C->U-editing enzyme APOBEC-4, also known as Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 4, is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the APOBEC4 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.

Function

This gene encodes a member of the AID / APOBEC

APOBEC

300px|thumb|upright|alt = Colored dice with checkered background|Example of a member of the APOBEC family, APOBEC-2. A cytidine deaminase from Homo Sapiens....

 family of polynucleotide (deoxy)cytidine deaminases, which convert cytidine

Cytidine

Cytidine is a nucleoside molecule that is formed when cytosine is attached to a ribose ring via a β-N1-glycosidic bond...

 to uridine

Uridine

Uridine is a molecule that is formed when uracil is attached to a ribose ring via a β-N1-glycosidic bond.If uracil is attached to a deoxyribose ring, it is known as a deoxyuridine....

. Other AID/APOBEC family members are involved in mRNA editing, somatic hypermutation and recombination of immunoglobulin genes, and innate immunity to retroviral infection.