Localisation studies of transfected wildtype (WT) and skin disease associated mutant R42P Connexin 31 in keratinocytes. Green fluorescence indicates the EGFP fusion connexin protein. Red fluorescence shows either ß-actin or keratin filaments. Note conspicuous aggregation of wildtype Cx31 at the plasma membrane between the cells. In contrast, the majority of the mutant R42P-Cx31/EGFP protein was cytoplasmic with less apparent membrane localisation.