Immunoglobulin superfamily

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. 

Williams, A. F. and Barclay, A N. The immunoglobulin superfamily - domains for cell surface recognition. Annu. Rev. Immunol. 6 381-405,1988. 

Kelm, S., Pelz, A., Schauer, R. etal. Sialoadhesin, myelin-associated glycoprotein and CD22 define a new family of sialic acid-dependent adhesion molecules of the immunoglobulin superfamily. Curr. Biol. 4 965-972,1994. 

Walsh, F. S. and Doherty, P. Neural cell adhesion molecules of the immunoglobulin superfamily role in axon growth and guidance. Annu. Rev. Cell. Dev. Biol. 13 425-456, 1997. 

Table 3.3. General features of the immunoglobulin superfamily of adhesion molecules...

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. 

The adhesion proteins are divided into a number of different groups. The main groups are the integrins, cadherins, immunoglobulin superfamily group, selec-tins, and CD44. A brief description of each of these types of adhesion proteins now follows. 

Martin-Padura I, Lostaglio S, Schneemann M, Williams L, Romano M, Fruscella P, Panzeri C, Stoppacciaro A, Ruco L, Villa A, Simmons D, and Dejana E [1998] Junctional adhesion molecule, a novel member of the immunoglobulin superfamily that distributes at intercellular junctions and modulates monocyte transmigration. J Cell Biol 142 117-127... 

The TCR is a member of the immunoglobulin superfamily and is composed of an N-terminal immunoglobulin variable domain, an immunoglobulin constant... 

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