Protein
1. The GFP exon is in an intron between two coding exons of a known or predicted gene product, in the applicable reading frame. Expression of a GFP-fusion protein is expected.
2. Also included in this category are lines with GFP upstream of coding sequence that we verified by RNA analysis were splicing to the ATG-containing exon. This results in an N-terminal fusion of GFP to the protein.
FlyTrap Project Information
Protein trapping screens
This database presents the current results of large scale protein trapping screens that provide both information on which cells express each tagged gene, and subcellular localization of GFP-tagged proteins. Expression is under the control of endogenous promoter and enhancer elements, allowing for visualization of normal expression patterns. Drosophila proteins tagged with Green Fluorescent Protein (GFP) were created by insertion into genes of an artificial exon encoding GFP flanked by splice acceptor (SA) and splice donor (SD) sequences so that expression of GFP relies on splicing into mature mRNAs and in-frame fusion. The original screen was developed in Bill Chia's lab and published in Morin et al.
Enhancer
The GFP exon is within 500bp upstream of a gene, but not within coding sequence. Expression of GFP is controlled by nearby enhancers, and results from introduction of start and stop codons by splicing to either transposon or genomic DNA.
Enhancer Opposite
The GFP exon is in a gene, but in the opposite orientation to the coding sequence the gene. Expression of GFP is controlled by enhancer elements.
No Gene/Novel
The GFP exon is inserted greater than 500 bp from any annotated gene. Expression may result from the presence of unannotated gene sequences, previously undocumented promoters and alternative translation starts, or undetected secondary GFP insertions.
Protein?
The GFP exon upstream of the coding sequence of a known or predicted gene product. Splicing to the ATG-containing exon likely results in an N-terminal fusion of GFP to the protein.
1
2
FlyTrap Website
This searchable and browsable database contains sequence coordinates of inserted transposons, information on the tagged genes, and images with expression patterns of GFP in Drosophila tissues. FlyTrap serves as the data repository for lines generated in the Chia, Cooley, and Spradling labs.
Various iterations of this web site were designed and modified by Reed Kelso (Kelso et al.), Remko DeKnikker, and Tony Melillo at Yale. Flytrap was implemented using the open source MySQL database system, V5. Our web server is running Red Hat Enterprise Linux Advance Server V4 with Apache web server V2. The front end was implemented using PHP (PHP: Hypertext Preprocessor) V5. The system also incorporates the open source GD (gif-draw) library V2 to generate the gene insertion diagrams. Routine updates to the MySQL database are made from a FileMaker Pro (V7) database shared through FileMaker Server 7 running on the Flytrap Macintosh server. Some functionality has been added by calling external Perl scripts.
A joint project, initiated by Mike Buszczak and involving the Cooley lab at Yale University (Quiñones-Coello et al.) and the Spradling lab at the Carnegie Institution of Washington (Buszczak et al.), has accelerated the screening process by employing automated embryo sorters to examine millions of Drosophila embryos. Individual GFP-positive embryos were collected and allowed to develop to adulthood. Stocks were established from individual adults and matings were done to remove the starting elements and transposase source. The insertion sites in the resulting lines were determined by sequencing DNA flanking the transposons. Many of the flanking sequences were determined by the Drosophila Gene Disruption Project under the direction of Roger Hoskins at the Lawrence Berkeley Laboratory.
Ovaries and other tissues were examined for cellular and subcellular patterns of GFP-fusion protein expression. The position of insertions relative to genes, and the expression patterns of GFP revealed that we recovered both the expected Protein Traps, and also Enhancer Traps.
