Oligomerization of the N-terminally truncated torsinA variants. (A) Far-UV circular dichroism spectra of purified torsinAΔ40 (1 mg/ml, solid line) and the dialysis buffer (dotted line) are shown. (B) Gel-filtration analysis of torsinAΔ40 in the absence of nucleotides or in the presence of 2 mM ATP or ADP is shown. The elution times of molecular weight standards (kDa) are indicated. (C) BN-PAGE (upper panel) and SDS-PAGE (lower panel) analysis was followed by immunoblotting with anti-torsinA antibodies of lysates from HEK293 and CHO cells expressing either full-length torsinA (WT), torsinAΔ40 (Δ40), torsinAΔ40ΔE (Δ40ΔE) or untransfected cells (C). For BN-PAGE, the migration positions of the native-electrophoresis standards are indicated. The migration position of β-amylase (200 kDa) is indicated with an arrow. Protein migration in BN-PAGE can reflect other biophysical properties, besides the molecular weight, so the molecular weight determination is only approximate. The figure shows a representative result from two independent experiments.