The hexapeptide and linker regions of the AbdA Hox protein regulate its activating and repressive functions.
The Hox family transcription factors control diversified morphogenesis during development and evolution. They function in concert with Pbc cofactor proteins. Pbc proteins bind the Hox hexapeptide (HX) motif and are thereby thought to confer DNA binding specificity. Here we report that mutation of the AbdA HX motif does not alter its binding site selection but does modify its transregulatory properties in a gene-specific manner in vivo. We also show that a short, evolutionarily conserved motif, PFER, in the homeodomain-HX linker region acts together with the HX to control an AbdA activation/repression switch. Our in vivo data thus reveal functions not previously anticipated from in vitro analyses for the hexapeptide motif in the regulation of Hox activity.
Laboratoire de Génétique et Physiologie du Développement, IBDM, CNRS, Université de la méditerranée, Parc Scientifique de Luminy, Case 907, 13288 Marseille Cedex 09, France.
Samir
S
Merabet
Zakaria
Z
Kambris
Maria
M
Capovilla
Hélène
H
Bérenger
Jacques
J
Pradel
Yacine
Y
Graba
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D017124:Conserved Sequence; D018983:DNA Footprinting; D029721:Drosophila Proteins / Q000737:chemistry* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000737:chemistry* / Q000378:metabolism*; D017403:In Situ Hybridization; D008648:Mesoderm / Q000378:metabolism; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000378:metabolism*; D009687:Nuclear Proteins; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000378:metabolism
D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; C083405:exd protein, Drosophila; C108704:hth protein, Drosophila; C066591:abd-A protein, Drosophila