Integrin receptor complex

Gudz, T. I., Schneider, T. E., Haas, T. A. et al. Myelin proteolipid protein forms a complex with integrins and may participate in integrin receptor signaling in oligodendrocytes. /. Neurosci. 22,7398-7407, 2002. 

Integrin receptor-binding peptides have been used to enhance liposome binding, uptake, and expression (25,47 9). The inclusion of an 0(5pi integrin-targeted peptide into a liposomal complex enhanced transfection efficiency four- to five-fold in Jurkat cells and 10- to 13-fold in TF-1 cells (48). Confocal and electron microscopy revealed that the mechanism of cell entry conferred by RGD peptides on liposomes is predominantly by clathrin-coated endocytosis rather than by phagocytosis (50). 

Bohuslav J, Horejsi V, Hansmann C, Stockl J, Weidle UH, Majdic O, et al. Urokinase plasminogen activator receptor, beta 2-integrins, and Src-kinases within a single receptor complex of human monocytes. J Exp Med 1995 181(4) 1381—1390. 

Fig. 4.4 Integrins are transmembrane receptors. They are activated by components of the extracellular matnx, such as fibronectin and collagen. These interactions lead to clustering of integrin receptors and the formation of focal adhesions, intracellular cytoskeletal complexes, and formation of actin bundles.30 Activation of integrins is part of the celi-ceil adhesion process, integrins also bind to adhesion moiecules on adjacent celis.

CDllc member of b2 of integrin receptor family also called integrin alpha X, CR4, LeuM5. Clears opsonized par deles and immune complexes also binds to fibrinogen and is involved in adhesion of monocytes and neutrophils to endothelium. Myeloid cell marker. 

Adhesion molecules, proteins responsible for interactions between cells and their environment, especially, the extracellular matrix and other cells. Several different molecules act as cell adhesion receptors such as integrins, intercellular adhesion molecules (ICAM), leukocyte LFA-1, Mac-1 and pl50/95 molecules, the fibronectin receptor complex fibronectin), tenascin, and the position-specific (PS) antigens of Drosophila. 

The common feature of these adhesion-mediating sites is the presence of transmembrane integrin receptors forming an ECM-cytoskeleton nexus (see Sect. 5.3.1). In addition, many adapter proteins and signaling molecules congregate to build up a multiprotein complex at the cytoplasmic face of the cell membrane. 

In humans, iron is transported across the gut by a series of poorly defined processes. Fe(III), ferric ion, is absorbed via a J03 integrin and mobilferrin, whereas ferrous ion enter the cells via Nramp. Once inside the body, Fe(III) is transported through the serum by transferrin, a protein of molecular weight 63,000 Da. Fe(III) transferrin is recognized by a receptor protein on the cell surface. Via a process known as cell-mediated endocytosis, the Fe(III) transferrin/receptor complex induces the external cell membrane to pucker and eventually form a clatharin-coated vesicle in the cytoplasm. After removal of the clatharin, the vesicle (known as an endosome) becomes... 

FIGURE 34.1 Illustration of a focal adhesion complex. A cluster of transmembrane integrin receptor heterodimers is shown interacting with extracellular matrix proteins and cytoplasmic proteins vinculin, a-actinin, talin, and focal adhesion kinase (FAK). This complex interacts with the actin cytoskeleton. Adapted horn Petit, V. and Thiery, J.-P., Biol. Cell. 92, 477, 2000. With permission Yamada, K.M. and Miyamoto, S., Curr. Opin. Cell BioL 7, 681, 1995. With permission. 

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