Parent Class:

EC-Numbers → 3 -- Hydrolases → 3.5 -- Acting on carbon-nitrogen bonds, other than peptide bonds → 3.5.4 -- In cyclic amidines

Synonyms: 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

Unification Links: BRENDA:3.5.4.36, ENZYME:3.5.4.36, IUBMB-ExplorEnz:3.5.4.36

Reaction:
a cytosine⁶⁶⁶⁶ in apolipoprotein B mRNA + H⁺ + H₂O → a uracil⁶⁶⁶⁶ in apolipoprotein B mRNA + ammonium

Summary:
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 [Barnes93]

Citations: [Fujino99, Chester03, Chester04]

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References

Barnes93: Barnes C, Smith HC (1993). "Apolipoprotein B mRNA editing in vitro is a zinc-dependent process." Biochem Biophys Res Commun 197(3);1410-4. PMID: 8280158

Chester03: Chester A, Somasekaram A, Tzimina M, Jarmuz A, Gisbourne J, O'Keefe R, Scott J, Navaratnam N (2003). "The apolipoprotein B mRNA editing complex performs a multifunctional cycle and suppresses nonsense-mediated decay." EMBO J 22(15);3971-82. PMID: 12881431

Chester04: Chester A, Weinreb V, Carter CW, Navaratnam N (2004). "Optimization of apolipoprotein B mRNA editing by APOBEC1 apoenzyme and the role of its auxiliary factor, ACF." RNA 10(9);1399-411. PMID: 15273326

Fujino99: Fujino T, Navaratnam N, Jarmuz A, von Haeseler A, Scott J (1999). "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(13);2662-71. PMID: 10373583

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Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 46(D1):D633-D639 2018
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