Biology subjects

Tardiff, D. F.

Publications and source records attributed to Tardiff, D. F..

2 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↗