Cloning and sequence of the cDNA coding for rat type II Fc gamma receptor of mast cells.

A clone encoding the rat type II Fc gamma receptor was isolated from a cDNA library of the rat mucosal mast cell line RBL-2H3 and its sequence determined. The predicted amino acid sequence is highly homologous with the mouse type II as well as rat type III Fc gamma receptors. The site of alternative splicing which generates the mouse Fc gamma Rb2 isoform is completely conserved. Hence we consider the new sequence to encode a rat Fc gamma RII b2 isoform. In further analogy to the mouse receptor, no consensus motif known to be involved in accessory chain association was observed in the transmembranal domain. The importance of the identification of this receptor for investigation of the immunological stimulation of mast cells is discussed.