Figure 1

Cholesterol metabolism in COS-7 cells. (A) RT-PCR analyses of P450scc and StAR in COS-7 cells. Total RNA was extracted and reverse-transcribed with (+) or without (−) reverse transcriptase (RTase), followed by PCR amplification. (B) HPLC analysis of cholesterol metabolites in COS-7 cells. COS-7 cells were incubated with [3H]cholesterol and then each extract was analyzed using HPLC. The arrowheads indicate the elution positions of standard steroids, cholesterol, and pregnenolone. (C) Identified steroid biosynthetic pathways in COS-7 cells. Black font indicates confirmed steroidogenic enzymes or pathways. Gray font indicates steroidogenic enzymes or pathways that were not confirmed. Similar results were obtained in repeated experiments using three different samples.