Fig. 3. Strains lacking ARL1 accumulate [¹⁴C]-MA. PSY316 (ARL1; squares) and MA03 (arl1; circles) were incubated with [¹⁴C]-MA (2.5 µCi ml^–1, 2 mM final concentration) for up to 60 minutes. Cells were collected on nitrocellulose filters and washed three times with ice-cold 20 mM MgCl₂. Filters were counted by scintillation spectroscopy to determine the amount of internalized radioactivity. Data were collected in triplicate and are shown ±s.d. This experiment was repeated four times with similar results.