| 1999 |
Human PEX5 binds the N-terminal fragment of PEX14-(1-78) with very high affinity in the low nanomolar range, as measured by surface plasmon resonance. PEX5 possesses multiple binding sites for PEX14 distributed throughout its N-terminal half, and a pentapeptide motif reiterated seven times in PEX5 was identified as the determinant for interaction with PEX14. |
Surface plasmon resonance, in vitro binding assay with recombinant proteins, sizing chromatography |
The Journal of biological chemistry |
High |
10026185
|
| 1997 |
H. polymorpha Pex14p is a peroxisomal membrane protein essential for import of matrix proteins; loss of Pex14p results in peroxisomal membrane remnants containing only small amounts of matrix proteins (AO, catalase, DHAS), with the bulk mislocalized to the cytosol. Overproduction of Pex14p causes a peroxisome-deficient phenotype with numerous small vesicles lacking matrix proteins, indicating stoichiometry of Pex14p relative to other biogenesis components is critical. |
Genetic complementation, biochemical fractionation, electron microscopy, gene disruption |
The EMBO journal |
High |
9009266
|
| 2001 |
The seven di-aromatic pentapeptide repeat motifs (WX(E/D/Q/A/S)(E/D/Q)(F/Y)) of human PEX5 each independently bind to the same site in the N-terminus of PEX14 with equilibrium dissociation constants in the low nanomolar range. Mutational analysis showed the conserved aromatic amino acids at positions 1 and 5 of the motif are essential for high affinity binding, proposed to form hydrophobic anchors via an amphipathic alpha-helix. |
Two-hybrid analysis in mammalian cells, in vitro binding assays, mutational analysis, surface plasmon resonance |
The Journal of biological chemistry |
High |
11438541
|
| 2009 |
The N-terminal domain of Pex14 (Pex14-N) adopts a three-helical fold. Both PEX5 and PEX19 ligand helices bind competitively to the same surface of Pex14-N, but with opposite directionality. The Pex5 WxxxF/Y motif and a newly identified F/YFxxxF sequence in Pex19 mediate this recognition through conserved aromatic side chains. Mutations of Pex14 residues in the Pex5/Pex19 binding region disrupt binding in vitro and impair peroxisomal membrane localization of Pex14 in vivo. |
NMR structure determination, in vitro binding assays, site-directed mutagenesis, in vivo localization |
The EMBO journal |
High |
19197237
|
| 2011 |
Human PEX14 interacts directly with tubulin, and this binding is mediated by the conserved N-terminal domain of PEX14. PEX14-deficient cells lose the ability of peroxisomal remnants to move along microtubules, establishing PEX14 as the membrane anchor linking peroxisomes to microtubules for motility. |
Affinity purification of native PEX14 complexes, mass spectrometry, size-exclusion chromatography, in vitro binding, live cell imaging, PEX14-deficient cell analysis |
Journal of cell science |
High |
21525035
|
| 2011 |
PEX5 binds monomeric catalase and potently inhibits its tetramerization; no such complex was detected with tetrameric catalase. The N-terminal domain of PEX14 disrupts the PEX5-catalase interaction, with one or two of the seven PEX14-binding diaromatic motifs of PEX5 involved, indicating PEX14 participates in the cargo protein release step. |
In vitro binding assays, biochemical reconstitution, domain deletion analysis |
The Journal of biological chemistry |
High |
21976670
|
| 2013 |
A novel PEX5-PEX14 interaction site in PEX5 with the sequence LVAEF (consensus LVXEF) was identified. NMR structure of the Pex5-(57-71)/Pex14-NTD complex showed this motif binds in a similar alpha-helical orientation as the WxxxF/Y motif but with the tryptophan pocket occupied by leucine. The LVXEF motif has 33-fold faster dissociation from PEX14 than WxxxF/Y motifs, and alanine substitution of LVAEF strongly impairs peroxisomal matrix protein import in vivo. |
Peptide library ligand blot screening, NMR structure determination, surface plasmon resonance, mutagenesis, in vivo import assays |
The Journal of biological chemistry |
High |
24235149
|
| 2020 |
Pex14 is phosphorylated at Ser232 in response to H2O2-induced oxidative stress in mammalian cells. This phosphorylation suppresses peroxisomal import of catalase specifically (but not canonical PTS1 proteins) by selectively impairing the interaction of catalase with the Pex14-Pex5 complex in vitro. A phosphomimetic Pex14-S232D mutant elevates cytosolic catalase and confers higher cell resistance to H2O2. |
Phosphoproteomics, site-directed mutagenesis (S232D phosphomimetic), in vivo import assays, in vitro binding assays |
eLife |
High |
32831175
|
| 2007 |
Hansenula polymorpha Pex14 has a unique dual function: it is required both for matrix protein import into peroxisomes and for selective autophagic degradation of peroxisomes (pexophagy). Other components of the peroxisomal translocon (Pex2, Pex10, Pex12, Pex13, Pex17) are not required for pexophagy, making Pex14 the sole peroxisomal translocon component with this dual function. |
Genetic epistasis analysis with multiple pex deletion mutants, pexophagy assays |
Autophagy |
Medium |
17921697
|
| 2005 |
Pex13 binds Pex14 via two sites: its SH3 domain and a novel intraperoxisomal site. Pex5 also contributes to the association of Pex13 with Pex14. Combining mutations in the novel Pex14-interaction site of Pex13 with a non-Pex13-interacting Pex5(W204A) mutant severely compromised PTS1-dependent import; additionally blocking the SH3-Pex14 interaction completely abrogated PTS2-dependent import and dissociated Pex13 from the docking complex. |
In vitro binding assays, genetic epistasis with combined mutants, co-purification, growth assays on oleic acid |
Molecular and cellular biology |
High |
15798189
|
| 2000 |
In H. polymorpha Δpex14 cells, overproduction of the PTS1 receptor Pex5p leads to enhanced import of PTS1 proteins AO and DHAS but not PTS2 protein amine oxidase, and not catalase. Pex5p localizes to the cytosol and outer peroxisomal membrane surface in Δpex14 cells, indicating that Pex5p can bind the peroxisomal membrane and mediate partial import of certain PTS1 proteins in the absence of Pex14p. |
Genetic overexpression in pex14 null mutant, subcellular fractionation, immunofluorescence |
The Journal of biological chemistry |
Medium |
10777551
|
| 2018 |
PEX14 is a bona fide intrinsic membrane protein with Nin-Cout topology (N-terminus facing the peroxisomal lumen, C-terminus facing the cytosol), as determined in proteoliposomes and purified rat liver peroxisomes. |
Protease-protection assays on proteoliposomes and native peroxisomes, mass spectrometry, Edman degradation, western blotting with domain-specific antibodies |
The FEBS journal |
High |
30414318
|
| 2021 |
The PEX14 N-terminal domain (NTD) binds to microtubular filaments in vitro with nanomolar affinity, interacting with two motifs in the C-terminal region of human β-tubulin. PEX5 competes with β-tubulin for binding to PEX14-NTD, such that PEX5 binding to PEX14 can prevent peroxisome anchoring to microtubules, providing a mechanistic link between peroxisomal protein import and motility. |
In vitro binding assays, NMR spectroscopy, competition binding experiments, dissociation constant measurement |
Journal of molecular biology |
High |
33484719
|
| 2021 |
The PEX14 NTD weakly interacts with membrane-mimicking bicelles via a surface that partially overlaps with the WxxxF/Y binding site. The PEX5-PEX14 NTD interaction is largely unaffected by the presence of membranes, with reduced binding enthalpy compensated by reduced entropy loss, indicating docking of PEX5 to PEX14 at the membrane does not reduce overall binding affinity. |
NMR spectroscopy with bicelles and nanodiscs, isothermal titration calorimetry (ITC) |
Frontiers in cell and developmental biology |
Medium |
33937250
|
| 2017 |
Small molecules disrupting the Trypanosoma PEX14-PEX5 protein-protein interaction cause mislocalization of glycosomal enzymes, metabolic catastrophe, and parasite death. High-resolution X-ray crystal structures of inhibitors bound to TbPEX14 were obtained, revealing the structural basis for blocking PEX14-PEX5 interaction as a drug target. |
X-ray crystallography of inhibitor-PEX14 complexes, NMR binding studies, cell-based trypanocidal assays |
Science |
High |
28360328
|
| 2003 |
T. brucei PEX14 is associated with glycosomes and its N-terminal part binds specifically to TbPEX5. RNAi-mediated depletion of TbPEX14 causes mislocalization of glycosomal proteins (PTS1, PTS2, and internal I-PTS-containing) to the cytosol and is essential for survival of both bloodstream-form and procyclic trypanosomes. |
Subcellular fractionation, in vitro binding with recombinant proteins, RNA interference, immunofluorescence |
European journal of biochemistry |
High |
12709066
|
| 2004 |
Human PEX14 is required for both PTS1- and PTS2-dependent peroxisomal matrix protein import in human cells. Loss-of-function (nonsense mutation p.Q185X) causes Zellweger syndrome; transfection with wild-type PEX14 rescued import in patient fibroblasts, establishing PEX14 as the 13th complementation group gene for peroxisome biogenesis disorders. |
Genetic complementation in patient fibroblasts, immunocytochemistry, mutational analysis |
Human mutation |
Medium |
15146459
|
| 2009 |
Solution structure of the human Pex5-Pex14-PTS1 complex determined by small angle X-ray scattering reveals a 1:6 stoichiometry for the Pex5-Pex14 complex. The N-terminus of Pex5 remains extended in the presence of cargo and Pex14, with Pex14 significantly intermingled with the Pex5 moiety. |
Small angle X-ray scattering (SAXS), static light scattering, titration studies |
The Journal of biological chemistry |
Medium |
19584060
|
| 2025 |
The C-terminal domain (CTD) of human PEX14 undergoes phase separation in vitro, forming condensates that recruit PEX5-cargo complexes carrying PTS1 or PTS2 signals. hPEX14 forms tetramers, and hPEX14 and hPEX13 form immiscible condensates. Replacing hPEX14 CTD with other phase-separating polypeptides partially restores peroxisomal import; electrostatic interactions and the specific CTD sequence are essential for import. |
In vitro phase separation assays, structural analysis of PEX14 tetramer, domain replacement experiments, cargo recruitment assays |
Nature structural & molecular biology |
High |
40555785
|
| 2025 |
PEX14 acts as a docking site for the autophagy receptor optineurin (OPTN) on the peroxisomal membrane, enabling OPTN-mediated pexophagy. PEX14 and OPTN interact through their coiled-coil and ubiquitin-binding domains, respectively. PEX14-OPTN complexes colocalize with LC3, and bafilomycin A1 suppresses OPTN-mediated peroxisome degradation. |
Proximity labeling, co-immunoprecipitation, domain mapping, fluorescence microscopy, autophagy inhibitor treatment |
The Journal of cell biology |
Medium |
41071103
|
| 2026 |
The N-terminal domain of Pex14 undergoes ATP- and ubiquitination-dependent topological remodeling regulated by the AAA+ ATPase Pex6 and its membrane-recruiting partner Pex26. Under normal conditions, the Pex14 N-terminus is oriented toward the peroxisomal lumen; deficiency of Pex6 or Pex26, or pharmacological inhibition of AAA+ ATPases, causes the N-terminus to become exposed to the cytoplasm. Inhibition of ubiquitin activation blocks this reorientation, likely by preventing Pex5 ubiquitination and extraction. |
Immunofluorescence microscopy, protease protection assays, pharmacological inhibition of AAA+ ATPases, ubiquitin pathway inhibition |
The Journal of biological chemistry |
Medium |
41581879
|
| 2005 |
In procyclic T. brucei, RNAi knockdown of PEX14 causes mislocalization of glycosomal enzymes and cell death that is triggered by glucose or fructose, but not in the absence of sugars. Double RNAi of PEX14 and hexokinase rescued cells from glucose toxicity even though glycosomal proteins remained mislocalized, establishing that the toxicity of PEX14 depletion in glucose is due to unregulated cytosolic glycolysis. |
RNA interference (single and double knockdown), genetic epistasis, cell viability assays with different carbon sources |
The Journal of biological chemistry |
Medium |
15637070
|