Extended Data Fig. 7: Vagal neurons are contacted by Pyy-labeled cells and are activated by intracolonic stimuli.

(a) List of significantly enriched gene ontology terms related to neuronal connection in Pyy-labeled cells (n = 6 mice; adjusted *P < 0.05 by topGO analysis). (b) Table of base mean, fold change, and adjusted P value for pre-synaptic genes between PyyGFP cells and non-GFP cells (DESeq2 with two-tailed t-tests). (c) Quantification of contacts between Pyy-labeled cells and Pgp9.5 neuronal fibers in different regions of the intestine (n = 3 mice). (d) Schematic of the vagal recording technique. The cervical vagus was recorded while the entire colon was simultaneously perfused with stimulus. (e) (Left) Schematic demonstrating 473 nm light via an intracolonic light emitting diode (LED) activating the cation channel Channelrhodopsin (ChR2) and depolarizing a Pyy-labeled cell. (Right) Representative image showing expression of ChR2-tdTomato (red) in a colonic Pyy-labeled cell (green). (f) Spike raster from vagal recordings in which PBS, 2 μg/mL flagellin, or 7% intralipid was perfused into the colon, representative of n = 4 mice. Gray bar represents the perfusion interval. (g) (Left) Vagal responses to intracolonic perfusion of PBS or 7% intralipid in wild-type mice (n = 4 mice). Error bars indicate S.E.M. (Right) Quantification of peak response to intralipid (*P < 0.05 by two-tailed paired t-test). (h) (Left) Schematic demonstrating 532 nm light activating the anion channel Halorhodopsin (Halo) and hyperpolarizing a Pyy-labeled cell. (Right) Representative image showing expression of Halorhodopsin-YFP (Green) in a colonic Pyy-labeled cell (red). Scale bars=10μm. Graphics in d,e,h adapted from ref. ³, AAAS.