Biology subjects

Golczer, G.

Publications and source records attributed to Golczer, G..

3 recordsLinked to original sources

bioRxiv2026

Antisense Oligonucleotides Targeting an LDLR Regulatory RNA Increase LDLR Expression and Reduce LDL-cholesterol in Vivo

Regulatory RNAs (regRNAs) are non-coding RNAs expressed from promoters and enhancers that modulate gene transcription. Targeting regRNAs with antisense oligonucleotides (ASOs) can increase transcription and presents a potential therapeutic strategy to restore expression in haploinsufficient diseases. This approach requires high-quality regRNA maps, identification of ASOs targeting actionable sequences, and translation of efficacy to relevant animal models. Here, we describe this approach for human low-density lipoprotein receptor (LDLR). We characterized LDLR regRNAs in HepG2 cells and human liver using epigenomic mapping and regRNA Capture-seq, and designed ASOs targeting these regRNAs. Several ASOs increased LDLR expression in cells and a lead was evaluated for efficacy in a humanized liver mouse model. ASO administration increased human LDLR mRNA and protein, while lowering LDL-cholesterol in plasma. These data provide a framework for the discovery and translation of ASOs that increase gene expression as a potential therapeutic approach for the treatment of haploinsufficient diseases.

molecular biology↗

bioRxiv2026

Profiling and Targeting of Regulatory RNAs to Upregulate Gene Expression

Transcription of long noncoding RNAs (lncRNAs), including enhancer RNAs (eRNAs) and promoter-associated RNAs (paRNAs), collectively termed regulatory RNAs (regRNAs), is a hallmark of active gene expression, yet it remains unknown whether regRNAs can be targeted to selectively enhance transcription in cis. We developed regRNA Capture-seq, a high-throughput method to profile regRNAs, and applied it to primary human hepatocytes, annotating thousands of regRNAs at [~]2,000 enhancers and promoters. Using this approach, we interrogated a genetically validated enhancer of the ornithine transcarbamylase (OTC) gene, mutations of which cause OTC deficiency (OTCD), the most common urea cycle disorder. Antisense oligonucleotides (ASOs) targeting enhancer-derived regRNAs led to dose-dependent upregulation of OTC in hepatocytes. Mechanistically, ASOs altered regRNA structure, elevated regRNA levels, displaced transcriptional repressors, and increased H3K27 acetylation at the targeted enhancer. This work establishes a potential therapeutic strategy for addressing haploinsufficiency and highlights regRNAs as actionable targets for ASO-mediated upregulation of gene expression.

genomics↗

bioRxiv2023

Transcriptional characterization of iPSC-derived microglia as a model for therapeutic development in neurodegeneration

BackgroundMicroglia are the resident immune cells in the brain that play a key role in driving neuroinflammation, a hallmark of neurodegenerative disorders. Inducible microglia-like cells have been developed as an in vitro platform for molecular and therapeutic hypothesis generation and testing. However, there has been no systematic assessment of similarity of these cells to primary human microglia along with their responsiveness to external cues expected of primary cells in the brain. MethodsIn this study, we performed transcriptional characterization of commercially available human inducible pluripotent stem cell (iPSC)-derived microglia-like (iMGL) cells by bulk and single cell RNA sequencing to assess their similarity with primary human microglia. To evaluate their stimulation responsiveness, iMGL cells were treated with Liver X Receptor (LXR) pathway agonists and their transcriptional responses characterized by bulk and single cell RNA sequencing. ResultsBulk transcriptome analyses demonstrate that iMGL cells have a similar overall expression profile to freshly isolated human primary microglia and express many key microglial transcription factors and functional and disease-associated genes. Notably, at the single-cell level, iMGL cells exhibit distinct transcriptional subpopulations, representing both homeostatic and activated states present in normal and diseased primary microglia. Treatment of iMGL cells with LXR pathway agonists induces robust transcriptional changes in lipid metabolism and cell cycle at the bulk level. At the single cell level, we observe heterogeneity in responses between cell subpopulations in homeostatic and activated states and deconvolute bulk expression changes into their corresponding single cell states. ConclusionsIn summary, our results demonstrate that iMGL cells exhibit a complex transcriptional profile and responsiveness, reminiscent of in vivo microglia, and thus represent a promising model system for therapeutic development in neurodegeneration.

genomics↗