AUH

AU-specific RNA-binding enoyl-CoA hydratase (AUH) protein binds to the AU-rich element (ARE), a common element found in the 3' UTR of rapidly decaying mRNA such as c-fos, c-myc and granulocyte/ macrophage colony stimulating factor. ARE elements are involved in directing RNA to rapid degradation and deadenylation. AUH is also homologous to enol-CoA hydratase, an enzyme involved in fatty acid degradation, and has been shown to have intrinsic hydratase enzymatic activity. AUH is thus a bifunctional chimera between RNA binding and metabolic enzyme activity. A possible subcellular localization in the mitochondria has been demonstrated for the mouse homolog of this protein which shares 92% identity with the human protein. It has been suggested that AUH may have a novel role as a mitochondrial located AU-binding protein. Human AUH is expressed as a single mRNA species of 1.8 kb, and translated as a 40-kDa precursor protein which is subsequently processed to a 32-kDa mature form. [provided by RefSeq]

Full Name

AU RNA binding protein/enoyl-Coenzyme A hydratase

Function

Catalyzes the conversion of 3-methylglutaconyl-CoA to 3-hydroxy-3-methylglutaryl-CoA (PubMed:11738050, PubMed:12434311, PubMed:12655555).
Also has itaconyl-CoA hydratase activity by converting itaconyl-CoA into citramalyl-CoA in the C5-dicarboxylate catabolism pathway (PubMed:29056341).
The C5-dicarboxylate catabolism pathway is required to detoxify itaconate, a vitamin B12-poisoning metabolite (PubMed:29056341).
Has very low enoyl-CoA hydratase activity (PubMed:7892223).
Was originally identified as RNA-binding protein that binds in vitro to clustered 5'-AUUUA-3' motifs (PubMed:7892223).

Biological Process

Branched-chain amino acid catabolic process Source: Reactome
Fatty acid beta-oxidation Source: GO_Central
Leucine catabolic process Source: UniProtKB-UniPathway

Cellular Location

Mitochondrion

Involvement in disease

3-methylglutaconic aciduria 1 (MGCA1): An inborn error of leucine metabolism. It leads to an autosomal recessive syndrome with variable clinical phenotype, ranging from delayed speech development to severe psychomotor retardation, coma, failure to thrive, metabolic acidosis and dystonia. MGCA1 can be distinguished from other forms of MGCA by the pattern of metabolite excretion: 3-methylglutaconic acid levels are higher than those detected in other forms, whereas methylglutaric acid levels are usually only slightly elevated and there is a high level of 3-hydroxyisovaleric acid excretion (not present in other MGCA forms).