Fig. 6: Glug does not mediate glucose transfer to MB neurons for LTM.
From: Glycolysis-derived alanine from glia fuels neuronal mitochondria for memory in Drosophila
a, The FRET glucose sensor FLII12Pglu-700μδ670 was expressed in adult cortex glia. The two images show the CFP and YFP channels. The dashed lines delimit the cortex glia region where the glucose FRET signal was quantified. Scale bar, 50 µm. b, Nicotine stimulation (50 µM, 30 s) increased glucose concentration in cortex glia. KD of glug in adult cortex glia had no effect on the nicotine-induced glucose elevation (n = 14, t26 = 0.99, P = 0.33). c, The FRET glucose sensor FLII12Pglu-700μδ6 was expressed in adult MB neurons. The two images show the CFP and YFP channels. The dashed lines delimit MB neuron somata where the glucose FRET signal was quantified. Scale bar, 30 µm (Supplementary Video 2). d, The glucose concentration in MB neuron somata following the application of validamycin A (4 mM, dashed line) decreased faster in flies after spaced training as compared to flies conditioned with a non-associative spaced unpaired training protocol (n = 12, t22 = 3.56, P = 0.002). When glug was knocked down in adult cortex glia, spaced training continued to elicit a faster decrease of glucose concentration in MB neurons compared to unpaired controls (n = 12, t22 = 3.52, P = 0.002). All data are presented as mean ± s.e.m. Asterisks (**P < 0.01; NS, not significant, P > 0.05) illustrate the significance level of a two-sided t-test.
