Figure 8
Schematic presentation of an intra-membrane cross talk between wt Sx1A or Sx1A single mutants with the α1 subunit of VGCC.
(a) Interaction between the calcium channel and Sx1A occurs through the SH group of TM Cys271 and Cys272 (for simplicity only two Sx1A molecules and a single channel are shown). (b) Mutating or oxidizing the Cys residues disrupts the transmembrane interaction between Sx1A and the channel yielding ‘inefficient’ contact with the channel and affects evoked release. The cytosolic Sx1A/channel interaction is not affected by the redox state of the Sx1A TM domain cysteines.
