Abstract by David Tripp
Chemistry and Biochemistry
Required Post-Translational Modifications of Capillary Morphogenesis Gene 2 for Co-Localization of ß-arrestin Upon Treatment of Anthrax Toxin
Capillary Morphogenesis Gene 2 (CMG2) is commonly known for its activity as an anthrax toxin receptor, internalizing CMG2 via endocytosis following binding of the anthrax protective antigen (PA) moiety of the binary toxin. ß-arrestin has been reported as being necessary for PA endocytosis, but the role it plays therein has yet to be completely understood. To investigate the role of CMG2 post-translational modifications on ß-arrestin recruitment after PA binding, our lab has generated fluorescent protein fusions of CMG2 mutants at the post-translational modification sites on its cytosolic tail. These mutants were individually transfected into HEK293T also expressing ß-arrestin-RFP. Since HEK293T cells do not natively express CMG2, we were able to systematically probe co-localization of CMG2 and ß-arrestin at the cell membrane and on endosomal membranes following PA treatment. We have identified important sites of post-translational modifications required to recruit ß-arrestin to CMG2 during endocytosis to begin to understand signaling pathways whereby CMG2 function.