Project description:Using a mouse model with hepatocyte-specific deletion of transcription factor NF-κB RelA (p65), our group has previously revealed the important role of RelA in inducing the acute phase response, maintaining host defense, and preventing liver injury during sepsis. To goal of this study was determine the influence of RelA on hepatic gene changes that provide liver protection during infection. Mice were generated with functional deletion of NF-kappaB RelA (p56) in hepatocytes using a Cre-LoxP system. Mutant mice expressed Cre-recombinase under the transcriptional control of an albumin promotor and homozygous floxed RelA alleles. Wild type control mice lack the Cre-recombinase. Microarray analysis was performed on liver RNA collected from both genotypes of mice in the absence and presence of pneumococcal bacteremia.
Project description:Recent work using mouse models has revealed that mTORC2, which unlike mTORC1 is not acutely sensitive to rapamycin, plays a key role in the regulation of organismal physiology. The substrates and pathways regulated by mTORC2 are at present relatively unknown Using a mouse model with a targeted deletion of hepatic RICTOR, we investigated the loss of mTORC2 on the murine liver transcriptome Rictor floxed (RKO) and control mice (n=4 per group) were fasted overnight, refed for 3 hr, then sacrificed. Livers were removed, rinsed in PBS, and flash frozen in liquid nitrogen. RNA was extracted and hybridized to Affymetrix Genechip Mouse Gene 1.0 ST arrays
Project description:Recent work using mouse models has revealed that mTORC2, which unlike mTORC1 is not acutely sensitive to rapamycin, plays a key role in the regulation of organismal physiology. The substrates and pathways regulated by mTORC2 are at present relatively unknown Using a mouse model with a targeted deletion of hepatic RICTOR, we investigated the loss of mTORC2 on the murine liver transcriptome
Project description:We found that hepatic injury induced by PTEN loss establishes a selection pressure for tumorinitiating cells (TICs) to proliferate and form mixed lineage tumors. The Pten null mice demonstrate escalating levels of hepatic injury prior to proliferation of hepatic progenitors. Attenuation of hepatic injury by deleting Akt2 reduces progenitor cell proliferation and delays tumor development. Treatment of double mutant mice with 3,5-dietoxycarbonyl-1,4 dihydrocollidine (DDC) shows that the primary effect of AKT2 loss is attenuation of hepatic injury and not inhibition of progenitor cell proliferation in response to injury. Pten/Akt2 double mutant (PtenloxP/loxP; Akt2-/-; Alb-Cre+) (Dm) were generated by crossing the PtenloxP/loxP; Alb-Cre+ (Pm) with the Akt2-/- mice [19]. Control animals are PtenloxP/loxP; Albumin (Alb)-Cre-.
Project description:If the function of the nuclear receptor PPARa is well-known during a prolongated fasting, its hepatic biological function during feeding and refeeding conditions still needs to be investigated. Moreover, in vivo data collected so far on PPARa function during fasting were obtained using the total Ppara KO transgenic mouse model. To identify genes whose expression is under the strict dependence of hepatic PPARa activity, we generated a new mouse strain of PPARa-specific deletion in hepatocyte (albumin-Cre+/- Pparaflox/flox or LKO) and we compared them to total Ppara KO (KO), wild-type (WT) and liver WT (albumin-Cre-/- Pparaflox/flox or LWT) mice under three nutritional challenges. We used microarrays to detail the global programme of gene expression in liver of Ppara LKO, LWT, Ppara KO and WT male mice fed ad libitum, fasted for 24 hours and refed.
Project description:A common response to physiological duress is the hepatic acute phase response, a process during which the expression of many genes is altered in the liver. Amongst these transcripts are those encoding acute phase proteins, defined as circulating proteins with significantly changed concentrations during an acute phase response. The goal of this study was to determine the influence of STAT3 on hepatic gene changes including but not limited to acute phase proteins during bacterial pneumonia. Using the Cre-LoxP system, mice were generated with functional deletion of STAT3 in hepatocytes. In mutant mice, Cre-recombinase was expressed under transcriptional control of an albumin promoter in the presence of homozygous floxed alleles for STAT3. Wild-type control mice lacked the Cre-recombinase transgene. Microarray analysis was performed on liver RNA collected from both genotypes of mice in the absence and presence of pneumococcal pneumonia.
Project description:Notch intracellular domain (NICD) is the active form of the Notch receptor. In this mouse model, NICD is inserted in the Rosa26 locus downstream of a loxP-STOP-LoxP (lsl) sequence and therefore NICD expression is dependant on Cre recombinase expression. These mice are crossed with the AFP-Cre strain that expresses Cre in hepatoblasts due to its regulation by the AFP promoter and albumin enhancer. Mice from 6 to 12 months are sacrificed and liver RNA samples from control monotransgenic Rosa26-lsl-NICD and confirmed HCC lesions from bitransgenic AFP-Cre/Rosa26-lsl-NICD (AFP-NICD) are obtained. Exon expression profiling of these samples are submitted.
Project description:A common response to physiological duress is the hepatic acute phase response, a process during which the expression of many genes is altered in the liver. Amongst these transcripts are those encoding acute phase proteins, defined as circulating proteins with significantly changed concentrations during an acute phase response. The goal of this study was to determine the influence of NF-kappaB RelA (p65) on hepatic gene changes including but not limited to acute phase proteins during bacterial pneumonia. Using the Cre-LoxP system, mice were generated with functional deletion of NF-kappaB RelA (p65) in hepatocytes. In mutant mice, Cre-recombinase was expressed under transcriptional control of an albumin promoter in the presence of homozygous floxed alleles for RelA. Wild-type control mice lacked the Cre-recombinase transgene. Microarray analysis was performed on liver RNA collected from both genotypes of mice in the absence and presence of pneumococcal pneumonia.
Project description:Notch intracellular domain (NICD) is the active form of the Notch receptor. In this mouse model, NICD is inserted in the Rosa26 locus downstream of a loxP-STOP-LoxP (lsl) sequence and therefore NICD expression is dependant on Cre recombinase expression. These mice are crossed with the AFP-Cre strain that expresses Cre in hepatoblasts due to its regulation by the AFP promoter and albumin enhancer. Mice from 6 to 12 months are sacrificed and liver RNA samples from control monotransgenic Rosa26-lsl-NICD and confirmed HCC lesions from bitransgenic AFP-Cre/Rosa26-lsl-NICD (AFP-NICD) are obtained. Exon expression profiling of these samples are submitted. Four liver samples from monotransgenic mice (control) and five hepatocellular carcinoma samples from bitransgenic mice are analyzed using the Affymetrix GeneChip Mouse Gene 1.0 ST Array platform. Array data was preprocessed and analyzed using GenePattern software and R.