Pooled CRISPR screens identifies key regulators of bovine stem cell expansion for cultured meat.

Cultured meat presents a sustainable alternative to traditional meat production but faces significant challenges in scalability and cost efficiency. A key limitation is the restricted proliferation capacity of bovine mesenchymal stem cells (bMSCs), a widely used cell source in the field. Using a pooled, lentiviral CRISPR knockout screen, we interrogated 3000 CRISPR guides targeting 600 genes involved in stem cell regulation or proliferation. Notably, knockouts of TP53 and PTEN significantly increased proliferation rates and delayed senescence. Validation with individual gene knockouts confirms these effects, showing enhanced growth but reduced differentiation potential. We also identified chondrogenic differentiation as a promising target whose repression may further promote MSC expansion. These findings demonstrate the utility of CRISPR screening for optimizing bovine stem cell traits and offer a path toward more scalable cultured meat production in the future.