Allergic reactions are triggered via crosslinking of the high-affinity receptor for immunoglobulin E, FcεRI. In humans, FcεRI is expressed as a tetramer (αβγ 2 ) and a trimer (αγ 2 ). The β subunit is an amplifier of FcεRI surface expression and signaling. Here, we show that as a consequence of alternative splicing, the FcεRIβ gene encodes two proteins with opposing and competing functions. One isoform is the full-length classical β, the other a novel truncated form, β T . In contrast to β, β T prevents FcεRI surface expression by inhibiting α chain maturation. Moreover, β T competes with β to control FcεRI surface expression in vitro. We propose that the relative abundance of the products of the β gene may control the level of FcεRI surface expression and thereby influence susceptibility to allergic diseases.
Donnadieu, E., Jouvin, M. H., Rana, S., Moffatt, M. F., Mockford, E. H., Cookson, W. O., & Kinet, J. P. (2003). Competing functions encoded in the allergy-associated FcεRIβ gene. Immunity, 18(5), 665–674. https://doi.org/10.1016/S1074-7613(03)00115-8