Project description:Understanding the liver stem cells (LSCs) holds great promise for new insights into liver diseases and liver regeneration. By employing single-cell RNA-seq technology with weighted gene co-expression network analyses (WGCNA), we examined transcriptome features of distinct Krt19 lineage-tracing cell types isolated from Krt19CreERT; Rosa26R-GFP reporter mice, and identified gene expression signatures of quiescent and active adult LSCs, as well as their downstream lineage-restricted progenitors and terminally differentiation hepatocytes and cholangiocytes. Importantly, we discovered a novel cell surface LSC marker, CD63, as well as CD56, which distinguished active and quiescent LSCs. Furthermore, we confirmed that CD63+CD56- quiescent LSCs resided in Canals of Hering and peribiliary glands and that these cells could be activated by a combined action of VEGF and bFGF, and subsequently underwent terminal differentiation. These findings define an authentic adult liver stem cells compartment and highlight its contribution to liver homeostasis during pathophysiologic processes.
Project description:Understanding the liver stem cells (LSCs) holds great promise for new insights into liver diseases and liver regeneration. By employing single-cell RNA-seq technology with weighted gene co-expression network analyses (WGCNA), we examined transcriptome features of distinct Krt19 lineage-tracing cell types isolated from Krt19CreERT; Rosa26R-GFP reporter mice, and identified gene expression signatures of quiescent and active adult LSCs, as well as their downstream lineage-restricted progenitors and terminally differentiation hepatocytes and cholangiocytes. Importantly, we discovered a novel cell surface LSC marker, CD63, as well as CD56, which distinguished active and quiescent LSCs. Furthermore, we confirmed that CD63+CD56- quiescent LSCs resided in Canals of Hering and peribiliary glands and that these cells could be activated by a combined action of VEGF and bFGF, and subsequently underwent terminal differentiation. These findings define an authentic adult liver stem cells compartment and highlight its contribution to liver homeostasis during pathophysiologic processes.
Project description:A series of dual-channel gene expression profiles obtained using Rosetta/Agilent Whole Mouse Genome oligonucleotide microarrays, 4 x 44K format, was used to identify sex-dependent and HNF4alpha-dependent differences in gene expression in adult mouse liver. This series is comprised of four sex-genotype combinations: adult male wild-type liver (M-WT), adult female wild-type liver (F-WT), adult male liver-specific HNF4alpha knockout liver (M-KO) and adult female liver-specific HNF4alpha knockout liver (F-KO). Four pools, each comprised of 4 randomly selected individual liver RNAs, were prepared for each sex-genotype combination. The pools were paired randomly to generate 4 separate experimental comparisons: M-WT:F-WT (first array comparison), M-WT:M-KO (second array comparison), F-WT:F-KO (third array comparison), and M-KO:F-KO (fourth array comparison). A total of 4994 HNF4alpha-dependent genes were identified, of which ~1000 fewer genes responded to the loss of HNF4alpha in female liver as compared to male liver. Moreover, 90% of the genes showing sex-specific expression in the liver were shown to lose sex specificity in HNF4alpha-deficient liver. Keywords: genetic knockout and sex response
Project description:Lack of change in microRNA expression in adult mouse liver following treatment with benzo(a)pyrene (BaP), as detected using Agilent miRNA arrays. We have investigated the effect of exposure to 150 mg/kg benzo(a)pyrene (BaP) for 3 days on mRNA and miRNA expression levels in adult mouse liver. We used Agilent miRNA array platforms to assess effects of BaP exposure on miRNA expression levels. Our results indicate a distinct lack of effect of BaP of miRNA expression, despite widespread changes in mRNA levels. Keywords: Toxicology, miRNA