FIGURE 2.

Thiol oxidoreductase activity is required for expression of all catalytically active AChE molecules. 6-Day-old QMCs were DFP-treated (A and B) or not (C and D) to inhibit all AChE molecules and allowed to recover for 1.5 h in the absence (A and C) or presence (B and D) of 1 mm bacitracin. The AChE forms were fractionated by velocity sedimentation in 5–20% sucrose gradients. G1, G2, and G4 refer to AChE monomers, dimers, and tetramers, and A4, A8, and A12 refer to the various collagen-tailed forms consisting of one, two, or three tetramers attached to the ColQ subunit, respectively. A12 refers to the ColQ-AChE form. When cell-associated thiol oxidoreductase activity was blocked, the intracellular levels of all newly synthesized catalytically active AChE forms decreased, including the ColQ-AChE. NT, not treated with DFP.