Family With Sequence Similarity 19, Member A3 (FAM19A3)

FAM19A3 is a member of the TAFA family which is composed of five highly homologous genes that encode small secreted proteins. These proteins contain conserved cysteine residues at fixed positions, and are distantly related to MIP-1alpha, a member of the CC-chemokine family. The TAFA genes encode proteins of approximately 100 amino acids that contain conserved cysteine residues at fixed positions. TAFA-1 to -4 are more closely related to each other than to TAFA-5, in which a conserved motif including CC in TAFA-1 to -4 is not present. In H. sapiens, TAFA-3 has two isoforms formed by alternative splicing. Sequence homology analyses reveal that TAFA proteins appear distantly related to MIP-1alpha, a member of the CC-chemokine family. TAFA mRNAs are highly expressed in specific brain regions, with little expression seen in other tissues.