ABSTRACT
Recombinant adeno-associated virus (rAAV) vectors have the unique property of being able to perform genomic targeted integration (TI) without inducing a double-strand break (DSB). In order to improve our understanding of the mechanism behind TI mediated by AAV and improve its efficiency, we performed an unbiased genetic screen in human cells using a promoterless AAV-homologous recombination (AAV-HR) vector system. We identified that the inhibition of the Fanconi anemia complementation group M (FANCM) protein enhanced AAV-HR-mediated TI efficiencies in different cultured human cells by â¼6- to 9-fold. The combined knockdown of the FANCM and two proteins also associated with the FANCM complex, RecQ-mediated genome instability 1 (RMI1) and Bloom DNA helicase (BLM) from the BLM-topoisomerase IIIα (TOP3A)-RMI (BTR) dissolvase complex (RMI1, having also been identified in our screen), led to the enhancement of AAV-HR-mediated TI up to â¼17 times. AAV-HR-mediated TI in the presence of a nuclease (CRISPR-Cas9) was also increased by â¼1.5- to 2-fold in FANCM and RMI1 knockout cells, respectively. Furthermore, knockdown of FANCM in human CD34+ hematopoietic stem and progenitor cells (HSPCs) increased AAV-HR-mediated TI by â¼3.5-fold. This study expands our knowledge on the mechanisms related to AAV-mediated TI, and it highlights new pathways that might be manipulated for future improvements in AAV-HR-mediated TI.
Subject(s)
CRISPR-Cas Systems , DNA Helicases/antagonists & inhibitors , DNA-Binding Proteins/antagonists & inhibitors , Dependovirus/genetics , Gene Editing , Hematopoietic Stem Cells/metabolism , RecQ Helicases/antagonists & inhibitors , DNA Helicases/genetics , DNA Helicases/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Genetic Vectors , HeLa Cells , Hematopoietic Stem Cells/cytology , Homologous Recombination , Humans , RecQ Helicases/genetics , RecQ Helicases/metabolismABSTRACT
UNLABELLED: Sterol regulatory element binding protein1c (SREBP1c) is a key transcription factor for de novo lipogenesis during the postprandial state. During nutritional deprivation, hepatic SREBP1c is rapidly suppressed by fasting signals to prevent lipogenic pathways. However, the molecular mechanisms that control SREBP1c turnover in response to fasting status are not thoroughly understood. To elucidate which factors are involved in the inactivation of SREBP1c, we attempted to identify SREBP1c-interacting proteins by mass spectrometry analysis. Since we observed that ring finger protein20 (RNF20) ubiquitin ligase was identified as one of SREBP1c-interacting proteins, we hypothesized that fasting signaling would promote SREBP1c degradation in an RNF20-dependent manner. In this work, we demonstrate that RNF20 physically interacts with SREBP1c, leading to degradation of SREBP1c via ubiquitination. In accordance with these findings, RNF20 represses the transcriptional activity of SREBP1c and turns off the expression of lipogenic genes that are targets of SREBP1c. In contrast, knockdown of RNF20 stimulates the expression of SREBP1c and lipogenic genes and induces lipogenic activity in primary hepatocytes. Furthermore, activation of protein kinase A (PKA) with glucagon or forskolin enhances the expression of RNF20 and potentiates the ubiquitination of SREBP1c via RNF20. In wild-type and db/db mice, adenoviral overexpression of RNF20 markedly suppresses FASN promoter activity and reduces the level of hepatic triglycerides, accompanied by a decrease in the hepatic lipogenic program. Here, we reveal that RNF20-induced SREBP1c ubiquitination down-regulates hepatic lipogenic activity upon PKA activation. CONCLUSION: RNF20 acts as a negative regulator of hepatic fatty acid metabolism through degradation of SREBP1c upon PKA activation. Knowledge regarding this process enhances our understanding of how SREBP1c is able to turn off hepatic lipid metabolism during nutritional deprivation.
Subject(s)
Cyclic AMP-Dependent Protein Kinases/physiology , Lipid Metabolism/physiology , Liver/chemistry , Liver/metabolism , Sterol Regulatory Element Binding Protein 1/metabolism , Ubiquitin-Protein Ligases/physiology , Animals , COS Cells , Chlorocebus aethiops , Fatty Liver/metabolism , Gene Expression Regulation , HeLa Cells , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Nutritional Status , Protein Stability , Sterol Regulatory Element Binding Protein 1/antagonists & inhibitorsABSTRACT
UNLABELLED: Recent evidence suggests that obese animals exhibit increased endoplasmic reticulum (ER) stress in the liver and adipose tissue. Although ER stress is closely associated with lipid homeostasis, it is largely unknown how ER stress contributes to hepatic steatosis. In this study, we demonstrate that the induction of ER stress stimulates hepatic steatosis through increased expression of the hepatic very low-density lipoprotein receptor (VLDLR). Among the unfolded protein response sensors, the protein kinase RNA-like ER kinase-activating transcription factor 4 signaling pathway was required for hepatic VLDLR up-regulation. In primary hepatocytes, ER stress-dependent VLDLR expression induced intracellular triglyceride accumulation in the presence of very low-density lipoprotein. Moreover, ER stress-dependent hepatic steatosis was diminished in the livers of VLDLR-deficient and apolipoprotein E-deficient mice compared with wild-type mice. In addition, the VLDLR-deficient mice exhibited decreased hepatic steatosis upon high-fat diet feeding. CONCLUSION: These data suggest that ER stress-dependent expression of hepatic VLDLR leads to hepatic steatosis by increasing lipoprotein delivery to the liver, which might be a novel mechanism explaining ER stress-induced hepatic steatosis.
Subject(s)
Endoplasmic Reticulum Stress/physiology , Fatty Liver/physiopathology , Receptors, LDL/physiology , Up-Regulation/physiology , Activating Transcription Factor 4/metabolism , Animals , Apolipoproteins E/deficiency , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Disease Models, Animal , Fatty Liver/metabolism , Lipoproteins/metabolism , Liver/metabolism , Mice , Mice, Knockout , Receptors, LDL/deficiency , Receptors, LDL/genetics , Triglycerides/metabolismABSTRACT
In this study, we demonstrate that activation of AMP-activated protein kinase (AMPK) with glabridin alleviates adiposity and hyperlipidemia in obesity. In several obese rodent models, glabridin decreased body weight and adiposity with a concomitant reduction in fat cell size. Further, glabridin ameliorated fatty liver and plasma levels of triglyceride and cholesterol. In accordance with these findings, glabridin suppressed the expression of lipogenic genes such as sterol regulatory element binding transcription factor (SREBP)-1c, fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl-CoA desaturase (SCD)-1 in white adipose tissues and liver, whereas it elevated the expression of fatty acid oxidation genes such as carnitine palmitoyl transferase (CPT)1, acyl-CoA oxidase (ACO), and peroxisome proliferator-activated receptor (PPAR)α in muscle. Moreover, glabridin enhanced phosphorylation of AMPK in muscle and liver and promoted fatty acid oxidation by modulating mitochondrial activity. Together, these data suggest that glabridin is a novel AMPK activator that would exert therapeutic effects in obesity-related metabolic disorders.
Subject(s)
AMP-Activated Protein Kinases/metabolism , Adiposity/drug effects , Isoflavones/pharmacology , Lipid Metabolism/drug effects , Obesity/drug therapy , Phenols/pharmacology , Animals , Body Weight/drug effects , Fatty Acids/metabolism , Mice , Mice, Inbred C57BL , Mitochondria/drug effects , Mitochondria/metabolism , Obesity/metabolism , Phosphorylation/drug effectsABSTRACT
Emerging evidence indicates that the accretion of senescent cells is linked to metabolic disorders. However, the underlying mechanisms and metabolic consequences of cellular senescence in obesity remain obscure. In this study, we found that obese adipocytes are senescence-susceptible cells accompanied with genome instability. Additionally, we discovered that SREBP1c may play a key role in genome stability and senescence in adipocytes by modulating DNA-damage responses. Unexpectedly, SREBP1c interacted with PARP1 and potentiated PARP1 activity during DNA repair, independent of its canonical lipogenic function. The genetic depletion of SREBP1c accelerated adipocyte senescence, leading to immune cell recruitment into obese adipose tissue. These deleterious effects provoked unhealthy adipose tissue remodeling and insulin resistance in obesity. In contrast, the elimination of senescent adipocytes alleviated adipose tissue inflammation and improved insulin resistance. These findings revealed distinctive roles of SREBP1c-PARP1 axis in the regulation of adipocyte senescence and will help decipher the metabolic significance of senescence in obesity.
Subject(s)
Insulin Resistance , Adipocytes/metabolism , Adipose Tissue/metabolism , Humans , Insulin Resistance/physiology , Obesity/metabolism , Poly (ADP-Ribose) Polymerase-1/genetics , Poly (ADP-Ribose) Polymerase-1/metabolism , Sterol Regulatory Element Binding Protein 1/genetics , Sterol Regulatory Element Binding Protein 1/metabolismABSTRACT
Homologous recombination (HR)-based gene therapy using adeno-associated viruses (AAV-HR) without nucleases has several advantages over classic gene therapy, especially the potential for permanent transgene expression. However, the low efficiency of AAV-HR remains a major limitation. Here, we tested a series of small-molecule compounds and found that ribonucleotide reductase (RNR) inhibitors substantially enhance AAV-HR efficiency in mouse and human liver cell lines approximately threefold. Short-term administration of the RNR inhibitor fludarabine increased the in vivo efficiency of both non-nuclease- and CRISPR/Cas9-mediated AAV-HR two- to sevenfold in the murine liver, without causing overt toxicity. Fludarabine administration induced transient DNA damage signaling in both proliferating and quiescent hepatocytes. Notably, the majority of AAV-HR events occurred in non-proliferating hepatocytes in both fludarabine-treated and control mice, suggesting that the induction of transient DNA repair signaling in non-dividing hepatocytes was responsible for enhancing AAV-HR efficiency in mice. These results suggest that use of a clinically approved RNR inhibitor can potentiate AAV-HR-based genome-editing therapeutics.
Subject(s)
CRISPR-Cas Systems , Genetic Vectors , Animals , CRISPR-Cas Systems/genetics , Dependovirus/genetics , Endonucleases/genetics , Gene Editing/methods , Homologous Recombination , Humans , Mice , Vidarabine/analogs & derivativesABSTRACT
Excessive hepatic glucose production (HGP) is a key factor promoting hyperglycemia in diabetes. Hepatic cryptochrome 1 (CRY1) plays an important role in maintaining glucose homeostasis by suppressing forkhead box O1 (FOXO1)-mediated HGP. Although downregulation of hepatic CRY1 appears to be associated with increased HGP, the mechanism(s) by which hepatic CRY1 dysregulation confers hyperglycemia in subjects with diabetes is largely unknown. In this study, we demonstrate that a reduction in hepatic CRY1 protein is stimulated by elevated E3 ligase F-box and leucine-rich repeat protein 3 (FBXL3)-dependent proteasomal degradation in diabetic mice. In addition, we found that GSK3ß-induced CRY1 phosphorylation potentiates FBXL3-dependent CRY1 degradation in the liver. Accordingly, in diabetic mice, GSK3ß inhibitors effectively decreased HGP by facilitating the effect of CRY1-mediated FOXO1 degradation on glucose metabolism. Collectively, these data suggest that tight regulation of hepatic CRY1 protein stability is crucial for maintaining systemic glucose homeostasis.
Subject(s)
Cryptochromes , Diabetes Mellitus, Experimental , Hyperglycemia , Animals , Cryptochromes/genetics , Cryptochromes/metabolism , Diabetes Mellitus, Experimental/metabolism , Forkhead Box Protein O1/genetics , Forkhead Box Protein O1/metabolism , Gluconeogenesis/physiology , Glucose/metabolism , Glucose/pharmacology , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Hyperglycemia/metabolism , Liver/metabolism , MiceABSTRACT
Lipid droplets (LDs) are key subcellular organelles for regulating lipid metabolism. Although several subcellular organelles participate in lipid metabolism, it remains elusive whether physical contacts between subcellular organelles and LDs might be involved in lipolysis upon nutritional deprivation. Here, we demonstrate that peroxisomes and peroxisomal protein PEX5 mediate fasting-induced lipolysis by stimulating adipose triglyceride lipase (ATGL) translocation onto LDs. During fasting, physical contacts between peroxisomes and LDs are increased by KIFC3-dependent movement of peroxisomes toward LDs, which facilitates spatial translocations of ATGL onto LDs. In addition, PEX5 could escort ATGL to contact points between peroxisomes and LDs in the presence of fasting cues. Moreover, in adipocyte-specific PEX5-knockout mice, the recruitment of ATGL onto LDs was defective and fasting-induced lipolysis is attenuated. Collectively, these data suggest that physical contacts between peroxisomes and LDs are required for spatiotemporal translocation of ATGL, which is escorted by PEX5 upon fasting, to maintain energy homeostasis.
Subject(s)
Caenorhabditis elegans Proteins/metabolism , Fasting/adverse effects , Lipid Droplets/metabolism , Lipolysis/physiology , Peroxisome-Targeting Signal 1 Receptor/metabolism , Peroxisomes/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Spatio-Temporal Analysis , 3T3-L1 Cells/metabolism , Adipocytes/metabolism , Animals , Caenorhabditis elegans , Cues , Cytoskeleton , Kinesins/metabolism , Lipid Metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Nutrients , Peroxisome-Targeting Signal 1 Receptor/genetics , Peroxisomes/genetics , Signal TransductionABSTRACT
tRNA-derived small RNAs (tsRNAs) have been implicated in many cellular processes, yet the detailed mechanisms are not well defined. We previously found that the 3' end of Leu-CAG tRNA-derived small RNA (LeuCAG3'tsRNA) regulates ribosome biogenesis in humans by maintaining ribosomal protein S28 (RPS28) levels. The tsRNA binds to coding (CDS) and non-coding 3' UTR sequence in the RPS28 mRNA, altering its secondary structure and enhancing its translation. Here we report that the functional 3' UTR target site is present in primates while the CDS target site is present in many vertebrates. We establish that this tsRNA also regulates mouse Rps28 translation by interacting with the CDS target site. We further establish that the change in mRNA translation occurred at a post-initiation step in both species. Overall, our results suggest that LeuCAG3'tsRNA might maintain ribosome biogenesis through a conserved gene regulatory mechanism in vertebrates.
Subject(s)
Leucine/genetics , Protein Biosynthesis , Protein Processing, Post-Translational , RNA, Messenger/genetics , RNA, Small Untranslated/genetics , RNA, Transfer/genetics , Ribosomal Proteins/metabolism , Animals , Humans , Leucine/metabolism , Mice , Phylogeny , RNA, Messenger/metabolism , RNA, Small Untranslated/metabolism , RNA, Transfer/metabolism , Ribosomal Proteins/geneticsABSTRACT
SREBP1c is a key transcription factor for de novo lipogenesis. Although SREBP1c is expressed in pancreatic islets, its physiological roles in pancreatic ß-cells are largely unknown. In this study, we demonstrate that SREBP1c regulates ß-cell compensation under metabolic stress. SREBP1c expression level was augmented in pancreatic islets from obese and diabetic animals. In pancreatic ß-cells, SREBP1c activation promoted the expression of cell cycle genes and stimulated ß-cell proliferation through its novel target gene, PAX4 Compared with SREBP1c+/+ mice, SREBP1c-/- mice showed glucose intolerance with low insulin levels. Moreover, ß-cells from SREBP1c-/- mice exhibited reduced capacity to proliferate and secrete insulin. Conversely, transplantation of SREBP1c-overexpressing islets restored insulin levels and relieved hyperglycemia in streptozotocin-induced diabetic animals. Collectively, these data suggest that pancreatic SREBP1c is a key player in mediating ß-cell compensatory responses in obesity.
Subject(s)
Homeodomain Proteins/metabolism , Insulin-Secreting Cells/metabolism , Paired Box Transcription Factors/metabolism , Sterol Regulatory Element Binding Protein 1/metabolism , Animals , Apoptosis/genetics , Apoptosis/physiology , Cell Cycle/genetics , Cell Cycle/physiology , Cell Line , Cell Proliferation/genetics , Cell Proliferation/physiology , Chromatin Immunoprecipitation , Homeodomain Proteins/genetics , Immunohistochemistry , Male , Mice , Paired Box Transcription Factors/genetics , Real-Time Polymerase Chain Reaction , Sterol Regulatory Element Binding Protein 1/geneticsABSTRACT
Elevated lipid metabolism promotes cancer cell proliferation. Clear cell renal cell carcinoma (ccRCC) is the most common subtype of kidney cancers, characterized by ectopic lipid accumulation. However, the relationship between aberrant lipid metabolism and tumorigenesis in ccRCC is not thoroughly understood. Here, we demonstrate that ring finger protein 20 (RNF20) acts as a tumor suppressor in ccRCC. RNF20 overexpression repressed lipogenesis and cell proliferation by inhibiting sterol regulatory element-binding protein 1c (SREBP1c), and SREBP1 suppression, either by knockdown or by the pharmacological inhibitor betulin, attenuated proliferation and cell cycle progression in ccRCC cells. Notably, SREBP1c regulates cell cycle progression by inducing the expression of pituitary tumor-transforming gene 1 (PTTG1), a novel target gene of SREBP1c. Furthermore, RNF20 overexpression reduced tumor growth and lipid storage in xenografts. In ccRCC patients, RNF20 downregulation and SREBP1 activation are markers of poor prognosis. Therefore, RNF20 suppresses tumorigenesis in ccRCC by inhibiting the SREBP1c-PTTG1 axis.
ABSTRACT
SREBP1c is a key lipogenic transcription factor activated by insulin in the postprandial state. Although SREBP1c appears to be involved in suppression of hepatic gluconeogenesis, the molecular mechanism is not thoroughly understood. Here we show that CRY1 is activated by insulin-induced SREBP1c and decreases hepatic gluconeogenesis through FOXO1 degradation, at least, at specific circadian time points. SREBP1c(-/-) and CRY1(-/-) mice show higher blood glucose than wild-type (WT) mice in pyruvate tolerance tests, accompanied with enhanced expression of PEPCK and G6Pase genes. CRY1 promotes degradation of nuclear FOXO1 by promoting its binding to the ubiquitin E3 ligase MDM2. Although SREBP1c fails to upregulate CRY1 expression in db/db mice, overexpression of CRY1 attenuates hyperglycaemia through reduction of hepatic FOXO1 protein and gluconeogenic gene expression. These data suggest that insulin-activated SREBP1c downregulates gluconeogenesis through CRY1-mediated FOXO1 degradation and that dysregulation of hepatic SREBP1c-CRY1 signalling may contribute to hyperglycaemia in diabetic animals.
Subject(s)
Cryptochromes/metabolism , Feeding Behavior , Forkhead Box Protein O1/metabolism , Glucose/biosynthesis , Liver/metabolism , Proteolysis , Signal Transduction , Sterol Regulatory Element Binding Protein 1/metabolism , Animals , Cryptochromes/genetics , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/pathology , Disease Models, Animal , Gene Expression Regulation/drug effects , Gluconeogenesis/drug effects , Glucose/metabolism , HEK293 Cells , Humans , Hyperglycemia/complications , Hyperglycemia/pathology , Insulin/pharmacology , Male , Mice, Inbred C57BL , Models, Biological , Proteasome Endopeptidase Complex/metabolism , Proto-Oncogene Proteins c-mdm2/metabolism , Ubiquitin/metabolism , Ubiquitination , Up-RegulationABSTRACT
SREBP1c is a key transcription factor that regulates de novo lipogenesis during anabolic periods. However, the molecular mechanisms involved in the suppression of SREBP1c under nutritional deprivation are largely unknown. In this study, we demonstrate that the small ubiquitin-related modifier (SUMO) E3 ligase, a protein inhibitor of activated STAT Y (PIASy), sumoylates SREBP1c at Lys98, leading to suppression of the hepatic lipogenic program upon fasting-induced signals. In primary hepatocytes, ablation of PIASy stimulated intracellular lipid accumulation through the induction of SREBP1c and its target genes. Given that protein kinase A (PKA) plays important roles in catabolic responses, activated PKA enhances the sumoylation of SREBP1c and potentiates the interaction between SREBP1c and PIASy. Notably, overexpression of PIASy in obese db/db mice ameliorated hepatic steatosis, while suppression of PIASy in lean (wild-type) mice stimulated hepatic lipogenesis with increased expression of SREBP1c target genes. Furthermore, PKA-mediated SREBP1c phosphorylation augmented SREBP1c sumoylation, subsequently leading to degradation of SREBP1c via ubiquitination. Together, these data suggest that PKA-induced SREBP1c sumoylation by PIASy is a key regulatory mechanism to turn off hepatic lipogenesis during nutritional deprivation.
Subject(s)
Fasting/metabolism , Lipid Metabolism/physiology , Protein Inhibitors of Activated STAT/metabolism , Signal Transduction/physiology , Sterol Regulatory Element Binding Protein 1/metabolism , Sumoylation/physiology , Animals , COS Cells , Cells, Cultured , Chlorocebus aethiops , Cyclic AMP-Dependent Protein Kinases/genetics , Cyclic AMP-Dependent Protein Kinases/metabolism , Fasting/physiology , Hepatocytes/metabolism , Hepatocytes/physiology , Lipid Metabolism/genetics , Lipogenesis/genetics , Lipogenesis/physiology , Liver/metabolism , Liver/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Phosphorylation/genetics , Phosphorylation/physiology , Protein Inhibitors of Activated STAT/genetics , SUMO-1 Protein/genetics , SUMO-1 Protein/metabolism , Signal Transduction/genetics , Sterol Regulatory Element Binding Protein 1/genetics , Sumoylation/genetics , Transcription, Genetic/genetics , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination/genetics , Ubiquitination/physiologyABSTRACT
Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme that regulates cellular redox potential. In this study, we demonstrate that macrophage G6PD plays an important role in the modulation of proinflammatory responses and oxidative stress. The G6PD levels in macrophages in the adipose tissue of obese animals were elevated, and G6PD mRNA levels positively correlated with those of proinflammatory genes. Lipopolysaccharide (LPS) and free fatty acids, which initiate proinflammatory signals, stimulated macrophage G6PD. Overexpression of macrophage G6PD potentiated the expression of proinflammatory and pro-oxidative genes responsible for the aggravation of insulin sensitivity in adipocytes. In contrast, when macrophage G6PD was inhibited or suppressed via chemical inhibitors or small interfering RNA (siRNA), respectively, basal and LPS-induced proinflammatory gene expression was attenuated. Furthermore, macrophage G6PD increased activation of the p38 mitogen-activated protein kinase (MAPK) and NF-κB pathways, which may lead to a vicious cycle of oxidative stress and proinflammatory cascade. Together, these data suggest that an abnormal increase of G6PD in macrophages promotes oxidative stress and inflammatory responses in the adipose tissue of obese animals.
Subject(s)
Glucosephosphate Dehydrogenase/metabolism , Macrophages/metabolism , Oxidative Stress , Adipocytes/metabolism , Adipose Tissue/enzymology , Adipose Tissue/metabolism , Animals , Cell Line , Chemokine CCL2/biosynthesis , Fatty Acids, Nonesterified/metabolism , Female , Glucosephosphate Dehydrogenase/antagonists & inhibitors , Glucosephosphate Dehydrogenase/genetics , Green Fluorescent Proteins/genetics , Humans , Inflammation/immunology , Interleukin-1beta/biosynthesis , Interleukin-6/biosynthesis , Lipopolysaccharides/pharmacology , Macrophages/enzymology , Male , Mice , Mice, Inbred C57BL , NADP/pharmacology , NF-kappa B/metabolism , Obesity , Oxidation-Reduction , RNA Interference , RNA, Messenger/analysis , RNA, Small Interfering , Reactive Nitrogen Species/metabolism , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha/biosynthesis , p38 Mitogen-Activated Protein Kinases/metabolismABSTRACT
Accumulating evidence suggests that the circadian clock is closely associated with metabolic regulation. However, whether an impaired circadian clock is a direct cause of metabolic dysregulation such as body weight gain is not clearly understood. In this study, we demonstrate that body weight gain in mice is not significantly changed by restricting feeding period to daytime or nighttime. The expression of peripheral circadian clock genes was altered by feeding period restriction, while the expression of light-regulated hypothalamic circadian clock genes was unaffected by either a normal chow diet (NCD) or a high-fat diet (HFD). In the liver, the expression pattern of circadian clock genes, including Bmal1, Clock, and Per2, was changed by different feeding period restrictions. Moreover, the expression of lipogenic genes, gluconeogenic genes, and fatty acid oxidation-related genes in the liver was also altered by feeding period restriction. Given that feeding period restriction does not affect body weight gain with a NCD or HFD, it is likely that the amount of food consumed might be a crucial factor in determining body weight. Collectively, these data suggest that feeding period restriction modulates the expression of peripheral circadian clock genes, which is uncoupled from light-sensitive hypothalamic circadian clock genes.