RNA-guided transcriptional regulation

A method of modulating expression of a viral gene in a cell in vitro comprising

• introducing into the cell a nucleic acid encoding a guide RNA fused to a target of an RNA-binding domain wherein the nucleic acid is operably linked to an expression control sequence, wherein the guide RNA is complementary to a viral target nucleic acid sequence comprising the viral gene,
• introducing into the cell a second nucleic acid encoding a transcriptional regulator protein or domain that modulates the target nucleic acid expression, and which is fused to an RNA-binding domain wherein the second nucleic acid is operably linked to an expression control sequence,
• introducing into the cell a third nucleic acid encoding a nuclease null Cas9 protein of a Type II CRISPR system, wherein the third nucleic acid is operably linked to an expression control sequence, wherein the nuclease null Cas9 protein interacts with the guide RNA which binds to the viral target nucleic acid sequence in a site specific manner,
• wherein the cell produces the guide RNA fused to the target of the RNA-binding domain, the Cas9 protein and the transcriptional regulator protein or domain fused to the RNA-binding domain,
• wherein the guide RNA and the Cas9 protein co-localize to the viral target nucleic acid sequence and wherein the transcriptional regulator protein or domain modulates expression of the viral gene.