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Updated: Aug 7, 2026

A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells
07:09

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Published on: July 31, 2012

Glycosyl-phosphatidylinositol linkage as a mechanism for cell-surface expression of immunoglobulin D

J Wienands1, M Reth

  • 1Max-Planck Institut für Immunbiologie, Freiburg, Germany.

Nature
|March 19, 1992
PubMed

The B-cell antigen receptor of the IgM and IgD class is a multimeric complex consisting of the membrane-bound form of the immunoglobulin molecule and two other proteins, Ig-alpha and Ig-beta. The Ig-alpha and Ig-beta proteins form a disulphide-linked alpha/beta heterodimer and are encoded by the mb-1 (ref 9, 10) and B29 genes, respectively. Surface expression of the membrane-bound IgM molecule requires assembly with the alpha/beta heterodimer. The IgD molecule, however, can be expressed on the cell surface in an alpha/beta-dependent and -independent form. We show here that in the alpha/beta-independent form the IgD molecule is anchored in the plasma membrane through a glycosyl-phosphatidylinositol linker. In the presence of the alpha/beta heterodimer, most of the otherwise glycosyl-phosphatidylinositol-linked IgD molecule is expressed on the cell surface as transmembrane proteins.

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