Regulation of postprandial gene expression by glucocorticoid and insulin signaling.

(A) Blood glucose and corticosterone, insulin and NEFA levels in serum from mice injected preprandial with dex and/or S961. Data are presented as mean ± SEM (n = 4). Statistical significance is calculated using Student t test. (B) Relative expression of genes (repressed in ZT14-fed animals compared to ZT10-unfed animals) in livers isolated from animals injected preprandial with vehicle, dex, S961, and dex + S961 (average FC of RPKM, n = 4). Relative expression is calculated for fed versus unfed animals (vehicle injected) and fed animals injected with vehicle versus fed animals injected with S961, dex, and dex + S961, respectively. Data are plotted for gene repressed from the ZT10 to ZT14-fed (Q1–Q5) characterized in Fig 1. (C) Differential expression of feeding-repressed genes regulated by dex, S961, and dex + S961 injection. Three hundred sixty-nine feeding-repressed genes were identified from ZT14-unfed versus fed vehicle injected animals at FDR n = 4). Differential expression of these feeding-regulated genes was subsequently visualized from fed animals injected preprandial with vehicle, dex, S961, and dex + S961 injections. FDR is indicated for individual feeding-repressed genes for which black represents FDR > 0.2 (n = 4 in each treatment group). (D) Principle component analysis (log2 RPKM) of feeding-regulated genes (identified at FDR n = 4). Cluster 1 represents feeding-repressed genes not regulated by dex and S961. (F, G, and H) Examples of genes in clusters 2, 3, 4, and 5. RPKM is presented as mean ± SEM (n = 4). Statistical significance is calculated using Student t test, *p p p p > 0.05. (I) Enrichment of genes in clusters 1–5 regulated by liver-specific disruption of GR (L-GRKO). Differentially expressed genes in L-GRKO were identified at FDR n = 4), and enrichment of these GR regulated genes in clusters 1–5 was subsequently evaluated relative to randomly selected feeding-regulated genes. (J) Enrichment of genes in clusters 1–5 regulated by liver-specific disruption of IRS1/2 (L-IRSdKO). Differentially expressed genes in L-IRSdKO were identified at FDR n = 4), and enrichment of these insulin receptor-regulated genes in clusters 1–5 was subsequently evaluated relative to 100 randomly selected feeding-regulated genes. Numerical values for panels A–J are available in S6 Data. dex, dexamethasone; FC, fold change; FDR, false discovery rate; GR, glucocorticoid receptor; IRS1, Insulin Receptor Substrate 1; L-IRSdKO, liver specific insulin receptor substrate knockout; L-GRKO, liver specific GR knockout; NEFA, nonesterified fatty acid; RPKM, reads per kilo base per million mapped reads; ZT, Zeitgeber time