| 2006 |
Bora is required for the activation of Aurora-A at the onset of mitosis; both Drosophila and human Bora bind to Aurora-A and activate the kinase in vitro. In interphase cells Bora is nuclear, but upon mitotic entry it is excluded from the nucleus and translocates to the cytoplasm in a Cdc2-dependent manner, where it can bind and activate Aurora-A. |
Genetic loss-of-function in Drosophila PNS (bora mutants phenocopy aurora-A), in vitro kinase assay, rescue by Bora overexpression, live-cell fractionation/imaging for localization |
Developmental Cell |
High |
16890155
|
| 2008 |
Bora accumulates in G2, interacts with Plk1, and controls the accessibility of Plk1's activation loop for phosphorylation (T210) and activation by Aurora A, thereby promoting Cdk1 activation and mitotic entry. Bora and Aurora A act synergistically to activate Plk1. |
Co-immunoprecipitation of Bora with Plk1, RNAi knockdown, in vitro kinase assay reconstitution, cell cycle staging by FACS |
Science |
High |
18566290
|
| 2008 |
Plk1 phosphorylates a conserved DSGxxT degron in Bora, promoting its recognition by the SCF-β-TrCP E3 ubiquitin ligase and proteasomal degradation in mitosis. Bora protein peaks in G2 and is degraded during mitosis; a non-degradable Bora variant prolongs metaphase and delays anaphase onset. |
Co-IP of Bora with β-TrCP, in vitro phosphorylation assay, site-directed mutagenesis of degron, proteasome inhibition, cell cycle synchronization |
Journal of Cell Biology |
High |
18378770
|
| 2010 |
In C. elegans, SPAT-1 (Bora ortholog) acts with PLK-1 (not AIR-1/Aurora A) to regulate both PAR polarity and cell cycle progression; SPAT-1 binds PLK-1 directly, and depletion of SPAT-1 or PLK-1 produces identical polarity and division defects distinct from those of air-1 depletion. |
RNAi depletion, Co-IP of SPAT-1 with PLK-1, genetic epistasis (par-2 suppressor rescue), live imaging |
Development |
High |
20823068
|
| 2013 |
The Bora-Aurora A complex remains the major activator of Plk1 in mitosis; a fraction of Bora is retained in mitosis and is essential for continued Aurora A-dependent T210 phosphorylation of Plk1, functioning as a bistable switch. |
FRET-based Plk1 activity biosensor, immunoprecipitation, quantitative phospho-immunoblot, Aurora A inhibitor titration |
Journal of Cell Science |
High |
24338364
|
| 2013 |
ATR phosphorylates Bora at Thr-501 following UV irradiation; phospho-Thr-501 is recognized by SCF-β-TrCP, targeting Bora for ubiquitin-mediated degradation, which compromises Plk1 activation and contributes to DNA-damage-induced G2 arrest. |
In vitro kinase assay with ATR, Co-IP of Bora with β-TrCP, phospho-specific antibody, site-directed mutagenesis, G2 arrest assay |
Journal of Biological Chemistry |
High |
23592782
|
| 2013 |
Phosphorylation of Bora at Ser274 and Ser278 is required for Pin1 binding; Pin1 interaction alters Bora's cytoplasmic translocation and promotes premature β-TrCP-mediated degradation, delaying mitotic entry. Aurora A phosphorylates Pin1 at Ser16 to suppress this negative regulation. |
Co-IP of Bora with Pin1 and Aurora A, site-directed mutagenesis of Bora phosphosites, live-cell imaging of Bora translocation, cell cycle FACS |
Journal of Cell Science |
Medium |
23970419
|
| 2014 |
Cdk1-mediated phosphorylation of Bora on the consensus site T52 blocks Plk1-mediated Bora degradation in CSF extracts; upon fertilization, Calcineurin dephosphorylates T52, triggering Plx1 activity oscillations, demonstrating that Cdk1 regulates Bora stability through an incoherent feedforward loop. |
Xenopus CSF extract biochemistry, phospho-specific immunoblot, calcineurin inhibition, site-directed mutagenesis, GFP-Bora degradation assay |
Cell Cycle |
Medium |
24675888
|
| 2015 |
CDK-1 phosphorylates SPAT-1/Bora at multiple sites to regulate its interaction with PLK-1/Plk1 and trigger mitotic entry in C. elegans embryos; phospho-SPAT-1 promotes Aurora A-mediated PLK-1 T-loop phosphorylation in vitro. This mechanism is conserved: phosphorylation of human Bora by Cdk1 also promotes Aurora A-dependent Plk1 phosphorylation. |
In vitro kinase assay (CDK-1 on SPAT-1, Aurora A on PLK-1), site-directed mutagenesis of CDK-1 phosphosites in SPAT-1/Bora, C. elegans embryo live imaging, co-IP of SPAT-1 with PLK-1 |
Journal of Cell Biology |
High |
25753036
|
| 2016 |
Bora interacts with Cyclin B and is phosphorylated by Cyclin B/Cdk1 at three conserved N-terminal Sp/Tp residues; the N-terminus of Bora (first 225 aa) containing two Cyclin binding motifs is sufficient to promote Aurora A-mediated Plk1 phosphorylation in vitro. Mutation of either Cyclin binding sites or the three phosphorylation sites abrogates Plk1 activation and impairs mitotic entry after DNA damage. |
In vitro kinase assay, GST pulldown of Bora with Cyclin B, site-directed mutagenesis, FRET Plk1 biosensor, C. elegans embryo assay |
Cell Reports |
High |
27068477
|
| 2016 |
DNA damage inhibits Plk1 activity at T210 by perturbing Aurora A recruitment to the Bora-Plk1 complex, rather than by disrupting the Bora-Plk1 interaction itself. A direct Aurora A-Bora fusion protein prevents DNA-damage-induced loss of Plk1 T210 phosphorylation, demonstrating that the DDR targets Aurora A-Bora association. |
FRET-based Plk1 activity biosensor, Aurora A-Bora fusion construct, Co-IP, phospho-specific immunoblot for T210 |
Oncogene |
High |
27721411
|
| 2018 |
Cyclin A/Cdk1 phosphorylates Bora to promote Aurora A-dependent Plk1 activation and mitotic entry; phosphorylation of a specific site in Bora by Cyclin A/Cdk1 is both necessary and sufficient for mitotic commitment, constituting the triggering event for the cyclin B/Cdk1 bistable switch. |
In vitro kinase assay (Cyclin A/Cdk1 on Bora, Aurora A on Plk1), site-directed mutagenesis, Xenopus egg extract complementation, mathematical modeling |
Developmental Cell |
High |
29870721
|
| 2021 |
Phospho-Bora (phosphorylated by CyclinA/B-Cdk1 at Ser112) is a direct activator of Aurora A kinase activity; the phospho-Ser112-Pro motif within a TPX2-like region substitutes in trans for Aurora A T288 activation-loop phosphorylation to stabilize the active kinase conformation. Two short TPX2-like motifs and pSer112 in the first ~100 aa of Bora are the key determinants. |
In vitro kinase assay, site-directed mutagenesis, NMR spectroscopy, structural modeling, Xenopus egg extract reconstitution, human cell functional assay |
Nature Communications |
High |
33771996
|
| 2015 |
Bora specifically interacts with the tandem BRCT domain of MDC1 in a phosphorylation-dependent manner after irradiation; overexpression of Bora abolishes irradiation-induced MDC1 foci formation, and Bora knockdown accelerates DSB repair, conferring radioresistance. |
Co-IP of Bora with MDC1, clonogenic survival assay, γH2AX foci assay, knockdown by siRNA |
PLOS ONE |
Medium |
25742493
|
| 2013 |
Bora localizes to meiotic spindles in mouse oocytes (co-localizing with α-tubulin at prometaphase/metaphase but dissociating at anaphase/telophase); depletion or inhibition of Bora causes defective spindle morphology, chromosome misalignment, and arrest at prometaphase/metaphase-I, with loss of Aurora A and Plk1 at the spindle. |
Immunofluorescence co-localization, siRNA microinjection, anti-Bora antibody microinjection, live imaging of GVBD and polar body extrusion |
Molecular Reproduction and Development |
Medium |
23610072
|
| 2025 |
cAMP-dependent protein kinase (PKA) phosphorylates Bora during G2 phase, enabling Bora to bind Aurora A and recruit it to the Bora-Plk1 complex, thereby facilitating Aurora A-dependent Plk1 activation and G2/M transition. Disruption of PKA-mediated Bora phosphorylation impairs Plk1 activation; a phospho-mimetic Bora mutant bypasses PKA requirement. |
In vitro kinase assay (PKA on Bora), Co-IP of Bora with Aurora A, site-directed mutagenesis (phospho-mimetic and phospho-null Bora), Plk1 activity assay, cell cycle synchronization, DNA damage checkpoint recovery assay |
Nature Communications |
Medium |
40849432
|
| 2026 |
Structural models of the Aurora A/Bora and Aurora A/Bora/PLK1 ternary complex validated by NMR and mutagenesis show that Bora wraps around the N-lobe of Aurora A, with pSer112 mimicking T-loop phosphorylation. In the ternary complex Bora bridges both kinases, orienting PLK1's activation loop toward Aurora A's active site via Bora residues 56-66 engaging a conserved C-helix pocket on PLK1 analogous to the TPX2-binding Y-pocket of Aurora A. Aurora A phosphorylation of Bora Ser59 creates an additional interface that increases PLK1 phosphorylation efficiency. |
NMR spectroscopy, site-specific mutagenesis, in vitro biochemical assay, structural modeling (AlphaFold-based validated models) |
EMBO Reports |
High |
41606264
|
| 2025 |
Bora is the main driver of Plk1 activation for mitotic entry, DNA-damage recovery, and centrosome maturation, while centriole disengagement is primarily regulated by Cep192 and Cenexin, demonstrating that distinct Plk1 co-activators control different cell cycle steps via spatially distinct Plk1 pools in human cells. |
siRNA knockdown of individual Plk1 co-activators (Bora, Cep192, Cenexin), FRET Plk1 biosensor, live-cell imaging, centrosome maturation and centriole disengagement assays |
bioRxivpreprint |
Medium |
|
| 2025 |
Aurora A:Bora complex specifically phosphorylates PLK1 T210 in vitro, whereas Aurora A alone, other Aurora A:activator complexes, and Aurora B:INCENP fail to phosphorylate T210. A transient Bora-PLK1 interaction identified by structural modeling and confirmed by mutagenesis is uniquely required for T210 phosphorylation; mutating PLK1 Lys208 to Arg eliminates Bora dependency and allows phosphorylation by multiple Aurora kinases. |
In vitro kinase assay reconstitution with purified components, structural modeling, site-directed mutagenesis of Bora-PLK1 interface and PLK1 Lys208 |
bioRxivpreprint |
Medium |
|
| 2025 |
Structural modeling (AlphaFold3) and E. coli reconstitution assay show that phospho-Bora wraps around the N-terminal lobe of Aurora A, positioning pSer112 in Aurora A's activation loop to mimic T-loop phosphorylation; Bora additionally bridges Aurora A activity to the PLK1 T-loop via a conserved motif interacting with the PLK1 alpha-C helix, which is otherwise impervious to Aurora A phosphorylation. |
E. coli-based reconstitution of Bora-Aurora A-dependent Plk1 T-loop phosphorylation (MITOKINAC), AlphaFold3 structural modeling, 39-variant mutagenesis panel, Xenopus egg extract assay |
bioRxivpreprint |
Medium |
|