Molecular cloning and sequencing of the cDNA encoding the feline FcγRIIIA (CD16) homologue

We amplified the cDNA encoding the feline FcγRIIIA (CD16) homologue from peripheral blood mononuclear cells by polymerase chain reaction and cloned two forms of FCGR3A cDNA. Sequencing analysis revealed that the open reading frame of feline FCGR3A cDNA consists of 750 or 747 base pairs encoding 250 or 249 amino acid residues, respectively. Comparison of the predicted amino acid sequence of feline FCGR3A cDNA with those of other mammalians’ homologues revealed that the extracellular domain has a relatively low homology. However, the cytoplasmic domain contained an 8-amino acid motif, Leu-Phe-Val-Val-Asp-Thr-Gly-Leu, which was considered to interact with an accessory molecule such as the γ chain of Fc receptors for IgE to form heterodimeric complexes.