Distribution of ABCA1, ABCG1, and ABCG4 between Triton X-100 raft and non-raft domains. HEK293, HEK/ABCA1, HEK/ABCG1, HEK/ABCG1-KM, or HEK/ABCG4 cells (A) or SH-SY5Y cells (B) treated with TO901317 and 9-cis retinoic acid for 24 h were incubated with buffer containing 1% Triton X-100 on ice. The cell lysates were separated by OptiPrep-gradient ultracentrifugation. Ten fractions of each were separated by 5–20% polyacrylamide gel electrophoresis, and ABCA1, ABCG1, ABCG4, caveolin-1, paxillin, FAK, or flotillin was detected by immunoblotting. 