bioRxiv Science⌕ Search

Biology subjects

Edwards, J. J.

Publications and source records attributed to Edwards, J. J..

2 recordsLinked to original sources

Scalable in vivo cardiac functional genomics with compressed AAV-Perturb-seq reveals a common mitochondrial response to perturbation

Efficient identification of new targets to treat human disease requires a scalable way to link genotype to phenotype directly in the target organ. Pooled CRISPR screening with single-cell RNA sequencing as a readout (Perturb-seq) has emerged as a method for functional genomics but is typically applied in vitro and is limited in scale. Here, we combine in vivo Perturb-seq via adeno-associated virus (AAV)-mediated delivery with a statistical framework allowing for signal deconvolution after multiple random perturbations per cell (compressed Perturb-seq), to develop in vivo compressed AAV-Perturb-seq, a scalable way to perform high-throughput, cell-autonomous functional genomics in a desired target organ. We apply this approach to study the effect of 585 gene knockouts on the cardiomyocyte transcriptome. We identify that alterations in the mitochondrial transcriptome are a common response to genetic perturbation, a finding independently validated across species and perturbation modalities. We identify very few synergistic perturbations, despite observing frequent combinatorial effects. Broadly, our work establishes a platform to facilitate in vivo functional genomics in a target organ with direct applicability to identifying therapeutic targets for the treatment of human disease.

genomics↗

ROR2 drives right ventricular heart failure via disruption of proteostasis

BackgroundNo therapies exist to reverse right ventricular failure (RVF), and the molecular mechanisms that drive RVF remain under studied. We recently reported that the developmentally restricted noncanonical WNT receptor ROR2 is upregulated in human RVF in proportion to severity of disease. Here we test the mechanistic role of ROR2 in RVF pathogenesis. MethodsROR2 was overexpressed or knocked down in neonatal rat ventricular myocytes (NRVMs) and then characterized using confocal microscopy, RNAseq, proteomics, proteostatic functional assays, and pacing to assess contractile properties. The impact of cardiac ROR2 expression was evaluated in mice by AAV9-mediated overexpression and by AAV9-mediated delivery of shRNA to knockdown ROR2 in a pulmonary artery banded pressure overload model of RVF. ROR2-modified mice were evaluated by echocardiography, histology, and RV protein synthesis and proteasome capacity. ResultsIn NRVMs, we find that ROR2 profoundly dysregulates the coordination between protein translation and folding. This imbalance leads to excess protein clearance by the ubiquitin proteasome system (UPS) with dramatic impacts on sarcomere and cytoskeletal structure and function. Inhibiting the UPS or restoring chaperone expression is sufficient to partially rescue ROR2-induced structural and contractile deficits in cardiomyocytes. In mice, forced cardiac ROR2 expression is sufficient to disrupt proteostasis and drive RVF, while conversely ROR2 knockdown partially rescues proteostasis and RV structure and function in a pressure overload model of RVF. ConclusionsIn sum, ROR2 is a key driver of RVF pathogenesis through proteostatic disruption and, thus, provides a promising target to treat RVF.

molecular biology↗