Figure 1

Design of artificial reproductive barriers. An artificial barrier combines dCas9 fused to an Activation Domain (AD) and an sgRNA targeting the promoter or enhancer region of a developmental gene within a protected genome. Protection is achieved by an INDEL mutation at the sgRNA binding site (red triangle) that prevents specific dCas9 binding but maintains target gene function. When a transgenic is crossed to wild-type flies the transgene cannot be inherited as synthetic lethality is triggered. Lethality is caused in hybrids when the native target gene is misexpressed ectopically by CRIPSR transactivation.