IUBMB Enzyme Nomenclature


Accepted name: mRNA(cytosine6666) deaminase

Reaction: cytosine6666 in apolipoprotein B mRNA + H2O = uracil6666 in apolipoprotein B mRNA + NH3

Other name(s): APOBEC-1 (catalytic component of an RNA-editing complex); APOBEC1 (catalytic subunit); apolipoprotein B mRNA-editing enzyme 1 (catalytic component of an RNA-editing complex); apoB mRNA-editing enzyme catalytic polypeptide 1 (catalytic component of an RNA-editing complex); apoB mRNA editing complex; apolipoprotein B mRNA editing enzyme; REPR

Systematic name: mRNA(cytosine6666) aminohydrolase

Comments: The apolipoprotein B mRNA editing enzyme complex catalyses the editing of apolipoprotein B mRNA at cytidine6666 to uridine, thereby transforming the codon for glutamine-2153 to a termination codon. Editing results in translation of a truncated apolipoprotein B isoform (apoB-48) with distinct functions in lipid transport. The catalytic component (APOBEC-1) contains zinc at the active site [3].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Chester, A., Weinreb, V., Carter, C.W., Jr. and Navaratnam, N. Optimization of apolipoprotein B mRNA editing by APOBEC1 apoenzyme and the role of its auxiliary factor, ACF. RNA 10 (2004) 1399-1411. [PMID: 15273326]

2. Fujino, T., Navaratnam, N., Jarmuz, A., von Haeseler, A. and Scott, J. C-→U editing of apolipoprotein B mRNA in marsupials: identification and characterisation of APOBEC-1 from the American opossum Monodelphus domestica. Nucleic Acids Res. 27 (1999) 2662-2671. [PMID: 10373583]

3. Barnes, C. and Smith, H.C. Apolipoprotein B mRNA editing in vitro is a zinc-dependent process. Biochem. Biophys. Res. Commun. 197 (1993) 1410-1414. [PMID: 8280158]

4. Chester, A., Somasekaram, A., Tzimina, M., Jarmuz, A., Gisbourne, J., O'Keefe, R., Scott, J. and Navaratnam, N. The apolipoprotein B mRNA editing complex performs a multifunctional cycle and suppresses nonsense-mediated decay. EMBO J. 22 (2003) 3971-3982. [PMID: 12881431]

[EC created 2013]

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