifs in the N-terminal region of human Knl1 cooperate with the adjacent MELT motif to assemble comprehensive SAC signaling complexes; Knl1(1-250) containing both KI motifs and one MELT motif can fully restore SAC and chromosome alignment in Knl1-depleted cells. KI motifs function as enhancers of MELT function. |
Knl1 truncation/rescue constructs, co-immunoprecipitation, kinetochore localization assays, SAC functional assays |
Current biology : CB |
High |
24361068
|
| 2014 |
BubR1-associated PP2A-B56 dephosphorylates Mps1-phosphorylated MELT motifs on Knl1 in vitro and in vivo, thereby removing the docking sites for Bub1/BubR1 and promoting SAC silencing via a negative feedback loop. |
In vitro phosphatase assay, cell-based rescue/depletion, quantitative kinetochore protein measurements |
The Journal of cell biology |
High |
25246613
|
| 2014 |
C. elegans KNL-1 exists as a decameric oligomer mediated by a small hydrophobic N-terminal domain; however, precise disruption of this oligomerization does not alter KNL-1 localization or embryonic viability in gene replacement experiments. |
Biochemical oligomerization assays, electron microscopy, site-directed mutagenesis, C. elegans gene replacement |
Molecular biology of the cell |
Medium |
25411336
|
| 2015 |
Human KNL1 MELT repeats contain a vertebrate-specific SHT motif C-terminal to the MELT sequence; MPS1 phosphorylates SHT in a manner requiring prior MELT phosphorylation (sequential multisite phosphorylation), and phospho-SHT synergizes with phospho-MELT to promote BUB3/BUB1 binding in vitro and at kinetochores. BUB3 mutated in its predicted SHpT-binding surface cannot localize to kinetochores. |
Systematic in vitro binding screens, phosphomutant analysis, cell-based localization assays |
Molecular cell |
High |
25661489
|
| 2015 |
The KNL1-Bub3-Bub1 (KBB) pathway is required for SAC activation at misaligned (tensionless) kinetochores during normal mitosis but is not required when kinetochores are fully unattached; the RZZ complex provides a separate, KBB-independent pathway for Mad1-Mad2 recruitment to unattached kinetochores. |
CRISPR/gene editing, RNAi, Mad2 kinetochore localization assays, checkpoint response assays in diploid human cells |
Developmental cell |
High |
26651294
|
| 2015 |
The RZZ complex localizes to the N-terminus of KNL1 downstream of Bub1 to mediate robust Mad1-Mad2 kinetochore localization in human cells, establishing KNL1 as a platform for RZZ-dependent Mad1-Mad2 recruitment. |
RNAi, truncation constructs, kinetochore localization assays, co-immunoprecipitation |
Open biology |
Medium |
26581576
|
| 2016 |
In fission yeast, multisite binding of Bub3 to the Spc7 (KNL1) MELT array is required for Mph1 (Mps1)-dependent interaction of Bub1 with Mad1-Mad2, thereby toggling the spindle checkpoint switch; Bub3-Spc7 binding licenses the Bub1-Mad1-Mad2 interaction. |
Genetic epistasis in S. pombe, co-immunoprecipitation, phosphomutant analysis, checkpoint functional assays |
Current biology : CB |
High |
27618268
|
| 2018 |
Crystal structure and NMR analysis show that KNL1 binds PP1 via its RVSF motif and binds microtubules via overlapping binding sites, demonstrating that microtubule and PP1 binding to KNL1 are mutually exclusive; Aurora B phosphorylation of KNL1 causes distinct disruption patterns for each complex, and co-sedimentation assays confirm preferential formation of KNL1:PP1 holoenzyme in the presence of PP1. |
X-ray crystallography, NMR spectroscopy, in vitro binding/competition assays, co-sedimentation assays |
Structure |
High |
30100357
|
| 2018 |
RZZ's sole role in SAC activation is to tether Mad1-Mad2 to kinetochores; Bub1 and KNL1 (via MPS1-dependent phosphorylation) activate kinetochore-bound Mad1-Mad2 to produce the 'wait anaphase' signal but are not required for fibrous corona formation. MPS1 kinase triggers fibrous corona formation by phosphorylating N-terminal sites on Rod, not KNL1. |
Genome editing (KO of Bub1, KNL1, RZZ subunits), kinetochore protein localization assays, checkpoint functional assays |
Current biology : CB |
High |
30415700
|
| 2019 |
Conditional KNL1 deletion from embryonic mouse brain causes chromosome missegregation in neural progenitor cells, leading to DNA damage on missegregated chromosomes, p53 activation, apoptosis, and microcephaly; without both KNL1 and p53-dependent safeguards, genome-damaged cells persist causing lethality. |
Conditional Cre-lox knockout in mouse brain, mitotic index analysis, immunofluorescence, p53 double-KO epistasis |
Nature communications |
High |
31197172
|
| 2024 |
In C. elegans postmitotic neurons, KNL-1 (with KMN network partners) controls dendrite branching by modulating F-actin dynamics; KNL-1 loss causes excess dendritic branching, altered actin and microtubule dynamics, and the N-terminus of KNL-1 can initiate F-actin assembly. |
C. elegans genetics, live imaging, actin dynamics assays, neuronal morphology quantification, gene replacement constructs |
The Journal of cell biology |
Medium |
39625434
|
| 2024 |
In C. elegans, postmitotic KNL-1 is required for proper axonal organization; its PP1-recruiting SILK/RVSF motifs and SAC-activating signaling motifs (not just microtubule-binding activity) are required for neurodevelopmental function, while NDC-80 microtubule binding facilitates axon-axon contacts during nerve ring formation. |
C. elegans gene-replacement, fluorescent imaging, signaling motif mutagenesis, axon organization quantification |
Molecular biology of the cell |
Medium |
38656792
|