Figure 8: Mammalian GABAB receptor can functionally substitute for worm GBB-1 in lifespan regulation.
From: Metabotropic GABA signalling modulates longevity in C. elegans
(a) Transgenic expression of rat GABAB receptors (rGB1 and rGB2) fully suppresses the long-lived phenotype of gbb-1 mutant worms (log-rank test, P=0.11, n=49ā66 for different genotypes). (b,c) Mammalian GABAB receptor antagonist CGP36216 (b) and SCH50911 (c) do not have a notable effect on lifespan in wild-type worms (log-rank test, P=0.389 and P=0.527, respectively. n=57ā127 for the different treatments). Drug concentration: 1āĪ¼M. (d,e) Mammalian GABAB receptor antagonist CGP36216 (d) and SCH50911 (e) extend the lifespan of transgenic worms expressing rat GABAB receptor (log-rank test, P<0.001 in the each case, n=44ā87 for the different case). Drug concentration: 1āĪ¼M antagonist. (f) Schematic model illustrating a genetic pathway through which GABA regulates longevity. The putative site-of-action of each gene (neuron versus intestine) is denoted. All lifespan assays were carried out at 20āĀ°C and were repeated at least twice with the exception of b,c. Please see Supplementary Table 1 for detailed statistical analysis of lifespan data.
