| 2003 |
NOXO1 PX domain binds phosphatidylinositol lipids (PtdIns 3,5-P2, PtdIns 5-P, PtdIns 4-P) and mediates constitutive membrane co-localization with Nox1; a point mutation in the PX domain decreases lipid binding, causes cytosolic localization, and inhibits Nox1 activation. Co-transfection of Nox1, NOXO1, and NOXA1 reconstitutes ROS generation in HEK293 cells without agonist stimulation. NOXO1 lacks the autoinhibitory region and phosphorylation sites present in p47phox. |
Co-transfection/reconstitution in HEK293 cells, lipid-binding assays, site-directed mutagenesis of PX domain, co-localization imaging |
The Journal of biological chemistry |
High |
14617635
|
| 2004 |
Nox3 is strongly activated by NOXO1 alone (without NOXA1 or p67phox), unlike gp91phox or Nox1 which require both organizer and activator subunits. Nox3 regulation by p47phox (but not NOXO1) is PMA-dependent, consistent with the phosphorylation-regulated autoinhibitory region present in p47phox but absent in NOXO1. Deletion of the autoinhibitory region from p47phox renders it highly active without PMA but still requires an activator subunit. |
Cell-based reconstitution assay measuring superoxide production with various subunit combinations and mutants |
The Journal of biological chemistry |
High |
15181005
|
| 2005 |
NOXO1 has four splice forms (alpha, beta, gamma, delta) arising from alternative splicing of exon 3 in the PX domain region. NOXO1beta is the major form in colon and fetal liver; NOXO1gamma is the majority in testis. Both NOXO1beta and NOXO1gamma bind phosphoinositide lipids with the same specificity and affinity but differ functionally: NOXO1gamma shows poorer ability to activate Nox3 compared with NOXO1beta, while both activate Nox1 equally. |
RT-PCR/cloning of splice forms, purified PX domain lipid-binding assays, cell-based Nox1/Nox3 reconstitution assays |
Gene |
High |
15949904
|
| 2006 |
NOXO1 contains an intramolecular interaction between its bis-SH3 domain and its C-terminal proline-rich region (PRR); this interaction prevents the SH3 domains from binding p22phox and the PRR from associating with NOXA1. Arachidonic acid enhances SH3-mediated binding of NOXO1 to p22phox, and disruption of the intramolecular SH3-PRR interaction facilitates both p22phox binding and PRR-Noxa1 association required for Nox activation. NOXO1 also supports superoxide production in a cell-free system for gp91phox/Nox2 activation by arachidonic acid. |
Cell-free Nox2 reconstitution assay, pulldown/binding assays with domain mutants, arachidonic acid stimulation |
Biochemical and biophysical research communications |
High |
17126813
|
| 2008 |
TNF-alpha induces NOXO1 transcription through an AP-1 binding site (−561 to −551 bp, agtAAGtcatg) in the NOXO1 promoter, via rapid activation of p38 MAPK and JNK1/2, followed by c-Jun/c-Fos phosphorylation and AP-1 complex formation. TNF-alpha-induced upregulation of superoxide production in T84 colon epithelial cells was abolished by NOXO1 siRNA knockdown. |
Promoter cloning and serial deletion/mutation analysis, AP-1 decoy oligonucleotides, siRNA knockdown, superoxide measurement |
Free radical biology & medicine |
High |
18929641
|
| 2010 |
The isolated tandem SH3 domains of NOXO1 bind to p22phox with high affinity, likely adopting a superSH3 domain conformation. The C-terminal tail of NOXO1 competes for SH3 binding to p22phox and thereby inhibits complex formation, suggesting autoinhibitory regulation of NOX1 activity. The molecular details of NOXO1-NOXA1 interaction differ significantly from those of the homologous p47phox-p67phox interaction. |
Isothermal titration calorimetry (ITC) measuring binding affinity between isolated domains and partner peptides/proteins |
PloS one |
High |
20454568
|
| 2013 |
PMA stimulates NOXO1 phosphorylation at Ser-154 via protein kinase C in HEK293 and T84 colon epithelial cells. Phosphorylation at Ser-154 enhances NOXO1 binding to NOXA1 (+97%) and to p22phox C-terminal region (+384%), increases NOXO1 co-localization with p22phox, and is required for optimal ROS production by NOX1 (demonstrated by S154A and S154D mutants). Pulldown experiments show phospho-Ser154 first enhances NOXO1-NOXA1 binding, which then acts as a molecular switch enabling optimal NOXO1-p22phox interaction. |
Site-directed mutagenesis (S154A, S154D), pulldown assays, co-localization imaging, ROS measurement, endogenous phosphorylation confirmed in T84 cells |
FASEB journal |
High |
23322165
|
| 2013 |
PKC directly phosphorylates NOXO1 at Thr341 in vitro; T341A substitution reduces PMA-induced NOXO1 phosphorylation and PMA-dependent Nox1 superoxide production. Phosphorylation of Thr341 promotes NOXO1 interaction with NOXA1, which is required for Nox1 activation. Additionally, Ser154 is phosphorylated in both resting and PMA-stimulated cells and may be the major PKA phosphorylation site in vitro, contributing to constitutive Nox1 activity. |
In vitro PKC kinase assay, alanine-substitution mutagenesis (T341A), pulldown assays for NOXO1-NOXA1 and NOXO1-p22phox interactions, superoxide measurement |
The FEBS journal |
High |
23957209
|
| 2016 |
Grb2 interacts with NOXO1 and recruits the Cbl E3 ubiquitin ligase, leading to proteasomal degradation of NOXO1 and reduced ROS production. EGF-mediated phosphorylation of NOXO1 causes its release from Grb2 and promotes its association with NOXA1 to stimulate ROS production. Grb2 overexpression decreases Nox1 activity; Grb2 knockdown increases Nox1 activity. CRISPR/Cas9-mediated NoxO1 knockout abrogates anchorage-independent growth and tumor formation in nude mice. |
Co-immunoprecipitation, CRISPR/Cas9 knockout, Grb2 overexpression/knockdown, soft agar colony assay, xenograft tumor assay, protein stability assay |
Cancer research |
High |
26781991
|
| 2016 |
At resting state, NOXO1 co-localizes with NOX1 (distinct from p47phox co-localizing with NOX2) in endothelial cells. RNAi of NOXO1 reduces superoxide and increases NO in response to oscillatory shear stress (OSS) and corrects OSS-induced eNOS uncoupling, while having no effect under laminar shear stress (LSS). This identifies the NOX1-NOXO1 complex as the mediator of OSS-induced eNOS uncoupling. |
Immunocytochemical co-localization, RNAi knockdown, superoxide/NO measurements, eNOS uncoupling assay under defined flow conditions |
The Journal of biological chemistry |
Medium |
26826128
|
| 2016 |
NoxO1 deletion in lung endothelial cells attenuates ADAM17 (α-secretase) activity and Notch intracellular domain release, leading to reduced Notch signaling and a tip-cell phenotype with increased angiogenesis. NoxO1 overexpression promotes ADAM17 oxidation and maximal α-secretase activity, mechanistically linking NoxO1-derived ROS to ADAM17 activation and Notch-dependent stalk cell fate. |
NoxO1 knockout mouse, spheroid outgrowth assay, retinal angiogenesis imaging, femoral artery ligation model, ADAM17 activity assay, Notch signaling readouts in NoxO1-/- LECs |
Arteriosclerosis, thrombosis, and vascular biology |
Medium |
27283741
|
| 2018 |
NoxO1 knockout in mice reduces superoxide production in colon crypts without compensatory p47phox upregulation, and results in increased proliferative capacity and decreased apoptosis of colon epithelial cells, demonstrating a role for NoxO1-dependent ROS in limiting colon epithelial proliferation. |
NoxO1 knockout mouse, superoxide measurement in colon crypts, proliferation and apoptosis assays, DSS colitis and AOM/DSS colon cancer models |
Frontiers in immunology |
Medium |
29867954
|
| 2021 |
CYLD (cylindromatosis deubiquitinase) binds NoxO1, promotes its ubiquitination, and reduces NoxO1 protein half-life, thereby destabilizing NoxO1 and suppressing excessive ROS generation. CRISPR/Cas9-mediated CYLD knockout in PC-3 prostate cancer cells promotes proliferation, migration, colony formation, and invasion, and increases tumor growth in xenograft mice, consistent with CYLD acting as a NoxO1 destabilizer. |
Genome-wide CRISPR/Cas9 DUB-knockout library screen, Co-IP for CYLD-NoxO1 binding, ubiquitination assay, protein half-life measurement, CYLD KO xenograft tumor model |
Cancer letters |
Medium |
34742871
|
| 2023 |
A D-box mutation in NOXO1 (mut1) increases NoxO1 translocation from the membrane-soluble fraction to a cytoskeletal-insoluble fraction, causes a filamentous subcellular phenotype, and associates with intermediate filaments keratin 18 and vimentin; this redistribution correlates with increased Nox1-dependent NADPH oxidase activity and ROS production. |
Expression of wt and D-box mutant NOXO1 in cell lines, subcellular fractionation, co-immunoprecipitation with cytoskeletal proteins, ROS measurement |
International journal of molecular sciences |
Low |
36902094
|
| 2024 |
NoxO1 interacts with Erbin (ErbB2 interacting protein) as identified by BioID proximity labeling; NoxO1 co-localizes with EGFR and Erbin, and EGF treatment disrupts NoxO1-EGFR co-localization. NoxO1 overexpression delays EGF-mediated kinase activation and inhibits EGF-induced wound closure, while NoxO1 KO has the opposite effect, indicating a Nox1-independent scaffolding role for NoxO1 in EGFR signaling. |
BioID proximity labeling, co-localization imaging, NoxO1 overexpression and CRISPR KO, EGF receptor phosphorylation kinetics, wound closure assay |
Redox biology |
Medium |
39426288
|
| 2024 |
The level of ROS production by the Nox1-centered NADPH oxidase complex is dose-dependently regulated by NoxO1 concentration: increasing NoxO1 above stoichiometric levels progressively controls complex activity, indicating that ROS output is regulated by the NoxO1:Nox1:NoxA1 ratio rather than a strict 1:1:1 stoichiometry. |
Stable HEK293 cell lines constitutively expressing Nox1 and NoxA1 transfected with increasing NoxO1 concentrations; ROS measurement |
Antioxidants (Basel, Switzerland) |
Low |
39334772
|
| 2025 |
NoxO1 overexpression expands early endosomes and lysosomes, increases EGFR internalization rates while reducing degradative sorting and lysosomal cargo processing. Mechanistically, NoxO1 activates transcription factor EB (TFEB), the master regulator of lysosomal biogenesis, in an Erbin-dependent but ROS-independent manner. Proximity ligation assays show spatial association of NoxO1, Erbin, EGFR, and TFEB as a multi-protein complex. Genetic ablation of Erbin abolishes NoxO1-induced increases in early endosome (EEA1) and lysosome (LAMP1) markers. |
NoxO1 overexpression and KO cell lines, mathematical ODE modeling of EGFR trafficking, fluorescent cargo (EGF, BSA) trafficking assays, proximity ligation assay, Erbin KO, EEA1/LAMP1 marker quantification, TFEB activity assay |
Redox biology |
Medium |
41406574
|