Control of a genetic regulatory network by a selector gene

The formation of many complex structures is controlled by a special class o f transcription factors encoded by selector genes. it is shown that SCALLOP ED, the DNA binding component of the selector protein complex for the Droso phila wing field, binds to and directly regulates the cis-regulatory elemen ts of many individual target genes within the genetic regulatory network co ntrolling wing development. Furthermore, combinations of binding sites for SCALLOPED and transcriptional effecters of signaling pathways are necessary and sufficient to specify wing-specific responses to different signaling p athways. The obligate integration of selector and signaling protein inputs on cis-regulatory DNA may be a general mechanism by which selector proteins control extensive genetic regulatory networks during development.