Chip-mediated partnerships of the homeodomain proteins Bar and Aristaless with the LIM-HOM proteins Apterous and Lim1 regulate distal leg development.
Proximodistal patterning in Drosophila requires division of the developing leg into increasingly smaller, discrete domains of gene function. The LIM-HOM transcription factors apterous (ap) and Lim1 (also known as dlim1), and the homeobox genes Bar and aristaless (al) are part of the gene battery required for the development of specific leg segments. Our genetic results show that there are posttranslational interactions between Ap, Bar and the LIM-domain binding protein Chip in tarsus four, and between Al, Lim1 and Chip in the pretarsus, and that these interactions depend on the presence of balanced amounts of such proteins. We also observe in vitro protein binding between Bar and Chip, Bar and Ap, Lim1 and Chip, and Al and Chip. Together with the previous evidence for interactions between Ap and Chip, these results suggest that these transcription factors form protein complexes during leg development. We propose that the different developmental outcomes of LIM-HOM function are due to the precise identity and dosage of the interacting partners present in a given cell.
Pueyo
Jose Ignacio
JI
School of Biological Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK.
Couso
Juan Pablo
JP
D000818:Animals; D019521:Body Patterning; D029721:Drosophila Proteins / Q000502:physiology*; D004331:Drosophila melanogaster; D005121:Extremities / Q000196:embryology*; D005136:Eye Proteins / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D005982:Glutathione Transferase / Q000378:metabolism; D018398:Homeodomain Proteins / Q000502:physiology*; D007150:Immunohistochemistry; D060850:LIM-Homeodomain Proteins; D008954:Models, Biological; D009154:Mutation; D009687:Nuclear Proteins / Q000502:physiology*; D010641:Phenotype; D011485:Protein Binding; D014176:Protein Biosynthesis; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014157:Transcription Factors / Q000502:physiology*; D014158:Transcription, Genetic; D060589:Zyxin
C072318:B-H1 protein, Drosophila; C108740:Chi protein, Drosophila; D029721:Drosophila Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D060850:LIM-Homeodomain Proteins; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; C499520:Zyx protein, Drosophila; D060589:Zyxin; C079410:al protein, Drosophila; C074459:ap protein, Drosophila; D005982:Glutathione Transferase