Testing of Cis-Regulatory Elements by Targeted Transgene Integration in Zebrafish Using PhiC31 Integrase.

Herein we present several strategies for testing the function of cis-regulatory elements using the PhiC31 integrase system. Firstly, we present two different strategies to analyze the activity of candidate enhancer elements. Targeted integration of candidate enhancers into the same genomic location circumvents the variability-associated random integration and position effects. This method is suitable for testing of candidate enhancers identified through computational or other analyses a priori. Secondly, we present methodology for targeted integration of BACs into the same genomic location(s). By using additional reporters integrated into a BAC, this enables experimental testing whether cis-regulatory elements are functional in the sequence inserted in the BAC.