Fig. 3.

Cx26-D50A and Cx26-A88V hemichannels cause cell death that can be rescued by elevated extracellular Ca²⁺. Control, wild-type Cx26-, Cx26-D50A-, and Cx26-A88V-injected cells were incubated in the presence or absence of 4 mM extracellular calcium. H₂O (A)- and wild-type Cx26 (B)-injected cells survived in Ca²⁺ free media, while Cx26-A88V-injected cells displayed increased pigment disorganization and blebbing (C). Cx26-D50A-expressing oocytes also showed increased blebbing in the absence of calcium (D). Incubation of oocytes in 4 mM Ca²⁺ (E-H) dramatically improved the appearance of Cx26-D50A- and Cx26-A88V-injected cells. Quantification of the extent of oocyte death in modified Barth's medium without added Ca²⁺ (I) showed that 85% of Cx26-A88V- and 27% of Cx26-D50A-expressing oocytes died within 72 h (n = 26 oocytes/condition). Data are the means ± SE.