Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10971679 | Developmental & Comparative Immunology | 2010 | 5 Pages |
Abstract
The avian IgY antibody isotype shares a common ancestor with both mammalian IgG and IgE and so provides a means to study the evolution of their structural and functional specialisations. Although both IgG and IgE bind to their leukocyte Fc receptors with 1:1 stoichiometry, IgY binds to CHIR-AB1, a receptor expressed in avian monocytes, with 2:1 stoichiometry. The mutagenesis data reported here explain the structural basis for this difference, mapping the CHIR-AB1 binding site to the CÏ
3/CÏ
4 interface and not the N-terminal region of CÏ
3 where, at equivalent locations, the IgG and IgE leukocyte Fc receptor binding sites lie. This finding, together with the phylogenetic relationship of the antibodies and their receptors, indicates that a substantial shift in the nature of Fc receptor binding occurred during the evolution of mammalian IgG and IgE.
Related Topics
Life Sciences
Biochemistry, Genetics and Molecular Biology
Developmental Biology
Authors
Alexander I. Taylor, Brian J. Sutton, Rosaleen A. Calvert,