These stocks carry either a Kozak-GAL4 insertion or an intronic cassette containing a T2A (aka Trojan)-GAL4 exon. In general, both types are designed to knock-out the targeted fly gene and express GAL4 in the native gene pattern.

T2A-GAL4
T2A (aka Trojan)-GAL4 cassettes are composed of a splice acceptor, T2A peptide, GAL4 coding sequence and an Hsp70 transcription termination signal. The resulting gene trap is predicted to express GAL4 and a truncated gene product (often non-functional depending on the location of the gene trap) under endogenous gene control. These cassettes usually contain attP sites and are swappable.

We carry multiple types of T2A-GAL4 lines.
1. Mi{Trojan-GAL4} and Mi{DH} lines carry RMCE-mediated swap-ins of a T2A-GAL4 cassette into a Mi{MIC} insertion as described by Diao et al., 2015 and Li-Kroeger, 2018, respectively. See our Trojan donor and Double Header donor cassette pages for more details. The majority of these were generated by Hugo Bellen and the Gene Disruption Project. The 4th chromosome Mi{DH} lines were generated by Stuart Newfeld and the Fourth Chromosome Resource Project.

2. TI{CRIMIC.TG4} lines carry CRISPR-mediated insertions of a T2A-GAL4 cassette flanked by both attP and FRT sites as described in Lee et al., 2018. Lines are being generated by the Gene Disruption Project and the labs of Hugo Bellen and Norbert Perrimon.

Kozak-GAL4
For genes that lack suitable introns for the T2A-GAL4 approach, the Gene Disruption Project is replacing the coding sequence of the gene with a Kozak-GAL4 cassette as described in Kanca et al., 2022. The resulting gene trap removes most or all of the coding sequence and is predicted to express GAL4 under endogenous gene control. These cassettes do not contain attP sites and are not swappable.

Expression data for most lines can be found under the links in the "Expression Info" column. Many of the lines are targeted to genes that are orthologues of human disease genes. UAS constructs expressing many of the human genes can be found on the UAS-human gene page.