A high-density CRISPR activation platform for mapping cancer dependencies and resistance pathways ex vivo and in vivo
TL;DR
Partita, a next-generation mouse whole-genome CRISPRa sgRNA platform, designed for unparalleled efficiency in gene activation studies, is introduced, unlocking new avenues for functional genomics and expanding the toolkit for discovering key drivers of biological processes across diverse research fields.
Abstract
CRISPR activation (CRISPRa) enables precise up-regulation of gene expression for ex vivo and in vivo applications. However, a lack of scalable, high-coverage tools has limited comprehensive genetic screening in murine models. Here, we introduce Partita, a next-generation mouse whole-genome CRISPRa sgRNA platform, designed for unparalleled efficiency in gene activation studies. Partita uses a high-density targeting strategy, deploying 10 sgRNAs per transcriptional start site, structured into five gene class-specific sublibraries to maximize transcriptional induction. To demonstrate the capabilities of Partita, we performed a series of large-scale screens: an in vitro enrichment/depletion screen, whole-genome CRISPRa screens in a double-hit lymphoma model to uncover resistance factors to proapoptotic drugs (venetoclax, nutlin-3a, and etoposide) and an in vivo screen to identify accelerators of MYC-driven lymphomagenesis. Each experiment revealed both expected and unexpected regulators, with high validation rates. By enabling robust gain-of-function screening, Partita unlocks new avenues for functional genomics and expands the toolkit for discovering key drivers of biological processes across diverse research fields.