Schematic representation of Cx43-protein sequence depicting the domains relevant for this study. Schematic illustration of the human Cx43 protein sequence (protein accession number used: P17302) using the Protter protein-visualization tool (http://wlab.ethz.ch/protter/start/; [37]), which represents one building block of the hexameric hemichannel. The four transmembrane domains are numbered. The cytoplasmic loop (CL), which harbors the L2 and Gap19 region, and the cytoplasmic tail (CT), which harbors the SH3-binding domain and the CT9 region, are indicated. Also, the amino acid regions that were deleted in Cx43 or Cx43-CT to generate full-length Cx43 mutants: Cx43ΔSH3, Cx43Δ19, Cx43ΔSH3Δ19 and Cx43-CT mutants: Cx43-CTΔSH3, Cx43-CTΔ19, Cx43ΔSH3Δ19 are indicated with colored lines