The surface receptor for immunoglobulin E (IgE) on rat basophilic leukemia cells and their normal counterparts has been postulated to consist of four polypeptide chains: a 45-kDa α-chain which binds IgE, a 33-kDa β-component and two disulfide-linked, 9-10-kDa γ-polypeptides. The instability of this complex in mild detergents makes it possible that, in vivo also, the structure may not be stable and that there is an independent assembly or exchange of the chains. We studied this question using surface-labeling and biosynthetic labeling techniques and found that the chains turn over coordinately and do not independently exchange. The results provide further support for the proposal that the αβγ2 complex is the unit receptor for IgE.
ASJC Scopus subject areas
- Molecular Biology