Aconitase-1 (ACO1) Human Recombinant Protein

The protein encoded by this gene is a bifunctional, cytosolic protein that functions as an essential enzyme in the TCA cycle and interacts with mRNA to control the levels of iron inside cells. When cellular iron levels are high, this protein binds to a 4Fe-4S cluster and functions as an aconitase. Aconitases are iron-sulfur proteins that function to catalyze the conversion of citrate to isocitrate. When cellular iron levels are low, the protein binds to iron-responsive elements (IREs), which are stem-loop structures found in the 5' UTR of ferritin mRNA, and in the 3' UTR of transferrin receptor mRNA. When the protein binds to IRE, it results in repression of translation of ferritin mRNA, and inhibition of degradation of the otherwise rapidly degraded transferrin receptor mRNA. The encoded protein has been identified as a moonlighting protein based on its ability to perform mechanistically distinct functions. Alternative splicing results in multiple transcript variants [provided by RefSeq, Jan 2014]

IREB1: Iron sensor. Binds a 4Fe-4S cluster and functions as aconitase when cellular iron levels are high. Functions as mRNA binding protein that regulates uptake, sequestration and utilization of iron when cellular iron levels are low. Binds to iron-responsive elements (IRES) in target mRNA species when iron levels are low. Binding of a 4Fe-4S cluster precludes RNA binding. Belongs to the aconitase/IPM isomerase family.

Protein type: Translation; Carbohydrate Metabolism - glyoxylate and dicarboxylate; Lyase; Carbohydrate Metabolism - citrate (TCA) cycle; RNA-binding; EC 4.2.1.3; Endoplasmic reticulum

Chromosomal Location of Human Ortholog: 9p21.1

Cellular Component: Golgi apparatus; mitochondrion; endoplasmic reticulum; cytoplasm; cytosol

Molecular Function: protein binding; iron-responsive element binding; RNA binding; metal ion binding; 4 iron, 4 sulfur cluster binding; aconitate hydratase activity

Biological Process: regulation of translation; cellular iron ion homeostasis; tricarboxylic acid cycle; citrate metabolic process; response to iron(II) ion; intestinal absorption; post-embryonic development