Project description:Our spatiotemporal data confirmed activation of Tbl1xr1 in hepatocytes after 2/3 hepatectomy. TBL1XR1 is a transcriptional cofactor inducing ubiquitination and degradation of NCoR/SMRT co-repressors and NCoR is a negative regulator of hepatocyte proliferation acting through histone deacetylases (HDACs). We have examined the role of TBL1XR1 in liver regeneration through in vivo shRNA knockdown using adeno-associated viruses (shNC and shTbl1xr1) specifically targeting hepatocytes. The knockdown of Tbl1xr1 results in impair hepatocyte proliferation.To investigate the downstream targets of TBL1XR1 during liver regenration, we here perform the bulk RNA-seq for shNC and shTbl1xr1 at D2 after hepatectomy. Our data show demonstrated that Tbl1xr1 knockdown not only led to reduced cell cycle genes but also to impaired fatty acid β-oxidation as the most obviously affected liver function.
Project description:TBL1XR1 gene is associated with multiple developmental disorders presenting several neurological aspects. The relative protein is involved in regulation of important cellular pathways and master regulators of transcriptional output including nuclear receptor repressors, Wnt signaling, and MECP2 protein. However, TBL1XR1 mutations (including complete loss of its functions) have not been experimentally studied in neurological context, leaving a lack of knowledge in the mechanisms at the basis of the diseases. We show that Tbl1xr1 knock-out mice exhibit behavioral and neuronal abnormalities. Either the absence of TBL1XR1, or point mutations interfering with stability/regulation of NCOR complex induced decreased proliferation and increased differentiation in neural progenitors. We suggest that this developmental unbalance is due to the failure in the regulation of MAPK cascade. Together, our results broaden the molecular and functional aftermath of TBL1XR1 deficiency associated with human disorders.
Project description:Diffuse large B-cell lymphomas (DLBCL) encompass a heterogeneous group of diseases derived from different stages of B-cell differentiation. The most clinically aggressive forms of DLBCL, C5/MCD, carry activating mutations in canonical B-cell signaling pathways, as well as early-occurring hits in the poorly-characterized gene TBL1XR1. Here, we investigated the role of TBL1XR1 mutations in the early steps of malignant transformation. We found that TBL1XR1 mutations disrupt germinal center development, and introduce a cell fate bias towards memory B (MB) cells. At the molecular level, TBL1XR1 mutations trigger a switch, by which the SMRT/HDAC3 co-repressor complex shuttles between the lineage-defining transcription factors BCL6 and BACH2. We further demonstrate that terminal differentiation of TBL1XR1 mutant MB is limited upon recall, and that these MB re-enter the germinal center reaction instead, suggesting a role for these cells as the cell-of-origin of C5/MCD DLBCL.
Project description:Partial hepatectomy, resection of a portion of liver mass, indues significant liver regenerative responses that consist of numerous genetic changes. To identify specific genetic changes, we compare the liver of mice underwent either hepatectomy or sham operation.
Project description:Deletion of the RPS6 gene in mouse liver results in the inhibition of 40S ribosome biogenesis and the failure of hepatocytes to enter S-phase following partial hepatectomy. This microarray experiment was designed to assess the effects of RPS6 deletion on the expression of genes involved in liver regeneration following partial hepatectomy. Keywords: time course, liver