Palmitoylation of AKAP79 on cysteine 36 and 129 allows its association with lipid rafts. A, HEK-293 cells stably expressing AKAP79-YFP wild type and the triple mutant (C36S,C62S,C129S ((C36,62,129S))) were homogenized with 0.5% Triton X-100. Soluble (Sol) and insoluble extracts were isolated, and the insoluble extracts were loaded on a density gradient. The light fractions 2 and 3 (lipid rafts) and the high density fractions 4 and 5 (HD) were pooled and centrifuged to precipitate proteins. The gradient fractions, pellets (resuspended in lysis buffer), and soluble and total homogenates were analyzed by Western blot. B, densitometry analysis of blots corrected against loading control and expressed as the ratio of immunoreactivity of mutant over wild type (Wt). Data are presented as means ± S.E. for at least four independent experiments, **, p < 0.01. C, confocal imaging of cells expressing AKAP79-YFP wild type, triple (C36S,C62S,C129S (C36,62,129S)), or double (C36S,C129S (C36,129S)) mutants. Scale bars, 20 μm.