Figure 3:

LION-term enrichment and membrane fluidity of CHO K1 cells. CHO K1 cells were incubated overnight with PAL, LIN, or ARA (100 μM) (A) or with ARA (250 μM) (B–D). All incubations were performed in triplicate. For control (CON) incubations, cells were incubated with fatty acid free–BSA. (A, D) After extraction and lipidomics profiling by LC-MS/MS, enrichment analyses of the conditions of interest vs control incubations were performed by LION/web of (A) LION-terms indicating the presence of selected fatty acids or (D) LION-terms indicating the degree of membrane fluidity. Dot sizes in the dot plots are scaled to the number of associated lipids; colors are scaled to the level of enrichment (–log q-values). (B, C) After incubation, fluorescence emission spectra of lysates containing pyrenedecanoic acid (PDA) were measured (B). Fluorescence spectra examples of either control (black) or ARA-stimulated lysates (red). Gray shades indicate monomer and excimer fluorescence filters. (C) Mean ratios (bar) and individual data points (dots) of excimer over monomer fluorescence (representative data of 3 independent experiments). Statistical significance was determined by Welch's 2-tailed t-test. (A, C, D) Asterisk indicates P or q < 0.05, double asterisk P or q < 0.01, and triple asterisk P or q < 0.001. FDR: false-discovery rate.