Diurnal transcriptome analysis of liver samples collected every 4 hours over 24 hours from SPF and GF WT and LKO male mice (n = 3/time point/group) maintained in 12:12 LD (ZT2, -6, -10, -14, -18, and -22). Reactome and KEGG pathways significantly enriched by oscillating transcripts within each group. A subset of pathways enriched in SPF WT oscillating genes (q < 0.05). A lack of bar indicates lack of significance for that group/pathway (q > 0.05). Pathways marked with red star are addressed in the text.