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Buehler, D. P.

Publications and source records attributed to Buehler, D. P..

2 recordsLinked to original sources

The transcription factor ZNF469 regulates collagen production in liver fibrosis

Non-alcoholic fatty liver disease (NAFLD) - characterized by excess accumulation of fat in the liver - now affects one third of the worlds population. As NAFLD progresses, extracellular matrix components including collagen accumulate in the liver causing tissue fibrosis, a major determinant of disease severity and mortality. To identify transcriptional regulators of fibrosis, we computationally inferred the activity of transcription factors (TFs) relevant to fibrosis by profiling the matched transcriptomes and epigenomes of 108 human liver biopsies from a deeply-characterized cohort of patients spanning the full histopathologic spectrum of NAFLD. CRISPR-based genetic knockout of the top 100 TFs identified ZNF469 as a regulator of collagen expression in primary human hepatic stellate cells (HSCs). Gain- and loss-of-function studies established that ZNF469 regulates collagen genes and genes involved in matrix homeostasis through direct binding to gene bodies and regulatory elements. By integrating multiomic large-scale profiling of human biopsies with extensive experimental validation we demonstrate that ZNF469 is a transcriptional regulator of collagen in HSCs. Overall, these data nominate ZNF469 as a previously unrecognized determinant of NAFLD-associated liver fibrosis.

molecular biology↗

Combinatorial transcriptional profiling of mouse and human enteric neurons identifies shared and disparate subtypes in situ.

AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSBACKGROUND & AIMSC_ST_ABSThe enteric nervous system (ENS) coordinates essential intestinal functions through the concerted action of diverse enteric neurons (EN). However, integrated molecular knowledge of EN subtypes is lacking. To compare human and mouse ENs, we transcriptionally profiled healthy ENS from adult humans and mice. We aimed to identify transcripts marking discrete neuron subtypes and visualize conserved EN subtypes for humans and mice in multiple bowel regions. METHODSHuman myenteric ganglia and adjacent smooth muscle were isolated by laser-capture microdissection for RNA-Seq. Ganglia-specific transcriptional profiles were identified by computationally subtracting muscle gene signatures. Nuclei from mouse myenteric neurons were isolated and subjected to single-nucleus RNA-Seq (snRNA-Seq), totaling over four billion reads and 25,208 neurons. Neuronal subtypes were defined using mouse snRNA-Seq data. Comparative informatics between human and mouse datasets identified shared EN subtype markers, which were visualized in situ using hybridization chain reaction (HCR). RESULTSSeveral EN subtypes in the duodenum, ileum, and colon are conserved between humans and mice based on orthologous gene expression. However, some EN subtype-specific genes from mice are expressed in completely distinct morphologically defined subtypes in humans. In mice, we identified several neuronal subtypes that stably express gene modules across all intestinal segments, with graded, regional expression of one or more marker genes. CONCLUSIONSOur combined transcriptional profiling of human myenteric ganglia and mouse EN provides a rich foundation for developing novel intestinal therapeutics. There is congruency among some EN subtypes, but we note multiple species differences that should be carefully considered when relating findings from mouse ENS research to human GI studies. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=123 SRC="FIGDIR/small/187211v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@1b41277org.highwire.dtl.DTLVardef@12856feorg.highwire.dtl.DTLVardef@1674dadorg.highwire.dtl.DTLVardef@11ca1c8_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract C_FIG

neuroscience↗