image:Apobec.J.Steinfeld.D.png, 300px, upExample of a member of the APOBEC family, APOBEC-2. A cytidine deaminase from ''Homo sapiens''.; ; rendered usin
PyMOL
APOBEC ("apolipoprotein B mRNA editing enzyme, catalytic polypeptide") is a family of evolutionarily conserved cytidine deaminases. A mechanism of generating protein diversity is messenger RNA, mRNA editing. Members of this family are RNA editing#C-U editing, C-to-U editing enzymes. The

N-terminal The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...

domain of APOBEC like proteins is the catalytic domain, while the C-terminal domain is a pseudocatalytic domain. More specifically, the catalytic domain is a zinc dependent cytidine deaminase domain and is essential for cytidine deamination. RNA editing by APOBEC-1 requires homodimerisation and this complex interacts with RNA binding proteins to form the editosome. In humans/mammals they help protect from viral infections. These enzymes, when misregulated, are a major source of mutation in numerous cancer types. A 2013 review discussed the structural and biophysical aspects of APOBEC3 family enzymes. Many of the APOBEC protein features are described in the widely studied APOBEC3G's page.

Family members

Human genes encoding members of the APOBEC protein family include: * APOBEC1 *

APOBEC2 Probable C->U-editing enzyme APOBEC-2 is a protein that in humans is encoded by the ''APOBEC2'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning '' ...

* APOBEC3A * APOBEC3B * APOBEC3C *

APOBEC3D Probable DNA dC->dU-editing enzyme APOBEC-3D is a protein that in humans is encoded by the ''APOBEC3D'' gene. This gene is a member of the cytidine deaminase gene family. It is one of seven related genes or pseudogenes found in a cluster, thought ...

APOBEC3E Probable DNA dC->dU-editing enzyme APOBEC-3D is a protein that in humans is encoded by the ''APOBEC3D'' gene. This gene is a member of the cytidine deaminase gene family. It is one of seven related genes or pseudogenes found in a cluster, thought ...

" now refers to this) *

APOBEC3F DNA dC->dU-editing enzyme APOBEC-3F is a protein that in humans is encoded by the ''APOBEC3F'' gene. This gene is a member of the cytidine deaminase gene family. It is one of seven related genes or pseudogenes found in a cluster, thought to resul ...

* APOBEC3G *

APOBEC3H DNA dC->dU-editing enzyme APOBEC-3H, also known as Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3H or APOBEC-related protein 10, is a protein that in humans is encoded by the ''APOBEC3H'' gene. Function This gene encodes a m ...

APOBEC4 C->U-editing enzyme APOBEC-4, also known as Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 4, is a protein that in humans is encoded by the ''APOBEC4'' gene. It is primarily expressed in testis and found in mammals, chicken, but ...

* Activation-induced (cytidine) deaminase (AID)

References

{{protein-stub EC 3.5.4