Project description:We derived a model that allows for doxycycline-inducible deletion of Zfp423 in mature adipocytes of adult mice (Adiponectin-rtTA; TRE-CRE; Zfp423 loxP/loxP). In these animals deletion of Zfp423 results in a spontaneous conversion of white adipocytes into beige-like adipocytes at room temperature. The goal of this expression analysis was to 1) determine the gene programs dependent on adipocyte Zfp423 in inguinal WAT, and 2) determine the similarity between the converted beige-like cells to normal beige adipose tissue that accumulates upon cold exppsure.
Project description:We previously established the transcription factor Zfp423 is critical for maintaining white adipocyte identity through suppression of the thermogenic gene program. The loss of Zfp423 in mature adipocytes triggers the rapid conversion of energy-storing white adipocytes into thermogenic beige adipocytes in subcutaneous WAT. In contrast to subcutaneous WAT, visceral WAT is relatively resistant to browning. However, visceral adipocytes lacing Zfp423 are capable of inducing the thermogenic gene program upon β-3 adrenergic stimulus. Here, we generated mice lacking Zfp423 in visceral adipose by breeding transgenic mice expressing Cre recombinase under the control of the Wilms Tumor 1 locus (Wt1-Cre) to animals carrying the floxed Zfp423 alleles (Zfp423loxP/loxP) (“Vis-KO” mice). Inactivation of Zfp423 in visceral WAT gives rise to thermogenic adipocytes that share properties of subcutaneous beige adipocytes and classic brown adipocytes.
Project description:Energy-storing white adipocytes maintain their identity by suppressing the gene program defining energy-burning thermogenic brown/beige adipocytes. Here, we reveal that the protein-protein interaction between the transcriptional co-regulator ZFP423 and brown/beige cell determination factor, EBF2, is essential for restraining the thermogenic phenotype of white adipose tissue (WAT). Disruption of the ZFP423-EBF2 protein interaction through CRISPR-Cas9 gene editing triggers widespread “browning” of WAT in adult mice. Mechanistically, adipocyte Zfp423 deficiency induces an EBF2 NuRD-to-BAF co-regulator switch and a shift in PPARgamma occupancy to thermogenic genes. This shift in PPARgamma occupancy increases the anti-diabetic efficacy of the PPARgamma agonist rosiglitazone in obesity while diminishing the unwanted weight-gaining effect of the drug. These data indicate that ZFP423 controls EBF2 co-activator recruitment and PPARgamma occupancy to determine the thermogenic plasticity of adipocytes and raise the concept of targeting transcriptional brakes in adipocyte gene expression as a therapeutic strategy to induce thermogenic adipocyte biogenesis in obesity.
Project description:Energy-storing white adipocytes maintain their identity by suppressing the gene program defining energy-burning thermogenic brown/beige adipocytes. Here, we reveal that the protein-protein interaction between the transcriptional co-regulator ZFP423 and brown/beige cell determination factor, EBF2, is essential for restraining the thermogenic phenotype of white adipose tissue (WAT). Disruption of the ZFP423-EBF2 protein interaction through CRISPR-Cas9 gene editing triggers widespread “browning” of WAT in adult mice. Mechanistically, adipocyte Zfp423 deficiency induces an EBF2 NuRD-to-BAF co-regulator switch and a shift in PPARgamma occupancy to thermogenic genes. This shift in PPARgamma occupancy increases the anti-diabetic efficacy of the PPARgamma agonist rosiglitazone in obesity while diminishing the unwanted weight-gaining effect of the drug. These data indicate that ZFP423 controls EBF2 co-activator recruitment and PPARgamma occupancy to determine the thermogenic plasticity of adipocytes and raise the concept of targeting transcriptional brakes in adipocyte gene expression as a therapeutic strategy to induce thermogenic adipocyte biogenesis in obesity.
Project description:Two types of UCP1 positive cells-brown and beige adipocytes exist in mammals. Beige adipocytes are very plastic, and can be dynamically regulated by environment.Beige adipocytes formed postnatally in subcutaneous inguinal white adipose tissue (iWAT) lost thermogenic gene expression and multilocular morphology at adult stage, but cold could restore their “beigeing” characteristics, a phenomenon termed as beige adipocyte renaissance. Our results showed that beige cell maintenance and renaissance in adult mice were regulated by cAMP and HDAC4 signaling in white adipocytes non-cell autonomously. Genetic modulations of various components of this cAMP-HDAC4 cascade (e.g. LKB1) led to persistent browning and reduced adiposity independent of thermogenesis. To further study the mechanisms of beige adipocytes maintenance, we performed RNA-seq with samples from inguinal white adipose tissues of WT, AdipoqCre LKB1 F/F, and AdipoqCre LKB1 F/F; HDAC4 F/F mice.Our studies will move the beige adipocyte field forward and attract clinical applications to target beige adipocyte renaissance.
Project description:Committed preadipocyte fibroblasts were genetically labelled in transgenic mice by expressing GFP under the control of the locus for Zfp423, a gene controlling preadipocyte determination. These mice are herein referred to as Zfp423-GFP mice. The overall goal was to identify genes differentially expressed between adipogenic GFP+ firboblasts and non-adipogenic GFP- fibroblasts from either inguinal or epididymal fat stromal vascular cultures obtained from Zfp423-GFP mice. Adipose stromal vascular cultures were obtained from inguinal or epididymal fat of 6-8 week-old male Zfp423-GFP mice. GFP+ and GFP- fibroblasts were sorted from fat stromal vascular cultures and then returned to culture. Subconfluent cultures of GFP+ and GFP- cells were compared in triplicate for Affymetrix analysis.
Project description:In order to select mRNA transcripts strongly enriched in murine white adipocytes versus brown adipocytes or stromal-vascular fraction, gene expression data of the adipocyte and stromal-vascular fractions of the interscapular brown, inguinal subcutaneous as well as visceral epididymal adipose tissue depots of young adult male C57BL/6 mice housed at constant 23°C ambient temperature were obtained.
Project description:In order to select mRNA transcripts strongly enriched in murine white adipocytes versus brown adipocytes or stromal-vascular fraction, gene expression data of the adipocyte and stromal-vascular fractions of the interscapular brown, inguinal subcutaneous as well as visceral epididymal adipose tissue depots of young adult male C57BL/6 mice housed at constant 23°C ambient temperature were obtained. 18 samples: 3 different adipose tissues separated into stromal-vascular fraction and adipocytes, analyzed in biological triplicates.
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:Purpose: To generate gene expression profiles of inguinal white, epididymal white and interscapular brown adipocytes Methods: Translating ribosomal affinity purification (TRAP) using an adipocyte-specific cre in adult wildtype mice followed by RNA-Seq Results: Using an optimized data analysis workflow, we mapped about 30 million sequence reads per sample to the mouse genome (build mm9) using Tophat and assembled reads into transcripts using Cufflinks.