Basal laminas integrin

Plakin proteins link intracellular keratin intermediate filaments to hemidesmosomes of basal epidermal cells, or to desmosomes on suprabasal epidermal cells (Sect. 5.2.1), whereas type XVII collagen (the only collagen secreted by epithelial cells ) and integrins attach hemidesmosomes to a basal lamina. Three p 1 integrins (with al, a3 or a5 partners)... 

In epithelial cells, integrin a6(34 is concentrated in hemidesmosomes and plays a major role in adhering cells to matrix in the underlying basal lamina, as discussed in detail in Section 6.3. Some integrins, particularly those expressed by certain blood cells, participate in heterophillc cell-cell interactions. The members of this large family play important roles in adhesion and signaling in both epithelial and nonepithelial tissues. 

Cell-surface adhesion receptors (e.g., a6p4 integrin in hemidesmosomes) anchor cells to the basal lamina, which in turn is connected to other ECM components (see Figure 6-1). 

Ninety percent of cancer deaths are caused by metastatic rather than primary tumors. Define metastasis. Explain the rationale for the following new cancer treatments (a) batima-stat, an inhibitor of matrix metalloproteinases and of the plasminogen activator receptor, (b) antibodies that block the function of integrins, integral membrane proteins that mediate attachment of cells to the basal laminae and extracellular matrices of various tissues, and (c) bisphosphonate, which inhibits the function of bone-digesting osteoclasts. 

After type IV collagen, laminin is the most abundant protein in basal laminae. Laminin provides additional structural support for the tissues through its ability to bind to type IV collagen, to other molecules present in the ECM, and to cell surface-associated proteins (the integrins, see section D). 

The basal lamina surrounding the abluminal surface of the endothelial cell is composed of type IV collagen, heparan sulfate, fibronectin, and laminin. Laminin acts as a charge barrier and interacts with integrins to regulate permeability of the BBB and cellular transport across it [5]. 

Laminin Laminins are trimeric proteins that contain an a-chain, a P-chain, and a y-chain, found in five, four, and three genetic variants Basal lamina of endothelial cells Interacts with integrins to regulate permeability/cellular transport Rabbit anti-laminin. Sigma, St. Louis, MO... 

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