FIG. 3.

Triton X-100 extraction efficiently strips envelope cholesterol from VLP-Pr55^gag. VLPs were collected from SFV-C/HIVgag-infected Jurkat cells that had been metabolically labeled with [³⁵S]methionine or [³H]cholesterol. VLPs were extracted with 1% Triton X-100 at 0°C, and the extracts were fractionated on iodixanol step gradients. Aliquots of gradient fractions were analyzed by SDS-PAGE ([³⁵S]methionine-labeled VLPs) or by scintillation counting ([³H]cholesterol-labeled VLPs). Labeled Pr55^gag and [³H]cholesterol in gradient fractions are expressed as percentages of the total (sum of all fractions).