Au RNA Binding Protein/Enoyl-Coa Hydratase (AUH) Human Recombinant Protein

The methylglutaconyl-CoA hydratase, mitochondrial 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, May 2010]

AUH: Catalyzes the conversion of 3-methylglutaconyl-CoA to 3- hydroxy-3-methylglutaryl-CoA. Has very low enoyl-CoA hydratase activity. Was originally identified as RNA-binding protein that binds in vitro to clustered 5'-AUUUA-3' motifs. Defects in AUH are the cause of 3-methylglutaconic aciduria type 1 (MGA1). MGA1 is 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. MGA1 can be distinguished from other forms of MGA 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 MGA forms). Belongs to the enoyl-CoA hydratase/isomerase family. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: Amino Acid Metabolism - valine, leucine and isoleucine degradation; EC 4.2.1.18; Mitochondrial; Lyase; RNA-binding

Chromosomal Location of Human Ortholog: 9q22.31

Cellular Component: mitochondrion; mitochondrial matrix

Molecular Function: methylglutaconyl-CoA hydratase activity; mRNA 3'-UTR binding; enoyl-CoA hydratase activity

Biological Process: leucine catabolic process; branched chain family amino acid catabolic process

Disease: 3-methylglutaconic Aciduria, Type I