Methods of Screening Using Barcoded Libraries

A method of screening comprising

• providing a combination of a plurality of proliferating cell types wherein each proliferating cell type has a unique associated barcode within its genome that is different from other proliferating cell types of the plurality and wherein each proliferating cell type includes a toxicity gene that when overexpressed causes toxicity to the proliferating cell type,
• introducing a perturbation to one or more of the plurality of proliferating cell types,
• inducing expression of one or more of the toxicity genes,
• determining the relative number of unique associated barcodes after a period of proliferation, and
• comparing the relative number of unique associated barcodes to a control relative number of unique associated barcodes to indicate the effect of the perturbation on the one or more of the plurality of proliferating cell types.

A method of screening comprising

• providing a yeast strain transformed with a plurality of vectors, with each vector in the plurality comprising a first nucleic acid sequence encoding a toxicity gene that when overexpressed causes toxicity to the yeast strain, a guide RNA having a spacer sequence complementary to a target nucleic acid sequence in the genome of the yeast strain, and a unique barcode associated with the toxicity gene and the guide RNA, and
• introducing an RNA guided DNA binding protein to the yeast strain,
• inducing expression of the first nucleic acid sequence of the plurality of vectors such that the toxicity gene is expressed and the guide RNA is produced within the yeast strain and colocalizes with the RNA guided DNA binding protein at the target nucleic acid sequence in the genome of the yeast strain and wherein the target nucleic acid is modulated,
• determining the relative number of unique barcodes associated with the toxicity gene and the guide RNA after a period of proliferation, and
• comparing the relative number of unique barcodes associated with the toxicity gene and the guide RNA to a control relative number of unique barcodes to indicate the effect of the modulation of the target nucleic acid on the yeast strain.