High impact information on cg

• Wg signal reception downregulates combgap expression and derepresses target gene transcription [1].
• Here we show that mutations in combgap (cg) result in deregulation of CI expression, which is now expressed at much lower levels and ubiquitously, i.e., also in the posterior [2].
• Transcriptional regulation of the Hedgehog effector CI by the zinc-finger gene combgap [2].
• The combgap locus encodes a zinc-finger protein that regulates cubitus interruptus during limb development in Drosophila melanogaster [3].
• We are able to rescue anterior compartment combgap phenotypes by expressing additional cubitus interruptus using the Gal4/UAS system [3].

Biological context of cg

• We show that Combgap, a zinc finger protein, represses Wg target gene expression in the visual cortex [1].
• Dominant alleles of cubitus interruptus, which result in posterior expression, phenocopy combgap posterior compartment phenotypes [3].
• Finally, we find that the combgap protein binds to polytene chromosomes at many sites including the cubitus interruptus locus, suggesting that it could be a direct regulator of cubitus interruptus transcription [3].

Anatomical context of cg

• Combgap is thus a tissue-specific relay between Wingless and its target genes for the determination of cell fate in the visual cortex [1].

Other interactions of cg

• Combgap relays wingless signal reception to the determination of cortical cell fate in the Drosophila visual system [1].
• The comb gap (cg) mutation, which also interacts with ds, greatly enhances the tendency of imaginal discs from l(2)gd larvae to duplicate as they overgrow [4].

References