Figure 2. Diurnal Rhythms of Gut Microbiome Phyla in Mice from Different Feeding Conditions.

(A) Pie chart showing the percentage of cycling and non-cycling OTUs (across all conditions) in NA mice (n = 18).

(B) Upper double-plot line graph – where the second cycle is a duplicate of the first cycle following the dashed line – shows the average percent read (± SEM) of the three most predominant phyla at each time point (n = 3 per time point). Black and white boxes indicate light off and light on, respectively. The yellow box shows when mice had access to food. Colored asterisks at the end of lines in line graph show which phyla were cycling based on JTK analysis (that is ADJ.P < 0.05 and BH.Q. < 0.05). Since it takes > 1 hour for a food bolus to reach the cecum (Padmanabhan et al., 2013), lower bar graphs show the average percent reads (± SEM, n = 9) for the dark/active feeding phase (ZT 17, 21, and 1), and the light/inactive fasting phase (ZT 5, 9, and 13). *p < 0.05.

(C) The top ten OTUs (based on percent reads) are depicted in a polar plot. The radian indicates the phase of the OTU’s peak, the distance from center is the average percent read across all time points, and the radius of each point indicates the amplitude of cycling. The colors of the circles indicate the phylum of the OTU: Firmicutes (pink), Bacteroidetes (blue), and Verrucomicrobia (green). The black arc on the left side of the plot indicates the light/dark cycle. The yellow arc depicts access to food. The bottom polar plot shows a magnified view of the inner ring (10%) of the top polar plot.

These descriptions also apply to panels for FA mice (D, E, F) and FT mice (G, H, I).