Fig. 5: S1P protects PLM neurons intergenerationally.
From: An intestinal sphingolipid confers intergenerational neuroprotection
a, Chemical structure of S1P. b, Continuous exposure (P0 L4 larva to F1 adult) to 20 µM S1P reduces PLM axon breaks in mec-17(ok2109); lon-2(e678) animals. c, PLM axon breaks were reduced in mec-17(ok2109); lon-2(e678) animals when P0 mothers (L4 to young adult), but not F1 larvae, were exposed to S1P for 16 h. d, Experimental scheme for the intergenerational inheritance experiment. P0 animals (L4 larvae) were treated with methanol (control) or S1P for 16 h. Animals of each generation were allowed to lay eggs on untreated plates for 3 h and 3-d-old adults were assessed for axon breaks. e, The progeny of P0 mothers (mec-17(ok2109); lon-2(e678) animals) exposed to S1P for 16 h (L4 to young adult) had reduced PLM axon breaks for two generations (F1 and F2). f, S1P–fluorescein was detected in the oocytes of wild-type adult hermaphrodites after 16 h of feeding. A vehicle-treated control (left) and an animal following S1P–fluorescein treatment (right) are shown. Nomarski micrographs (top) and fluorescence images (bottom) of the same animals are provided. The dashed white lines outline oocytes. Lateral view, anterior to the left. Scale bar, 25 μm. g, RNAi-mediated knockdown of rme-2 suppresses S1P-induced reduction of PLM axon breaks in mec-17(ok2109); lon-2(e678) animals. b,c,e,g, n = 73, 73, 78, 74, 76 and 79 (b); n = 105, 104, 135 and 107 (c); n = 158, 163, 153, 157, 157 and 155 (e); and n = 104, 105, 107 and 104 (g) hermaphrodite animals per condition (left to right). P values were determined using an ANOVA (c,g) or unpaired Student’s t-test (b,e). ***P ≤ 0.001; **P ≤ 0.01; *P ≤ 0.05; and NS, not significant. Error bars indicate the s.e.m. Source data are provided.
