| 2000 |
CPAP (centrosomal P4.1-associated protein) was identified as a novel centrosomal protein that interacts with the head domain of 4.1R-135 via yeast two-hybrid, co-sediments with gamma-tubulin in sucrose gradients, and co-immunoprecipitates with gamma-tubulin, indicating it is part of the gamma-tubulin complex. Anti-CPAP antibody significantly inhibited formation of microtubule asters, demonstrating a role in microtubule nucleation. |
Yeast two-hybrid, sucrose gradient co-sedimentation, co-immunoprecipitation, immunofluorescence, antibody inhibition assay |
Molecular and cellular biology |
Medium |
11003675
|
| 2002 |
CPAP interacts specifically with Stat5a and Stat5b (but not Stat1 or Stat3) via yeast two-hybrid screening. CPAP augments Stat5-mediated transcription and translocates to the nucleus upon PRL pathway activation, acting as a transcriptional coactivator of Stat5. |
Yeast two-hybrid, co-immunoprecipitation, reporter transcription assay, immunofluorescence, cellular fractionation |
Molecular endocrinology |
Medium |
12198240
|
| 2004 |
CPAP contains a novel 112-residue microtubule-destabilizing motif (MDD, residues 311–422) that binds tubulin heterodimers, inhibits microtubule nucleation from the centrosome, depolymerizes taxol-stabilized microtubules, and when overexpressed induces G2/M arrest and apoptosis. |
Deletion mapping, in vitro microtubule depolymerization assay, tubulin-binding assay, tetracycline-controlled overexpression, cell cycle analysis |
Molecular biology of the cell |
High |
15047868
|
| 2005 |
CPAP (CENPJ) localizes to spindle poles of mitotic cells during neuroepithelial neurogenesis; homozygous loss-of-function mutations in CENPJ cause primary microcephaly (MCPH6), implicating a centrosomal mechanism in controlling neuron number. |
Genetic mapping, mutation analysis, immunofluorescence localization in human tissue |
Nature genetics |
Medium |
15793586
|
| 2005 |
RNAi-mediated depletion of CPAP in human cells arrests cells in mitosis, induces apoptosis, and causes multipolar spindle formation in >40% of mitotic cells. Inhibition of kinesin Eg5 in CPAP-depleted cells results in monopolar spindles, indicating Eg5 is required downstream of CPAP for multipolar spindle formation, revealing a structural role for CPAP in centrosome integrity. |
siRNA knockdown, immunofluorescence, Eg5 inhibition epistasis |
Biochemical and biophysical research communications |
Medium |
16316625
|
| 2008 |
The microtubule-binding domain (MBD, residues 423–607) of CPAP is located adjacent to its microtubule-destabilizing domain (MDD, residues 311–422). Point mutations disrupting alpha-helical structure (Y341P, I346P, L348P, triple-P) or charge (KR377EE) in the MDD abolish MT-destabilizing activity and significantly reduce tubulin heterodimer binding. The conserved ~20-aa sequence in Drosophila d-SAS-4 functions similarly. |
Site-specific mutagenesis, in vitro microtubule binding and destabilization assays, truncation analysis |
Experimental cell research |
High |
18586240
|
| 2009 |
CPAP protein levels are cell-cycle regulated, being degraded in late mitosis. Excess CPAP induces formation of elongated procentriole-like structures (PLSs) containing stable microtubules and centriolar proteins. A tubulin-binding-defective mutant (CPAP-377EE) fails to induce PLSs, demonstrating that CPAP's intrinsic tubulin-dimer binding activity is required for procentriole elongation. |
Cell cycle analysis, siRNA knockdown, overexpression, immunofluorescence, ultrastructural EM analysis, mutagenesis |
Nature cell biology |
High |
19503075
|
| 2009 |
Overexpression of CPAP in human cells leads to abnormally long centrioles and formation of supernumerary procentrioles, resulting in multipolar spindle assembly and cytokinesis defects. CPAP is required for centrosome duplication in cycling human cells. |
Overexpression, siRNA knockdown, immunofluorescence, time-lapse microscopy |
Current biology : CB |
High |
19481460
|
| 2009 |
CPAP and CP110 play antagonistic roles in controlling centriole length: CPAP overexpression enhances centriolar tubulin accumulation leading to elongated centrioles, while CP110 depletion produces elongated MT structures that are distinct from primary cilia. |
Overexpression, siRNA depletion, immunofluorescence, electron microscopy |
Current biology : CB |
High |
19481458
|
| 2009 |
CPAP forms homodimers via its fifth coiled-coil domain during interphase. This self-interaction is required for maintaining centrosome cohesion and preventing premature centrosome splitting before G2/M. CPAP is phosphorylated during mitosis, and this phosphorylation disrupts the homodimer interaction to allow centrosome splitting. |
Co-immunoprecipitation, domain deletion analysis, immunofluorescence, cell cycle analysis |
The Journal of biological chemistry |
Medium |
19889632
|
| 2010 |
PLK2 phosphorylates CPAP at S589 and S595 in vitro and in vivo. This phosphorylation is critical for procentriole formation during the centrosome cycle; phosphorylated CPAP preferentially localizes to procentrioles. PLK4 also phosphorylates S595 but this is not critical for PLK4-driven procentriole assembly. Overexpression of phospho-resistant CPAP mutant inhibits elongated centriole formation. |
In vitro kinase assay, in vivo phosphorylation (mass spectrometry/western), site-directed mutagenesis, immunofluorescence, overexpression |
The EMBO journal |
High |
20531387
|
| 2010 |
Cep152 directly interacts with CPAP and is required for recruitment of CPAP to the centrosome. Reduction of Cep152 causes loss of CPAP from centrosomes, failure of centriole duplication, and monopolar spindle formation. |
Co-immunoprecipitation, siRNA knockdown, immunofluorescence |
The Journal of cell biology |
Medium |
21059844
|
| 2011 |
Drosophila Sas-4 provides a scaffold for cytoplasmic complexes (S-CAP) including CNN, Asl, and D-PLP. In the absence of Sas-4, nascent procentrioles are unstable and lack PCM. When Sas-4 cannot form S-CAP complexes, centrosomes have dramatically reduced PCM. Purified S-CAP complexes or recombinant Sas-4 can bind centrosomes stripped of PCM, demonstrating that Sas-4 tethers pre-assembled PCM complexes to centrioles. |
Genetic null and point mutant analysis, mass spectrometry, in vitro binding with purified proteins, immunofluorescence |
Nature communications |
High |
21694707
|
| 2011 |
Human STIL directly interacts with CPAP and forms a complex with hSAS6. A microcephaly-causing CPAP mutation (E1235V) significantly reduces binding to STIL. STIL depletion inhibits centriole duplication, Plk4-induced centriole amplification, and CPAP-induced centriole elongation, and blocks localization of hSAS6 and CPAP to the nascent procentriole base. |
Co-immunoprecipitation, direct interaction assay, siRNA knockdown, immunofluorescence, MCPH mutation analysis |
The EMBO journal |
High |
22020124
|
| 2011 |
CPAP protein domains required for centriolar localization, centriole elongation, and centriole formation were identified. Conditions mimicking CPAP MCPH patient mutations impair centriole formation in tissue culture cells and correlate with randomization of spindle position on adhesive micropatterns. STIL is also essential for centriole formation and proper spindle positioning. |
Domain deletion mutagenesis, siRNA knockdown, immunofluorescence, adhesive micropattern spindle orientation assay |
Journal of cell science |
Medium |
22100914
|
| 2012 |
Tankyrase 1 PARsylates CPAP in vitro and in vivo, targeting it for proteasomal degradation. Overexpression of tankyrase 1 leads to CPAP degradation and prevents centriole duplication; depletion of tankyrase 1 stabilizes CPAP in G1, generating elongated procentrioles and multipolarity. Tankyrase 1 localizes to centrosomes exclusively in G1, coinciding with CPAP degradation. |
In vitro PARsylation assay, co-immunoprecipitation, siRNA knockdown, overexpression, immunofluorescence, proteasome inhibitor treatment |
EMBO reports |
High |
22699936
|
| 2012 |
CPAP is required for cilia biogenesis in neuronal CAD cells and hippocampal neurons. Overexpression of wild-type CPAP promotes cilia formation and longer cilia. The tubulin-binding-defective mutant CPAP-377EE inhibits cilia formation and causes cilia shortening. Depletion of CPAP inhibits ciliogenesis, rescued by wild-type but not CPAP-377EE. |
siRNA knockdown, overexpression, mutagenesis (CPAP-377EE), immunofluorescence in neuronal cell lines and primary neurons |
Biology open |
Medium |
23213448
|
| 2012 |
Mouse Cenpj hypomorphic allele recapitulates Seckel syndrome features. Cenpj-deficient embryonic fibroblasts exhibit irregular centriole and centrosome numbers, mono- and multipolar spindles, and near-tetraploidy. Genomic instability arises from mitotic failure rather than defective ATR-dependent DNA damage signaling. |
Hypomorphic mouse model, immunohistochemistry, centrosome counting, karyotyping, ATR pathway analysis |
PLoS genetics |
Medium |
23166506
|
| 2013 |
Crystal structures of the CPAP TCP domain in complex with a conserved STIL fragment reveal that the TCP domain is a novel proline recognition domain forming a 1:1 complex with STIL. The TCP domain adopts an all-β structure. A microcephaly mutation in CPAP (E1235V) maps to the STIL-binding interface and compromises complex formation. Point mutations abolishing complex formation block centriole duplication in vivo. |
X-ray crystallography, ITC binding assay, site-directed mutagenesis, in vivo centriole duplication assay |
eLife |
High |
24052813
|
| 2013 |
CEP135 directly interacts with hSAS-6 via its C-terminus and with CPAP via its N-terminal domain. CEP135 depletion perturbs CPAP centriolar localization and blocks CPAP-induced centriole elongation. Overexpression of a CEP135 mutant lacking hSAS-6 binding has a dominant-negative effect on centriole assembly. CEP135 acts as a linker connecting hSAS-6 to outer centriolar microtubules and is required for CPAP-mediated centriole elongation. |
Co-immunoprecipitation, direct binding assays, siRNA knockdown, overexpression, dominant-negative mutant, immunofluorescence, EM |
The EMBO journal |
High |
23511974
|
| 2013 |
The G-box (TCP) domain of CPAP adopts a single elongated β-sheet capable of forming supramolecular assemblies. The G-box structure was determined alone and in complex with a STIL fragment. The conserved CPAP-STIL complex is confirmed by structural and biophysical studies. A microcephaly missense mutation in the G-box reduces affinity for STIL. CPAP is proposed to act as a horizontal strut joining the centriolar scaffold with microtubules. |
X-ray crystallography, NMR, biophysical binding assays (ITC/SPR), mutagenesis |
Structure |
High |
24076405
|
| 2013 |
CPAP is SUMOylated by SUMO-1 upon TNF-α stimulus, and this SUMOylation is essential for its NF-κB co-activator activity. CPAP siRNA abolishes the interaction between IKKβ and NF-κB, while CPAP overexpression enhances IKKβ–NF-κB interaction and augments NF-κB activation. SUMO-deficient CPAP mutant loses co-activator activity and fails to enter the nucleus. SUMOylated CPAP synergistically increases HBx-induced NF-κB activity. |
In situ PLA assay, reporter assay, RT-PCR, siRNA knockdown, overexpression, western blot, in vivo SUMO modification assay |
Journal of hepatology |
Medium |
23369793
|
| 2014 |
The crystal structure of the Sas-4/CPAP TCP domain reveals a solvent-exposed single-layer β-sheet fold that provides an extended surface platform for tethering the Sas-4-PCM scaffold to centrioles. Point mutations in β-strands 9–10 (including an MCPH-associated mutation) perturb PCM tethering while allowing Sas-4/CPAP to scaffold cytoplasmic PCM complexes. The β9-10 surface mediates interactions with Ana2 and Bld-10 for efficient centriole tethering. |
X-ray crystallography, site-directed mutagenesis, Drosophila genetics, human cell functional assays, iPSC-derived neural progenitor cell assays |
Proceedings of the National Academy of Sciences of the United States of America |
High |
24385583
|
| 2014 |
Centrobin interacts with CPAP and is required for CPAP localization to centrioles during centriole duplication. Centrobin depletion causes disappearance of CPAP from centrioles and its proteasome-mediated degradation; centrobin protects ubiquitinated CPAP from degradation. Restoration of centrobin expression restores centriolar CPAP. The CPAP-binding fragment of centrobin acts as a dominant negative to displace centriolar CPAP. |
Co-immunoprecipitation, siRNA knockdown, overexpression, dominant-negative fragment, proteasome inhibitor treatment, immunofluorescence |
The Journal of biological chemistry |
Medium |
24700465
|
| 2015 |
Centrobin controls CPAP levels and centriole elongation: centrobin overexpression causes massive CPAP accumulation and abnormal centriole elongation; centrobin depletion causes CPAP undetectability via ubiquitin-proteasome degradation. Only full-length centrobin (not CPAP-binding-defective mutant) restores CPAP levels. Centrobin-overexpressing cells show proteasome-independent accumulation of ubiquitinated CPAP. |
siRNA knockdown, overexpression, mutagenesis, proteasome inhibitor treatment, immunofluorescence |
The Journal of biological chemistry |
Medium |
25616662
|
| 2015 |
CPAP (Cenpj) is a transcriptional target of proneural factor Ascl1 in the embryonic cerebral cortex. Knockdown of Cenpj by in utero electroporation disrupts centrosome biogenesis and randomizes cleavage plane orientation of radial glia progenitors. In post-mitotic neurons, Cenpj downregulation increases stable microtubules, slows neuronal migration, and causes aberrant centrosome position and morphology. Rescue experiments show Cenpj mediates Ascl1's role in centrosome biogenesis and microtubule dynamics. |
In utero electroporation knockdown, rescue experiments, immunofluorescence, chromatin immunoprecipitation (Ascl1 binding to Cenpj promoter) |
Nature communications |
Medium |
25753651
|
| 2016 |
CPAP (SAS-4) binds and caps microtubule plus ends by associating with a site on β-tubulin engaged in longitudinal tubulin-tubulin interactions. This capping dampens microtubule growth and stabilizes microtubules by inhibiting catastrophes and promoting rescues. Crystallographic, biophysical (TIRF reconstitution), and in-cell assays demonstrate that CPAP's capping function limits growth of centriolar microtubules. |
X-ray crystallography, TIRF-based single-molecule reconstitution assay, biophysical binding assays, in-cell functional assays |
Developmental cell |
High |
27219064
|
| 2016 |
CPAP PN2-3 domain forms a high-affinity complex with GTP-tubulin: a C-terminal loop-helix targets β-tubulin at the MT outer surface while an N-terminal helical motif caps the α-β surface of β-tubulin. CPAP(F375A) with strongly reduced tubulin interaction causes shorter centrioles with doublet- instead of triplet-microtubules. CPAP(EE343RR) with slightly reduced affinity but unmasked β-tubulin polymerization surface causes over-elongation of centriolar/ciliary microtubules via enhanced dynamic release of bound tubulin ('clutch-like' mechanism). |
X-ray crystallography, ITC binding assays, site-directed mutagenesis, centriole length measurements, electron microscopy |
Nature communications |
High |
27306797
|
| 2016 |
CPAP is phosphorylated by Aurora-A at serine 467 during mitosis. This phosphorylation is required for maintaining spindle pole integrity; non-phosphorylatable CPAP-S467A fails to rescue PCM dispersion upon CPAP depletion, while phospho-mimic CPAP-S467D rescues it. CPAP-S467D has low affinity for microtubule binding but high affinity for PCM proteins, linking Aurora-A phosphorylation to PCM organization. |
In vitro kinase assay, co-immunoprecipitation, site-directed mutagenesis (S467A/S467D), siRNA knockdown, immunofluorescence |
Cell reports |
High |
26997271
|
| 2016 |
In Drosophila, Cdk1 phosphorylates Sas-4 during mitosis, creating a Polo-docking site that recruits Polo to daughter centrioles. This is required for subsequent recruitment of Asterless (Asl) and for centriole conversion (allowing daughter centrioles to duplicate and organize centrosomes). Point mutations preventing Cdk1 phosphorylation or Polo docking block centriole conversion and lead to embryonic lethality. |
In vitro kinase assay, site-directed mutagenesis, Drosophila genetics, immunofluorescence, time-lapse imaging |
Developmental cell |
High |
27326932
|
| 2016 |
CPAP acts as a negative regulator of ciliary length independent of its role in centrosome biogenesis. At the onset of cilium disassembly, CPAP provides a scaffold for the cilium disassembly complex (CDC) comprising Nde1, Aurora A, and OFD1, recruiting them to the ciliary base for timely cilium disassembly. A Seckel syndrome CPAP mutation fails to localize at the ciliary base, causing inefficient CDC recruitment, long cilia, retarded cilium disassembly, and delayed cell cycle re-entry leading to premature NPC differentiation. |
iPSC-derived neural progenitor cells, patient-derived cells, immunofluorescence, co-immunoprecipitation, brain organoids |
The EMBO journal |
High |
26929011
|
| 2013 |
CEP120 directly interacts with CPAP and positively regulates centriole elongation. CEP120 is a cell-cycle-regulated protein peaking at S to G2/M. Forced overexpression of either CEP120 or CPAP induces overly long centrioles and atypical supernumerary centrioles. Depletion of CEP120 inhibits CPAP-induced centriole elongation and vice versa. A microtubule-binding-defective CEP120-K76A mutant suppresses elongated centriole formation. |
Co-immunoprecipitation, siRNA knockdown, overexpression, mutagenesis (K76A), immunofluorescence |
The Journal of cell biology |
Medium |
23857771
|
| 2018 |
Tubulin interacts with CPAP to negatively regulate CPAP-dependent PCM recruitment and microtubule nucleation. A small molecule CCB02 selectively binds at the CPAP-binding site of tubulin, perturbing CPAP-tubulin interaction. Perturbation of CPAP-tubulin interaction activates extra centrosomes to nucleate enhanced microtubules, causing centrosome de-clustering, multipolar mitosis, and cell death in centrosome-amplified cancer cells. |
Compound screening, co-immunoprecipitation, genetic perturbation, 3D-organotypic invasion assay, immunofluorescence, in vitro binding assay |
The EMBO journal |
Medium |
30530478
|
| 2018 |
In Drosophila, Plk1/Polo kinase phosphorylates Sas-4 in vitro at the onset of mitosis, enabling Sas-4's localization to expand outward from centrosomes. This phosphorylation is required for efficient recruitment of Cnn and γ-tubulin (PCM proteins essential for PCM expansion). Point mutations at Plk1/Polo sites reduce affinity for Cnn and γ-tubulin without affecting centrosome structure or centriole duplication. |
In vitro kinase assay, site-directed mutagenesis, Drosophila genetics, immunofluorescence |
Cell reports |
High |
30590037
|
| 2019 |
CPAP acts as a transcriptional coactivator of STAT3 by directly binding to STAT3. CPAP overexpression upregulates STAT3 target genes IL-8 and CD44 involved in angiogenesis. Knockdown of CPAP impairs IL-6-mediated STAT3 activation, target gene expression, cell migration, and invasion. Interrupting the CPAP-STAT3 interaction attenuates STAT3-mediated tumor growth and angiogenesis. |
Co-immunoprecipitation, reporter assay, siRNA knockdown, overexpression, in vivo xenograft, migration/invasion assay |
Cell death and differentiation |
Medium |
31511651
|
| 2019 |
HBx transcriptionally upregulates CPAP via interacting with CREB at the CPAP promoter (ChIP). Overexpressed CPAP directly interacts with HBx (Co-IP and PLA). SUMO modification of CPAP is required for CPAP-HBx interaction. Overexpressed CPAP maintains HBx protein stability in an NF-κB-dependent manner. |
Chromatin immunoprecipitation, co-immunoprecipitation, in situ PLA, reporter assay, siRNA knockdown, overexpression |
Journal of biomedical science |
Medium |
31170980
|
| 2019 |
Cenpj regulates cilia disassembly in mouse neural progenitor cells through Kif2a (a plus-end-directed motor protein). Conditional Cenpj depletion leads to long cilia and abnormal cilia disassembly. Reduced cell proliferation, uncompleted cell division, and apoptosis result in microcephaly. Cenpj also regulates cilium structure of adult neural stem cells. |
Conditional knockout mice, in vivo immunofluorescence, epistasis with Kif2a, BrdU proliferation assay |
The Journal of neuroscience |
Medium |
30626697
|
| 2020 |
Conditional knockout of Cpap in mouse CNS preferentially induces monopolar spindles in radial glia progenitors (RGPs) at ~E14.5, causing robust apoptosis. Loss of one p53 allele reduces RGP death, and complete p53 removal rescues RGP death, placing CPAP-loss-induced apoptosis downstream of p53. Cpap deletion also causes cilia loss, RGP mislocalization, junctional integrity disruption, and severe cerebellar hypoplasia. |
Conditional knockout mouse (CNS-specific), genetic epistasis with p53, immunofluorescence, histological analysis |
Journal of cell science |
Medium |
32501282
|
| 2020 |
WDR62 mutant proteins (V66M and R439H) localize to the basal body but fail to recruit CPAP. As a consequence, IFT88 recruitment is deficient, leading to failure of cilia formation. This underpins premature differentiation of radial glia and microcephaly in WDR62 mutant mice. |
CRISPR/Cas9 knock-in mice, immunofluorescence, co-localization studies |
Human molecular genetics |
Medium |
31816041
|
| 2022 |
Using auxin-inducible degron-mediated fast CPAP degradation combined with superresolution microscopy, three independent centrosomal CPAP populations were identified with distinct cell-cycle regulation. CPAP is critical for assembly of human centrioles but not for PCM recruitment onto already-assembled centrioles. CPAP insufficiency leads to centrioles with incomplete microtubule triplets that can still convert to centrosomes, duplicate, and form spindle poles, but ultimately fragment due to loss of cohesion between microtubule blades. |
Auxin-inducible degron fast protein degradation, superresolution microscopy (STORM/STED), live imaging, electron microscopy |
The Journal of cell biology |
High |
35404385
|
| 2022 |
The CPAP-E1235V microcephaly mutant perturbs recruitment of centriolar proteins CEP120, CEP295, CENTROBIN, POC5, and POC1B to nascent centrioles, resulting in short centrioles but long cilia in hiPSC-derived brain organoids. CPAP-E1235V induces p53-dependent neuronal cell death, produces smaller brain organoids, and alters spindle orientation of neuronal progenitor cells causing premature neuronal differentiation. |
CRISPR-Cas9 isogenic hiPSC generation, brain organoids, immunofluorescence, spindle orientation assay, p53 pathway analysis |
Frontiers in cell and developmental biology |
Medium |
35309908
|