Project description:We examined the biological difference between H1299 cells with the treatments targeting circadian rhythm in order to better understand circadian rhythm disruption as a feature of cancer. To this end, we knocked down CLOCK using siRNA (siCLOCK) or melatonin pre-treatment and assessed the gene expression pattern by RNA-Seq.
Project description:Increased susceptibility of circadian clock mutant mice to metabolic diseases has led to the understanding that a molecular circadian clock is necessary for metabolic homeostasis. Circadian clock produces a daily rhythm in activity-rest and an associated rhythm in feeding-fasting. Feeding-fasting driven programs and cell autonomous circadian oscillator act synergistically in the liver to orchestrate daily rhythm in metabolism. However, an imposed feeding-fasting rhythm, as in time-restricted feeding, can drive some rhythm in liver gene expression in clock mutant mice. We tested if TRF alone, in the absence of a circadian clock in the liver or in the whole animal can prevent obesity and metabolic syndrome. Mice lacking the clock component Bmal1 in the liver, Rev-erb alpha/beta in the liver or cry1-/-;cry2-/- (CDKO) mice rapidly gain weight and show genotype specific increased susceptibility to dyslipidemia, hypercholesterolemia and glucose intolerance under ad lib fed condition. However, when the mice were fed the same diet under time-restricted feeding regimen that imposed 10 h feeding during the night, they were protected from weight gain and other metabolic diseases. Transcriptome and metabolome analyses of the liver from there mutant mice showed TRF reduces de novo lipogenesis, increased beta-oxidation independent of a circadian clock. TRF also enhanced cellular defense to metabolic stress. These results suggest a major function of the circadian clock in metabolic homeostasis is to sustain a daily rhythm in feeding and fasting. The feeding-fasting cycle orchestrates a balance between nutrient stress and cellular response to maintain homeostasis.
Project description:Sex differences in liver gene expression are dictated by sex-differences in circulating growth hormone (GH) profiles. Presently, the pituitary hormone dependence of mouse liver gene expression was investigated on a global scale to discover sex-specific early GH response genes that might contribute to sex-specific regulation of downstream GH targets and to ascertain whether intrinsic sex-differences characterize hepatic responses to plasma GH stimulation. RNA expression analysis using 41,000-feature microarrays revealed two distinct classes of sex-specific mouse liver genes: genes subject to positive regulation (class-I) and genes subject to negative regulation by pituitary hormones (class-II). Genes activated or repressed in hypophysectomized (Hypox) mouse liver within 30-90min of GH pulse treatment at a physiological dose were identified as direct targets of GH action (early response genes). Intrinsic sex-differences in the GH responsiveness of a subset of these early response genes were observed. Notably, 45 male-specific genes, including five encoding transcriptional regulators that may mediate downstream sex-specific transcriptional responses, were rapidly induced by GH (within 30min) in Hypox male but not Hypox female mouse liver. The early GH response genes were enriched in 29 male-specific targets of the transcription factor Mef2, whose activation in hepatic stellate cells is associated with liver fibrosis leading to hepatocellular carcinoma, a male-predominant disease. Thus, the rapid activation by GH pulses of certain sex-specific genes is modulated by intrinsic sex-specific factors, which may be associated with prior hormone exposure (epigenetic mechanisms) or genetic factors that are pituitary-independent, and could contribute to sex-differences in predisposition to liver cancer or other hepatic pathophysiologies.
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from Mus musculus tissues (Heart, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from seven Mus musculus tissues (Heart, Brain, Liver, Lung, Kidney, Skeletal Muscle, Thymus)