ASIC1 oligomeric states resolved by SDS-PAGE after crosslinking with BMOE.

A: Anti-Anti-His-tag western blot of the surface-biotinylated protein fractions from either non-injected oocytes (n.i.), or oocytes expressing either the His₈-tagged form of ASIC1a-ΔC_Ct (ΔC_Ct), lacking cysteines in the C-terminus, or the corresponding cysteine-substitution mutants V74C-ΔC_Ct, Y426C-ΔC_Ct, G430C-ΔC_Ct, and G433C-ΔC_Ct. Crosslinking with 2 mM BMOE was performed at the cell surface; the cell-surface biotinylated proteins were affinity-purified on streptavidin beads. Numbers I to IV, designate the four most prominent bands. B: Apparent Mw values of the ASIC1 oligomers (kDa, mean ±SD) estimated for each of the four main bands (I to IV) for the different constructs, as in A. Lines represents linear regression of the average values, with slopes ranging from 71 ± 4.2 to 73.8 ± 4.6 kDa for the different ASIC1a cDNA constructs.