Figure 7.

Time course of content (A) and biosynthesis (B) of 4,4-dimethylsterols after administration of 3 μm Tb. Three-day-old TBY-2 cells were treated with 3 μm Tb for different periods of time and incubated with sodium [1-¹⁴C]acetate for 2 h before cell harvesting. A, Levels of the three major 4,4-dimethylsterols were quantified by GC (acetate derivatives) and expressed in micrograms per gram dry weight. B, Radioactivities incorporated into cycloartenol and 24-methylenecycloartanol were expressed as 10⁵ cpm g⁻¹ dry weight (dwt). 24-me cycloartanol, 24-Methylenecycloartanol.