Apolipoprotein B mRNA editing enzyme, catalytic polypeptide 1 (APOBEC1)

Apolipoprotein B mRNA editing enzyme, catalytic polypeptide 1 (APOBEC1) is an RNA-specific cytidine deaminase that catalyzes the conversion of cytosine to uracil in apolipoprotein B (ApoB) mRNA, resulting in the introduction of a premature stop codon and subsequent production of ApoB48 rather than the full-length ApoB100 protein[1][2]. This C-to-U editing alters lipoprotein production and plays a central role in lipid metabolism, particularly in the intestine in humans. APOBEC1 functions as part of a multi-protein holoenzyme with cofactors (notably A1CF), and its expression and activity are tightly regulated to prevent genomic instability, as excessive or mislocalized activity can lead to off-target mutations in cellular DNA, contributing to cancer development and other pathologies[1][3]. APOBEC1 also contributes to innate immunity by editing viral genomes (e.g., reducing HIV or HBV replication), but its principal risk is its potential to induce somatic mutations that drive tumor development, making its expression level and activity a potential biomarker and therapeutic consideration in oncology and infectious disease[1][2].

Other names

C->U-editing enzyme APOBEC-1APOBEC1APO1BEDPCDAR1HEPRmRNA(cytosine(6666)) deaminase 1apolipoprotein B mRNA-editing enzyme 1apolipoprotein B mRNA editing enzyme complex-1apolipoprotein B mRNA editing enzyme, catalytic subunit 1

Deamination of cytosine to uracil on RNA (specifically apolipoprotein B mRNA), causing C-to-U editing and introduction of premature stop codons; Direct antiviral activity via deamination-induced mutagenesis in viral DNA/RNA