| 2025 |
Cryo-EM structures of full-length human ABCD3 in apo state (3.33 Å) and bound to phytanoyl-CoA (3.13 Å) reveal that substrate binding brings the two nucleotide-binding domains closer together, stimulating ATPase activity via a substrate-dependent conformational change. This provides a mechanistic basis for substrate-induced ATPase activation and the transport mechanism. |
Cryo-EM structure determination (apo and substrate-bound states) combined with biochemical ATPase activity assays |
bioRxivpreprint |
High |
bio_10.1101_2025.05.21.655323
|
| 2014 |
ABCD3 is required for peroxisomal import and beta-oxidation of branched-chain fatty acids (e.g., pristanic acid) and C27 bile acid intermediates. Loss of ABCD3 (patient with truncating mutation p.Y635NfsX1 and Abcd3-/- mice) leads to accumulation of C27 bile acid intermediates and a bile acid biosynthesis defect, demonstrating ABCD3 is essential for the transport of these substrates into peroxisomes. |
Patient genetic analysis (homozygous deletion), biochemical analysis of patient fibroblasts and plasma, Abcd3 knockout mouse model with phytol loading and bile acid profiling |
Human molecular genetics |
High |
25168382
|
| 2013 |
ABCD3 functions as a homodimer and preferentially transports hydrophilic substrates including long-chain unsaturated fatty acids, long branched-chain fatty acids, and long-chain dicarboxylic fatty acids (as CoA esters) into peroxisomes, with a distinct substrate specificity from ABCD1 and ABCD2. This was established by complementation of the yeast pxa1/pxa2Δ mutant and fatty acid oxidation measurements. |
Yeast complementation assay (pxa1/pxa2Δ mutant rescue) and fatty acid oxidation measurements with multiple substrates |
Biochimica et biophysica acta |
High |
24333844
|
| 2018 |
ABCD3 and the D-bifunctional protein HSD17B4 are essential components of a peroxisomal pathway that can oxidize medium- and long-chain fatty acids (lauric and palmitic acid), including as acylcarnitines. CRISPR-generated ABCD3 KO in HEK-293 cells abolished residual peroxisomal oxidation of these fatty acids when mitochondrial beta-oxidation was inhibited. |
CRISPR-Cas9 knockout of ABCD3 (single and double KO) in HEK-293 cells, acylcarnitine profiling; Hsd17b4 KO mouse model with CPT2 inhibition |
FASEB journal |
High |
30540494
|
| 2002 |
ABCD3 (PMP70) binds ATP tightly in the absence of Mg2+, hydrolyzes it to ADP in the presence of Mg2+, and releases ADP to allow catalytic turnover. Additionally, PMP70 is phosphorylated at a tyrosine residue(s). ATP binding/hydrolysis and phosphorylation are involved in regulation of fatty acid transport into peroxisomes. |
Photoaffinity labeling with 8-azido-[α-32P]ATP and 8-azido-[γ-32P]ATP, Mg2+-dependent hydrolysis assays, vanadate-trapping experiments, immunoprecipitation from rat liver peroxisomes |
The Journal of biological chemistry |
Medium |
12176987
|
| 2007 |
ABCD3 (PMP70) forms homodimers in living cells, and also forms heterodimers with ALDP (ABCD1) in vivo. ALDP homodimers predominate. The last 87 C-terminal amino acids of ALDP are the primary domain mediating these interactions, with the N-terminal transmembrane region providing additional stabilization of ALDP homodimers. |
FRET microscopy in intact living cells using fluorescently tagged constructs, C-terminal deletion constructs, statistical analysis by probability distribution shift and Kolmogorov-Smirnov analysis |
The Journal of biological chemistry |
High |
17609205
|
| 2004 |
In mouse liver, PMP70 (ABCD3) and ALDP (ABCD1) exist predominantly as homomeric complexes, with no evidence of heteromeric interactions or accessory proteins under normal expression conditions. |
Two-step purification of PMP70 protein complex from mouse liver to apparent homogeneity; preparative immunoprecipitation of ALDP complex; both analyzed by protein identification |
Biochimica et biophysica acta |
Medium |
15276650
|
| 2002 |
ATP binding and hydrolysis by PMP70 induce conformational changes in the protein specifically at the boundary between the transmembrane and nucleotide-binding domains, and in the helical domain between the Walker A and B motifs. MgATP or MgADP stabilizes a C-terminal 30-kDa fragment, while MgATP-γS protects the entire protein. The 30-kDa fragment forms a ~60 kDa complex consistent with PMP70 existing as a dimer on peroxisomal membranes. |
Limited trypsin digestion of rat liver peroxisomes pre-incubated with various nucleotides, followed by immunoblot analysis |
Biochemical and biophysical research communications |
Medium |
11883951
|
| 2005 |
Pex19p acts as a co-translational chaperone for PMP70 (ABCD3), binding it during translation to maintain solubility and proper conformation required for peroxisomal targeting. Two binding regions were identified: the N-terminal 61 amino acids and the region around TMD6. Deletion of either region prevented peroxisomal localization of GFP-PMP70 fusion proteins in CHO cells. |
In vitro translation system with purified Pex19p, co-immunoprecipitation, truncation/deletion constructs, GFP-fusion localization in CHO cells |
Biochimica et biophysica acta |
Medium |
16344115
|
| 2001 |
Efficient peroxisomal targeting of human PMP70 requires three targeting elements in the amino-terminal region: amino acids 61–80 (cytosolic loop), the first transmembrane domain, and the second transmembrane domain. PEX19 interactions are not required for targeting human PMP70 to peroxisomes and does not specifically bind the targeting elements. |
Truncation constructs and localization studies in cells; PEX19 interaction assays |
Biochemical and biophysical research communications |
Medium |
11453642
|
| 2009 |
The N-terminal 80-amino-acid segment of PMP70 is critical for suppressing an intrinsic ER-targeting function of TM1, enabling correct peroxisomal localization. Without the N80 segment, the full-length PMP70 localizes to the ER. The N80 segment alone targets to the outer mitochondrial membrane; combined with TM1-TM2, targeting is exclusively peroxisomal. Multiple organelle-targeting signals cooperate for correct peroxisomal membrane targeting. |
EGFP fusion constructs with N-terminal deletions expressed in COS cells; subcellular localization by fluorescence microscopy |
Journal of biochemistry |
Medium |
20007743
|
| 2015 |
A short 9-residue N-terminal motif in PMP70 (including Ser5 as indispensable) suppresses co-translational ER targeting by the TM1 signal sequence. Ser5Ala point mutation causes PMP70 to localize predominantly to the ER. The motif acts through binding 50-kDa and 20-kDa cytosolic proteins (crosslinking identified), functioning as an ER-targeting suppressor. |
Point mutagenesis (Ser5Ala), chimeric constructs with secretory signal peptide, protein crosslinking, subcellular localization by fluorescence microscopy |
Journal of biochemistry |
Medium |
26711236
|
| 1998 |
Overexpression of PMP70 (ABCD3) suppresses the peroxisome assembly defect caused by PEX2 mutations in CHO cells, restoring peroxisomal biogenesis (as measured by catalase latency, catalase localization, and VLCFA beta-oxidation). A mutant allele of PMP70 identified in a Zellweger syndrome patient failed to rescue, suggesting a functional interaction between PEX2 and PMP70 in the peroxisomal membrane. |
Expression of PMP70 in PEX2-deficient CHO cell clones; catalase latency assay, immunohistochemical localization of catalase, VLCFA beta-oxidation measurement |
European journal of cell biology |
Medium |
9765053
|
| 2025 |
The VCP-FAF2 complex (homolog of p97-UBXD8) prevents excessive pexophagy by regulating the accumulation of ubiquitinated ABCD3 on peroxisomal membranes. Loss of FAF2 leads to increased ubiquitination of ABCD3 and consequent autophagic degradation of peroxisomes. |
Quantitative proteomics, ubiquitination assays, autophagy rescue experiments, depletion of VCP/FAF2 |
Autophagy |
Medium |
39929145
|
| 2024 |
The p97-UBXD8 complex maintains peroxisome abundance by suppressing pexophagy. Loss of UBXD8 or inhibition of p97 increases ubiquitination of PMP70 (ABCD3) on peroxisomal membranes, triggering autophagic peroxisome degradation that can be rescued by depleting key autophagy proteins or overexpressing the deubiquitylase USP30. |
Quantitative proteomics, UBXD8/p97 depletion, ubiquitination assays, rescue by autophagy protein depletion and USP30 overexpression |
bioRxivpreprint |
Medium |
bio_10.1101_2024.09.24.614749
|
| 2008 |
Knockdown of PMP70 (ABCD3) in rat C6 glial cells impairs peroxisomal beta-oxidation and causes oxidative stress (increased nitric oxide, superoxide, and lipid peroxidation products) and production of pro-inflammatory cytokines (TNFα, IFNγ, IL-12). The oxidative stress was shown to be downstream of IL-12 release rather than a direct consequence of PMP70 loss. |
Stable RNAi knockdown cell line (abcd3kd), measurement of oxidative stress markers, antioxidant enzyme activities, cytokine quantification, neutralizing antibody against IL-12 |
Neurochemistry international |
Medium |
18992293
|
| 2021 |
ABCD3 interacts with INTS7 (integrator complex subunit 7) in mouse bone marrow mesenchymal stem cells, and this interaction suppresses oxidative stress (ROS and γ-H2AX accumulation). Knockdown of either INTS7 or ABCD3 impairs BM-MSC proliferation, induces apoptosis, decreases osteoblastic differentiation, and accelerates adipogenic differentiation. |
Co-immunoprecipitation (INTS7-ABCD3 interaction), RNAi knockdown of INTS7 and ABCD3, ROS measurement, differentiation assays (Alizarin Red S, Oil Red O staining) |
Frontiers in physiology |
Low |
34880777
|
| 1992 |
NEGATIVE FINDING: The major Mg2+-ATPases induced in rat liver peroxisomes by clofibrate are not associated with PMP70 (ABCD3), as demonstrated by proteinase K sensitivity differences, failure of co-immunoprecipitation, different behavior on native PAGE, and separation by gel filtration chromatography. |
Proteinase K protection assay, immunoprecipitation, native PAGE, gel filtration chromatography from rat liver peroxisomes |
Journal of biochemistry |
Medium |
1295880
|