title: Four-jointed interacts with dachs, abelson and enabled and feeds back onto the Notch pathway to affect growth and segmentation in the Drosophila leg.
abstract: The molecular basis of segmentation and regional growth during morphogenesis of Drosophila legs is poorly understood. We show that four-jointed is not only required for these processes, but also can direct ectopic growth and joint initiation when its normal pattern of expression is disturbed. These effects are non-autonomous, consistent with our demonstration of both transmembrane and secreted forms of the protein in vivo. The similarities between four-jointed and Notch phenotypes led us to further investigate the relationships between these pathways. Surprisingly, we find that although four-jointed expression is regulated downstream of Notch activation, four-jointed can induce expression of the Notch ligands, Serrate and Delta, and may thereby participate in a feedback loop with the Notch signaling pathway. We also show that four-jointed interacts with abelson, enabled and dachs, which leads us to suggest that one target of four-jointed signaling is the actin cytoskeleton. Thus, four-jointed may bridge the gap between the signals that direct morphogenesis and those that carry it out.
authors.affiliation: Department of Biology, Texas A&M University, College Station, TX 77843-3258, USA.
authors.forename: G R
authors.initials: GR
authors.lastname: Buckles
authors.forename: C
authors.initials: C
authors.lastname: Rauskolb
authors.forename: J L
authors.initials: JL
authors.lastname: Villano
authors.forename: F N
authors.initials: FN
authors.lastname: Katz
mesh_terms: D000818:Animals; D019521:Body Patterning; D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins / Q000378:metabolism; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development*; D005121:Extremities / Q000254:growth & development*; D005246:Feedback; D019476:Insect Proteins / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D000072100:Jagged-1 Protein; D007596:Joints / Q000254:growth & development*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D051880:Receptors, Notch; D000072099:Serrate-Jagged Proteins; D015398:Signal Transduction
chemical_list: D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C092744:ENA-VASP proteins; D019476:Insect Proteins; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D000072100:Jagged-1 Protein; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; C497759:N protein, Drosophila; D009687:Nuclear Proteins; D051880:Receptors, Notch; C000606278:Ser protein, Drosophila; D000072099:Serrate-Jagged Proteins; C103968:dac protein, Drosophila; C064045:delta protein; C095900:fj protein, Drosophila