The Drosophila split-GAL4 system, first described in Luan et al., 2006, allows for restricted expression of regulatory targets only in cells where the two components of the split-GAL4 activator are co-expressed. As shown below, the GAL4 DNA-binding domain fused to the Zip- protein-pairing domain can be expressed in one pattern, a transcriptional activation domain fused to the Zip+ protein-pairing domain can be expressed in another pattern and the UAS reporter construct will be expressed in the intersection of the two patterns. We now have thousands of stocks that carry either 1) a construct that expresses a DNA-binding domain protein derived from either GAL4 or lexA or 2) a construct that expresses a transcriptional activation domain derived from either GAL4, VP16 or p65.
Figure adapted from Dolan et al., 2017
Split-GAL4 driver expression patterns: The majority of our split-GAL4 lines were generated at either the Janelia Research Campus (donated by Gerry Rubin) or at the Institute of Molecular Pathology in Vienna (donated by Barry Dickson). Information on the expression profiles of these lines can be found on the GAL4 DBD and p65 AD pages.
Links to stocks carrying split-GAL4 hemidrivers
Stocks carrying split-GAL4 hemidrivers are divided into 5 categories based on how they were constructed, and links to these categories are provided below:
1) GAL4 DNA binding domain
2) p65 activation domain
3) GAL4 activation domain
4) lexA DNA binding domain
5) VP16 activation domain
6) Split-intein hemidrivers and combinations (Note, these are incompatible with the other stocks listed on this page)
Further restriction of split-GAL4-regulated expression patterns using Killer Zipper
Split GAL4 patterns can be further restricted by including a construct expressing a protein that competes with the activation domain for binding. See the Killer Zipper page for details.
Stocks carrying stable combinations of activation domain and DNA binding domain hemidrivers
For stocks expressing stable combinations of both activation and DNA-binding domains, see:
- Split GAL4 combination stocks
- Transcription-based calcium sensors