Cell adhesion molecules types

Fig. 4.6(a) Migration of LHRH neurocrine cells prenatal transportation along the track of extra-bulbar VN axons (caudal branch). CB, cribriform plate FB, forebrain cell types, TAG-1, transient axonal surface glycoprotein and N-CAM, neural cell adhesion molecule (from Yoshida et al, 1995). 

FIGURE 7-1 The immunoglobulin (Ig) gene family of molecules. Several varieties of Ig domain-containing molecules are contained within the Ig gene superfamily. Most are type I membrane proteins some have only Ig domains or other moieties that may convey function (see text). V, variable Ig domain C, constant Ig domain MAG, myelin-associated glycoprotein NCAM, neural cell adhesion molecule GPI, glycosylphosphatidyl-inositol EC, extracellular domain FN, fibronectin. 

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. 

AC VIII, adenylyl cyclase type VIII BDNF, brain-derived neurotrophic factor CamKII, calcium-calmodulin kinase II GIRK2, G protein-activated inward rectifying potassium 2 MAOA, monoamine oxidase A n.d., not determined NCAM, neural cell adhesion molecule nNOS, neuronal nitric oxide synthase Petl, ETS domain transcription factor tPA, serine protease tissue-plasminogen activator (tPA). t/ > Increase/decrease in anxiety-related behavior. No effect. 

From his examination of many different combinations of cell types, Steinberg deduced a hierarchy of adhesiveness and proposed that quantitative differences in adhesiveness could account for sorting out. More recently molecules that mediate cell adhesion have been identified and precise patterns of cell associations have been reproduced in mixed cell reaggregation systems with cells manipulated to express different cell adhesion molecules and with cells expressing different amounts of the same cell adhesion molecule (Takeichi, 1991 Steinberg and Takeichi, 1994). 

The contacts between two adjoining cell membranes are stabilized by specific cell adhesion molecules (CAMs), which include the Ca+2-dependent cadherins. These molecules appear to lead the way for cell-cell communications and are involved in mechanochemical transduction via cell-cell interactions. In some cell types, cadherins are concentrated within adherens junctions that are stretch-sensitive and their extracellular domains interact with cadherins on adjacent cells whereas their cytoplasmic domains provide attachment to the actin cytoskeleton via catenins and other cytoskeletal proteins. The Rho family is required for the establishment and maintenance of cadherin-based adherens junctions. The type of cadherin expressed in a cell can affect the specificity and the physiological properties of cell-cell interactions. 

Integrins are members of a laige family of transmembrane proteins that act as receptors for cell-adhesion molecules. Integrins are heteromeric proteins. The type of integrin expressed on the surface of a cell determines what kind of adhesion molecules and hence which cells can be bound. 

TDO TE TEC Teff TE TG TGE Thl Th2 TIA d yptophan 2,3-dioxygenase echo time thymic epithelial cell T effector cells d anscripdon factor digeminal ganglia d ansforming growth factor T helper type 1 cell T helper type 2 cell d ansient ischemic attack VI VAMP VCAM primary visual cortex vesicle-associated membrane protein vascular cell adhesion molecule... 

Sasaki H, Nishikata I, Shiraga T et al. Overexpression of a cell adhesion molecule, TSLCl, as a possible molecular marker for acute-type adult T-cell leukemia. Blood 2005 105(3) 1204-1213. 

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