Fig. 3.

Amniote Cx26 hemichannels can be opened by CO₂. a Amniotes, amphibia and lungfish share the CO₂ carbamylation motif (highlighted boxes). b Images of dye loading in response to CO₂, and the zero Ca²⁺ positive control. c Summary data showing that reptile Cx26 hemichannels open to CO₂ but those of Xenopus and Lepidosiren do not (expressed as the change in pixel intensity from control 35 mmHg PCO₂). Mann Whitney test used in comparisons. Box and whisker plots: box, first and third quartiles; horizontal line, median; whiskers, the furthest point that lies no more than 1.5 times the interquartile range from the median. Each point is the median change in pixel intensity from an independent transfection. Scale bar 20 µm