B-Arrestin

Arecaidine propargyl esther, 131 Arecoline, 131, 153 Amdt-Schulz law, 3 B-Arrestin, 84 Assays... 

To be ready for the next odor stimulus, jS-adrenoceptor kinase (Bark) 2 inactivates a receptor only a tenth of a second after the first stimulation occurred. This kinase phosphorylates the activated receptor, which allows another protein, B-arrestin, to bind to the receptor and inactivate it. This is a specific example of a group of enzymes that deactivate hormone or neuroreceptors (Dawson et al., 1993). 

Phosphorylation of these receptors enhances their affinity for B-arrestins upon binding of a 3-arrestin molecule, the capacity of the receptor to activate G proteins is blunted, presumably due to steric hindrance (see Figure 2-12). Arrestins constitute another large family of widely expressed... 

Fig. 5.7 (A) Arrestin binds to the phosphorylated receptor and deactivates the receptor. (B) Arrestin recruits clathrin to the receptor-arrestin complex and promotes receptor internalization through clathrin-coated pits. Clathrin is like the deck of an aircraft carrier, forming a platform where the receptor-arrestin complex can land . After landing , the receptor-arrestin complex Is transported by the carrier to its destination in the cell. Moreover, arrestin recruits the cytosolic c-Src tyrosine kinase to the arrestin-receptorcomplex and links receptor desensitization to the activation of the MAP kinase signalling pathway. (According to Zuker and Ranganthan. Reproduced with permission of the authors and Science.)...

M.G. Caron. A broader role for B-Arrestins. Sciensce, STKE 2003. 

Cheng ZJ, Zhao J, Sun Y, Hu W, Wu YL, Cen B, Wu GX, Pei G (2000) Beta-arrestin differentially regulates the chemokine receptor CXCR4-mediated signaling and receptor internalization, and this implicates multiple interaction sites between beta-arrestin and CXCR4. J Biol Chem 275 2479-2485... 

Bertrand, L., Parent, S., Caron, M., Legault, M., Joly, E., Angers, S., Bouvier, M., Brown, B., Houle, B., and Menard, L. (2002). The BRET2/arrestin assay in stable recombinant cells A platform to screen for compounds that interact with G protein-coupled receptors (GPCRs)./ Recept. Signal Transduct. Res. 22, 533-541. 

Figure 11-5. The model of arrestin and rhodopsin complex 1 2. A. One arrestin molecule bound to rhodopsin dimer. B. Two arrestin molecules bound to two adjacent rhodopsin dimers. View from cytoplasmic side...

J. Granzin, U. Wilden, Hui-Woog Choe, J. Labahn, B. KrafJt, and G. Biildt. X-ray crystal structure of arrestin from bovine rod outer segments. Nature, 391, 918-921, 1998. 

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