A1CF explained

APOBEC1 complementation factor is a protein that in humans is encoded by the A1CF gene.^{[1] [2] [3]}

Gene

Alternative splicing occurs at this locus and three full-length transcript variants, encoding three distinct isoforms, have been described. Additional splicing has been observed but the full-length nature of these variants has not been determined.^[3]

Function

Mammalian apolipoprotein B mRNA undergoes site-specific C to U deamination, which is mediated by a multi-component enzyme complex containing a minimal core composed of APOBEC1 and a complementation factor encoded by this gene.^[4] The gene product has three non-identical RNA recognition motifs and belongs to the hnRNP R family of RNA-binding proteins. It has been proposed that this complementation factor functions as an RNA-binding subunit and docks APOBEC1 to deaminate the upstream cytidine. Studies suggest that the protein may also be involved in other RNA editing or RNA processing events.^[3]

Its deletion results in lethality in mice.^[5]

Interactions

A1CF has been shown to interact with APOBEC1,^[6] CUGBP2,^[7] and SYNCRIP.^{[8] [9]}

Further reading

• Mehta A, Kinter MT, Sherman NE, Driscoll DM . Molecular cloning of apobec-1 complementation factor, a novel RNA-binding protein involved in the editing of apolipoprotein B mRNA . Mol. Cell. Biol. . 20 . 5 . 1846–54 . 2000 . 10669759 . 85365 . 10.1128/MCB.20.5.1846-1854.2000 .
• Lellek H, Kirsten R, Diehl I, Apostel F, Buck F, Greeve J . Purification and molecular cloning of a novel essential component of the apolipoprotein B mRNA editing enzyme-complex . J. Biol. Chem. . 275 . 26 . 19848–56 . 2000 . 10781591 . 10.1074/jbc.M001786200 . free .
• Yang Y, Sowden MP, Smith HC . Induction of cytidine to uridine editing on cytoplasmic apolipoprotein B mRNA by overexpressing APOBEC-1 . J. Biol. Chem. . 275 . 30 . 22663–9 . 2000 . 10833526 . 10.1074/jbc.M910406199 . free .
• Blanc V, Navaratnam N, Henderson JO, Anant S, Kennedy S, Jarmuz A, Scott J, Davidson NO . Identification of GRY-RBP as an apolipoprotein B RNA-binding protein that interacts with both apobec-1 and apobec-1 complementation factor to modulate C to U editing . J. Biol. Chem. . 276 . 13 . 10272–83 . 2001 . 11134005 . 10.1074/jbc.M006435200 . free .
• Harrington JJ, Sherf B, Rundlett S, Jackson PD, Perry R, Cain S, Leventhal C, Thornton M, Ramachandran R, Whittington J, Lerner L, Costanzo D, McElligott K, Boozer S, Mays R, Smith E, Veloso N, Klika A, Hess J, Cothren K, Lo K, Offenbacher J, Danzig J, Ducar M . Creation of genome-wide protein expression libraries using random activation of gene expression . Nat. Biotechnol. . 19 . 5 . 440–5 . 2001 . 11329013 . 10.1038/88107 . 25064683 .
• Lau PP, Chang BH, Chan L . Two-hybrid cloning identifies an RNA-binding protein, GRY-RBP, as a component of apobec-1 editosome . Biochem. Biophys. Res. Commun. . 282 . 4 . 977–83 . 2001 . 11352648 . 10.1006/bbrc.2001.4679 .
• Blanc V, Henderson JO, Kennedy S, Davidson NO . Mutagenesis of apobec-1 complementation factor reveals distinct domains that modulate RNA binding, protein-protein interaction with apobec-1, and complementation of C to U RNA-editing activity . J. Biol. Chem. . 276 . 49 . 46386–93 . 2001 . 11571303 . 10.1074/jbc.M107654200 . free .
• Anant S, Henderson JO, Mukhopadhyay D, Navaratnam N, Kennedy S, Min J, Davidson NO . Novel role for RNA-binding protein CUGBP2 in mammalian RNA editing. CUGBP2 modulates C to U editing of apolipoprotein B mRNA by interacting with apobec-1 and ACF, the apobec-1 complementation factor . J. Biol. Chem. . 276 . 50 . 47338–51 . 2001 . 11577082 . 10.1074/jbc.M104911200 . free .
• Henderson JO, Blanc V, Davidson NO . Isolation, characterization and developmental regulation of the human apobec-1 complementation factor (ACF) gene . Biochim. Biophys. Acta . 1522 . 1 . 22–30 . 2001 . 11718896 . 10.1016/S0167-4781(01)00295-0 .
• Xu XR, Huang J, Xu ZG, Qian BZ, Zhu ZD, Yan Q, Cai T, Zhang X, Xiao HS, Qu J, Liu F, Huang QH, Cheng ZH, Li NG, Du JJ, Hu W, Shen KT, Lu G, Fu G, Zhong M, Xu SH, Gu WY, Huang W, Zhao XT, Hu GX, Gu JR, Chen Z, Han ZG . Insight into hepatocellular carcinogenesis at transcriptome level by comparing gene expression profiles of hepatocellular carcinoma with those of corresponding noncancerous liver . Proc. Natl. Acad. Sci. U.S.A. . 98 . 26 . 15089–94 . 2001 . 11752456 . 64988 . 10.1073/pnas.241522398 . 2001PNAS...9815089X . free .
• Mehta A, Driscoll DM . Identification of domains in apobec-1 complementation factor required for RNA binding and apolipoprotein-B mRNA editing . RNA . 8 . 1 . 69–82 . 2002 . 11871661 . 1370230 . 10.1017/S1355838202015649 .
• Chester A, Somasekaram A, Tzimina M, Jarmuz A, Gisbourne J, O'Keefe R, Scott J, Navaratnam N . The apolipoprotein B mRNA editing complex performs a multifunctional cycle and suppresses nonsense-mediated decay . EMBO J. . 22 . 15 . 3971–82 . 2003 . 12881431 . 169042 . 10.1093/emboj/cdg369 .
• Blanc V, Kennedy S, Davidson NO . A novel nuclear localization signal in the auxiliary domain of apobec-1 complementation factor regulates nucleocytoplasmic import and shuttling . J. Biol. Chem. . 278 . 42 . 41198–204 . 2003 . 12896982 . 10.1074/jbc.M302951200 . free .
• Xie K, Sowden MP, Dance GS, Torelli AT, Smith HC, Wedekind JE . The structure of a yeast RNA-editing deaminase provides insight into the fold and function of activation-induced deaminase and APOBEC-1 . Proc. Natl. Acad. Sci. U.S.A. . 101 . 21 . 8114–9 . 2004 . 15148397 . 419566 . 10.1073/pnas.0400493101 . 2004PNAS..101.8114X . free .

Notes and References

1. Dance GS, Sowden MP, Cartegni L, Cooper E, Krainer AR, Smith HC . Two proteins essential for apolipoprotein B mRNA editing are expressed from a single gene through alternative splicing . J. Biol. Chem. . 277 . 15 . 12703–9 . April 2002 . 11815617 . 10.1074/jbc.M111337200 . free .
2. Chester A, Scott J, Anant S, Navaratnam N . RNA editing: cytidine to uridine conversion in apolipoprotein B mRNA . Biochim. Biophys. Acta . 1494 . 1–2 . 1–13 . December 2000 . 11072063 . 10.1016/S0167-4781(00)00219-0 .
3. Web site: Entrez Gene: A1CF APOBEC1 complementation factor.
4. Henderson JO, Blanc V, Davidson NO . Isolation, characterization and developmental regulation of the human apobec-1 complementation factor (ACF) gene . Biochim. Biophys. Acta . 1522 . 1 . 22–30 . November 2001 . 11718896 . 10.1016/S0167-4781(01)00295-0 .
5. Blanc V, Henderson JO, Newberry EP, Kennedy S, Luo J, Davidson NO . Targeted deletion of the murine apobec-1 complementation factor (acf) gene results in embryonic lethality . Mol. Cell. Biol. . 25 . 16 . 7260–9 . August 2005 . 16055734 . 1190267 . 10.1128/MCB.25.16.7260-7269.2005 .
6. Mehta A, Kinter MT, Sherman NE, Driscoll DM . Molecular cloning of apobec-1 complementation factor, a novel RNA-binding protein involved in the editing of apolipoprotein B mRNA . Mol. Cell. Biol. . 20 . 5 . 1846–54 . March 2000 . 10669759 . 85365 . 10.1128/MCB.20.5.1846-1854.2000 .
7. Anant S, Henderson JO, Mukhopadhyay D, Navaratnam N, Kennedy S, Min J, Davidson NO . Novel role for RNA-binding protein CUGBP2 in mammalian RNA editing. CUGBP2 modulates C to U editing of apolipoprotein B mRNA by interacting with apobec-1 and ACF, the apobec-1 complementation factor . J. Biol. Chem. . 276 . 50 . 47338–51 . December 2001 . 11577082 . 10.1074/jbc.M104911200 . free .
8. Lau PP, Chang BH, Chan L . Two-hybrid cloning identifies an RNA-binding protein, GRY-RBP, as a component of apobec-1 editosome . Biochem. Biophys. Res. Commun. . 282 . 4 . 977–83 . April 2001 . 11352648 . 10.1006/bbrc.2001.4679 .
9. Blanc V, Navaratnam N, Henderson JO, Anant S, Kennedy S, Jarmuz A, Scott J, Davidson NO . Identification of GRY-RBP as an apolipoprotein B RNA-binding protein that interacts with both apobec-1 and apobec-1 complementation factor to modulate C to U editing . J. Biol. Chem. . 276 . 13 . 10272–83 . March 2001 . 11134005 . 10.1074/jbc.M006435200 . free .