Archaexpress: Regulated expression of specific mRNAs in the mouse induced by the expression of an archaeal endonuclease.

Abstract: We generated a new system for manipulating gene expression at the post-transcriptional level by expressing an archaeal endonuclease that excises small tRNA introns (Deidda et al.; Nature Biotech., 21:1499-1504, 2003). Archaea encode an RNA ligase that joins the resulting exonic fragments created by this action, and it turns out that mouse cells have an endogenous ligase with equivalent activity. The only requirement of the archaeal endonuclease is a bulge-helix-bulge recognition motif in its target RNAs, that is, a structure rather than a specific sequence; this allows great freedom in creating and presenting diverse targets in mRNA as well as structural RNA. We designed experiments to show the operation of this in vivo cis and trans splicing scheme in mouse cells and in mice. Induced trans-splicing results in the production of fusion-proteins. This emergent technology can be used to study protein networks.