My. Nettleton et Jp. Kochan, ROLE OF GLYCOSYLATION SITES IN THE IGE FC MOLECULE, International archives of allergy and immunology, 107(1-3), 1995, pp. 328-329
The Fc region of immunoglobulin E (IgE) comprising the C(epsilon)3 and
C(epsilon)4 domains (residues 329-547) is sufficient for binding to t
he high-affinity IgE Fe receptor (Fc epsilon RI alpha). Three potentia
l N-linked glycosylation sites are present within the C(epsilon)3 doma
in. To determine the effect of the glycosylation sites on IgE Fe synth
esis and on Fc epsilon RI alpha binding, site-directed mutagenesis was
performed. Mutant IgE Fc constructs were expressed in COS cells and a
nalyzed for protein synthesis and secretion, and Fc epsilon RI alpha b
inding activity We find that only N-371 and N-394 are glycosylated, an
d that the residues surrounding the glycosylation site at N-394 are re
quired for Fc epsilon RI alpha binding activity.