Analysis of a cis-regulatory element of the Drosophila Abdominal-B homeotic gene. H. Green , JA. Kennison. Laboratory of Molecular Genetics, NICHD/NIH, Bethesda, MD.

   Segment identities in Drosophila are specified by the homeotic genes of the Antennapedia and bithorax complexes (ANTC and BXC). In Drosophila, the Abdominal-B (Abd-B) gene of the BXC specifies the identities of several posterior abdominal segments. Expression of Abd-B in the fifth abdominal segment requires the iab5 cis-regulatory region.
   Our aim is to identify trans-acting factors that regulate Abd-B in the fifth abdominal segment using a genetic approach. The current study describes a new mutation that shows genetic interactions with iab5 and may encode a novel trans-acting factor involved in the regulation of Abd-B.
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