Figure 10.

Kinetic model of BFA-induced Golgi disassembly in semi-intact CHO-GT cells. (A) Successive reaction model. In this model, intact Golgi was transformed to tubular Golgi with the rate constant k₁ and then to fused Golgi with the rate constant k₂. Simple linear first-order kinetics through a series of three states of Golgi morphology without a reverse reaction is assumed. Rate constants, obtained from the Golgi tubule formation and Golgi tubule fusion assays, are shown, and those obtained from the Golgi disassembly assay are in parentheses. (B) Concurrent reaction model. In this model, intact Golgi disassembles through two concurrent pathways. One is the successive pathway described in A. The other is a direct pathway in which intact Golgi directly fuses to the ER with the rate constant k₃. Kinetic analysis of the plots from the Golgi disassembly assay (Figure 9, A and B) was preferentially adapted to the successive model.