High impact information on Aox3

• Rodents are characterized by four aldehyde oxidases as follows: AOX1 and aldehyde oxidase homologs 1-3 (AOH1, AOH2, and AOH3) [1].
• The enzyme possesses aldehyde oxidase activity and oxidizes, albeit with low efficiency, exogenous substrates that are recognized by AOH1 and AOX1 [2].
• The AOH3 cDNA is characterized by remarkable similarity to AOX1, AOH1, AOH2, and xanthine oxidoreductase cDNAs [2].
• However, relative to CD-1 animals, an over 2 log reduction in the steady-state levels of liver AOH1 mRNA, protein, and enzymatic activity is observed in basal conditions and following administration of testosterone [3].
• The AOH1 and AOH2 genes are 98 and 60 kilobases long, respectively, and consist of 35 coding exons [4].

Biological context of Aox3

• The AOH1 gene has the potential to transcribe an extra leader non-coding exon, which is located downstream of exon 26, and is transcribed in the opposite orientation relative to all the other exons [4].
• Purification of the aldehyde oxidase homolog 1 (AOH1) protein and cloning of the AOH1 and aldehyde oxidase homolog 2 (AOH2) genes. Identification of a novel molybdo-flavoprotein gene cluster on mouse chromosome 1 [4].
• The selective cell and tissue distribution of AOH1 and AOH2 mRNAs is consistent with the localization of the respective protein products [5].
• Transfection of the AOH1 and AOH2 cDNAs results in the production of proteins with phenanthridine but not hypoxanthine oxidizing activity [5].
• AOH1 and AOH2 contain consensus sequences for a molybdopterin-binding site and two distinct 2Fe-2S redox centers [5].

Anatomical context of Aox3

• The AOH1 transcript is expressed in the hepatocytes of the adult and fetal liver and in spermatogonia [5].

Associations of Aox3 with chemical compounds

• Furthermore, the AOH1 protein has benzaldehyde oxidizing activity with electrophoretic characteristics identical to those of a previously identified aldehyde oxidase isoenzyme (Holmes, R. S. (1979) Biochem. Genet. 17, 517-528) [5].
• Employing an aldehyde oxidase specific substrate, AOX1/AOH1 activity was shown to be induced by dioxin in mouse liver [6].
• This activity was inhibited by a known inhibitor of aldehyde oxidases, and eliminated by including tungstate in the mouse diet, which is known to lead to inactivation of molybdoflavoenzymes, thus confirming that the enzymatic activity was attributable to AOX1/AOH1 [6].

Other interactions of Aox3

• In addition, we have cloned the cDNAs coding for rat AOH1 and AOH2, demonstrating that this animal species has the same complement of molybdo-flavoproteins as the mouse [2].

References