The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

The lymphoma transmembrane glycoprotein GP85 (CD44) is a novel guanine nucleotide-binding protein which regulates GP85 (CD44)-ankyrin interaction.

In this study, we have used photoaffinity labeling by [32P]azido-GTP as well as [32P]ADP-ribosylation by pertussis toxin (PT) and cholera toxin (CT) to identify GTP-binding proteins associated with mouse T-lymphoma plasma membranes. Our results indicate that GP85 (CD44) can be photoaffinity labeled by [32P] azido-GTP and [32P]ADP-ribosylated by both PT and CT. Using purified GP85 (CD44) obtained by Triton X-100 extraction, wheat germ agglutinin-Sepharose, and anti-GP85 (CD44) antibody affinity chromatographies, we have further characterized GP85 (CD44) as a GTP-binding protein. GP85 (CD44) is found to bind guanosine 5'-3-O-(thio)triphosphate (GTP gamma S) in a time- and dose-dependent manner with a dissociation constant of 0.83 nM. Importantly, GP85 (CD44) appears to display a GTPase activity which hydrolyzes [gamma-32P]GTP at a rate of 0.011 mol of Pi released/ mol of GP85 (CD44)/min. This GTPase activity can be readily inhibited by PT- or CT-mediated ribosylation of GP85 (CD44). Most interestingly, GTP binding significantly enhances the interaction of purified GP85 (CD44) with ankyrin, whereas ADP-ribosylation of GP85 (CD44) by PT or CT inhibits the GTP- induced increase in ankyrin binding to GP85 (CD44). In addition to GP85 (CD44) being the first reported transmembrane GTP-binding protein, these results suggest that GTP plays an important role in promoting the interaction between GP85 (CD44) and its underlying membrane cytoskeleton through ankyrin.[1]


WikiGenes - Universities