ACO1 binds 4Fe-4S

Stable Identifier
Reaction [transition]
Homo sapiens
Locations in the PathwayBrowser
SVG |   | PPTX  | SBGN
Click the image above or here to open this reaction in the Pathway Browser
The layout of this reaction may differ from that in the pathway view due to the constraints in pathway layout
Iron and citrate are essential for the metabolism of most organisms so their regulation is critical for normal physiology and survival. Depending on cellular conditions, cytoplasmic aconitate hydratase (ACO1 aka iron regulatory protein 1, IRP1) can assume two different functions. During iron scarcity or oxidative stress, ACO1 functions as IRP1, binding to iron responsive elements (IREs) to modulate the translation of iron metabolism genes. In iron-rich conditions, IRP1 binds an iron-sulfur cluster (4Fe-4S) to function as a cytosolic aconitase. This functional duality of IRP1 connects the translational control of iron metabolising proteins to cellular iron levels.

Under iron-replete conditions, ACO1 binds the cofactor 4Fe-4S cluster and acts as an aconitase, isomerising citrate (CIT) to isocitrate (ISCIT) (Kaptain et al. 1991, Philpott et al. 1994, Dupuy et al. 2006).
Literature References
PubMed ID Title Journal Year
16407072 Crystal structure of human iron regulatory protein 1 as cytosolic aconitase

Fontecilla-Camps, JC, Darnault, C, Carpentier, P, Volbeda, A, Dupuy, J, Moulis, JM

Structure 2006
1946430 A regulated RNA binding protein also possesses aconitase activity

Haile, D, Downey, WE, Orloff, DG, Harford, JB, Philpott, C, Kaptain, S, Klausner, RD, Rouault, TA, Tang, C

Proc. Natl. Acad. Sci. U.S.A. 1991
8041788 The bifunctional iron-responsive element binding protein/cytosolic aconitase: the role of active-site residues in ligand binding and regulation

Philpott, CC, Klausner, RD, Rouault, TA

Proc. Natl. Acad. Sci. U.S.A. 1994
Catalyst Activity

iron-sulfur cluster binding activity of ACO1 [cytosol]

This event is regulated
Positively by
Orthologous Events
Cite Us!