Immunoglobulin superfamily receptors

Fig. 3.1 Families of cytokine receptors the cytokine receptors are classified into five major families immunoglobulin superfamily receptors, type I cytokine receptors, type II cytokine receptors, TNF-like receptors and chemokine receptors. The drawings illustrate their general biochemical structure (see Color Insert)...

Brummendorf, T, and V. Lemmon. 2001. Immunoglobulin superfamily receptors cis-interactions, intracellular adapters and alternative splicing regulate adhesion. Curr. Opin. Cell Biol. 13 611-618. 

C, which is found in complement proteins FI, F2, and F3, first found in fibronectin I, the immunoglobulin superfamily domain N, found in some growth factor receptors E, a module homologous to the calcium-binding E-F hand domain and LB, a lectin module found in some cell surface proteins. (Adapted from Baron, M., Norman, D., and Campbell, I., 1991, Protein modnles. Trends in Biochemical Sciences 16 13—1 7.)... 

Recombinant DNA technology has also facilitated detailed study of cytokine receptors. Based upon amino acid sequence homology, receptors are usually classified as belonging to one of six known superfamilies (Table 8.3). Individual members of any one superfamily characteristically display 20-50 per cent homology. Conserved amino acids normally occur in discrete bands or clusters, which usually correspond to a discrete domain in the receptor. Most receptors exhibit multiple domains. In some cases a single receptor may contain domains characteristic of two or more superfamilies. For example, the IL-6 receptor contains domains characteristic of both the haematopoietic and immunoglobulin superfamilies, making it a member of both. 

The cell surface additionally displays receptors responsible for cell-cell recognition [28]. Members of this class of receptors are selectins [29] that recognize specific carbohydrates from other cells in the presence of calcium. Other cell surface receptors belong to the immunoglobulin superfamily (IgSF) [30] that promote calcium-independent cell-cell adhesion. The third important class are the calcium-dependent cell adhesion molecules, the cadherins [31], which form dimers with cadherin molecules presented on the surfaces of other cells and hence promote aggregation of similar cell types. 

Bucciarelli LG, Wendt T, Rong L, Lalla E, Hofmann MA, Goova MT, Taguchi A, Yan SF, Yan SD, Stern DM, Schmidt AM. 2002. RAGE is a multiligand receptor of the immunoglobulin superfamily implications for homeostasis and chronic disease. Cell Mol Life Sci 59(7) 111 7—1128. 

Colonna, M. (1997). Immunoglobulin superfamily inhibitory receptors From natural killer cells to antigen-presenting cells. Res. Immunol. 148(3), 169-171. 

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