Fig. 6.

Summary of mutagenesis data for P2X receptors in the region of the cysteine-rich finger. The arginine residues that serve as targets for ADP-ribosylation in mouse P2X7 [23], rat, and human P2X7 (our own unpublished observations) are highlighted in cyan. Conserved cysteine residues are highlighted in yellow. Amino acid residues that, when mutated, result in a gain-of-function are shown in bold and are highlighted in green [59, 60]. Residues that alter the sensitivity of the receptor to zinc, copper, and/or magnesium are shown in bold red [58, 59, 61, 77]. The positions of the cysteines (numbering for mouse P2X7) are indicated on top, the proposed connectivity [6] is indicated below. mm = Mus musculus, hs = Homo sapiens, rn = Rattus norvegicus, sm = Schistosoma mansoni, dd = Dictyostelium discoideum