Pattern formation in the limbs of Drosophila: bric à brac is expressed in both a gradient and a wave-like pattern and is required for specification and proper segmentation of the tarsus.
We have identified the gene bric à brac and show that it is required for pattern formation along the proximal-distal axis of the leg and antenna of Drosophila. In bric à brac mutant legs, the bristle pattern of the three central tarsal segments is transformed towards the pattern of the most proximal tarsal segment. In addition, bric à brac mutant legs and antennae have segmentation defects. bric à brac encodes a nuclear protein that shares a highly conserved domain with two transcription factors from Drosophila. bric à brac function is dosage dependent and is required in a graded manner for the specification of tarsal segments. The graded requirement for bric à brac correlates with its graded expression pattern, suggesting that the concentration of BRIC A BRAC protein specifies segment identity in the tarsus.
Godt
D
D
Department of Biology, University of California at Los Angeles 90024.
Couderc
J L
JL
Cramton
S E
SE
Laski
F A
FA
D000818:Animals; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics; D005121:Extremities / Q000196:embryology*; D015870:Gene Expression / Q000502:physiology; D005801:Genes, Homeobox / Q000502:physiology*; D017403:In Situ Hybridization; D009024:Morphogenesis / Q000235:genetics; D009154:Mutation / Q000235:genetics; D010641:Phenotype