Biology subjects

Ardy, R. C.

Publications and source records attributed to Ardy, R. C..

2 recordsLinked to original sources

bioRxiv2026

Scaling perturbations: beyond genome-scale CRISPR screens

CRISPR screens have become essential tools for systematically probing gene function from basic biology to drug discovery, yet important frontiers remain beyond genome scale. Probing regulatory elements, interpreting genetic variants, and mapping genetic interactions all challenge the sensitivity and scalability of existing approaches. Here we introduce two synergistic technologies to address these limitations. PORTAL (Perturbation Output via Reporter Transcriptional Activity in Lineages) shifts pooled genetics toward quantitative RNA phenotypes, encoding perturbation effects in expressed transcripts to enable single-molecule measurements with lineage or single-cell resolution. CAP cloning (Covalently closed Assembly Products) bypasses bacterial transformation to enable construction of ultrahigh-complexity lentiviral libraries. Combining these advances, we construct a genetic interaction map spanning 665,856 pairwise perturbations across 46 million clonal lineages--the largest exhaustive map in human cells and the first at this scale using a non-fitness phenotype. More broadly, this work charts a path toward comprehensive genetic interaction mapping in human cells.

systems biology↗

bioRxiv2024

Comprehensive transcription factor perturbations recapitulate fibroblast transcriptional states

Cell atlas projects have nominated recurrent transcriptional states as drivers of biological processes and disease, but their origins, regulation, and properties remain unclear. To enable complementary functional studies, we developed a scalable approach for recapitulating cell states in vitro using CRISPR activation (CRISPRa) Perturb-seq. Aided by a novel multiplexing method, we activated 1,836 transcription factors in two cell types. Measuring 21,958 perturbations showed that CRISPRa activated targets within physiological ranges, that epigenetic features predicted activatable genes, and that the protospacer seed region drove an off-target effect. Perturbations recapitulated in vivo fibroblast states, including universal and inflammatory states, and identified KLF4 and KLF5 as key regulators of the universal state. Inducing the universal state suppressed disease-associated states, highlighting its therapeutic potential. Our findings cement CRISPRa as a tool for perturbing differentiated cells and indicate that in vivo states can be elicited via perturbation, enabling studies of clinically relevant states ex vivo.

systems biology↗