Role of dpp signalling in prepattern formation of the dorsocentral mechanosensory organ in Drosophila melanogaster.
A proneural cluster of dorsocentral bristles forms adjacent to the dorsal side of wg-expressing cells in the notum region of the wing imaginal disc. It has been shown that wg activity is required for these structures to form. However, the restriction of this proneural cluster to the dorsal posterior side of the wg expression domain in the anterior compartment of the wing imaginal disc has suggested that Wg signalling itself is insufficient to establish the dorsocentral proneural cluster. Some factor(s) from the posterior side must participate in this action in cooperation with Wg signalling. We have examined the role of Dpp signalling in dorsocentral bristle formation by either ectopically activating or conditionally reducing Dpp signalling. Ubiquitous activation of Dpp signalling in the notum region of the wing imaginal disc induced additional dorsocentral proneural cluster all along the dorsal side of the wg expression domain, and altered wg expression. Conditional loss-of-function of Dpp signalling during disc development resulted in the inhibition of dorsocentral proneural cluster formation and expansion of the wg expression domain. These results suggest that Dpp signalling has two indispensable roles in dorsocentral bristle formation: induction of the dorsocentral proneural cluster in cooperation with Wg signalling and restriction of the wg expression domain in the notum region of the wing imaginal disc.
Tomoyasu
Y
Y
Division of Morphogenesis, Department of Developmental Biology, National Institute for Basic Biology, and Department of Molecular Biomechanics, School of Life Science, The Graduate University for Advanced Studies, Japan. mack@nibb.ac.jp.
Nakamura
M
M
Ueno
N
N
D029404:Activin Receptors; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D019521:Body Patterning; D004268:DNA-Binding Proteins / Q000378:metabolism; D004330:Drosophila / Q000196:embryology*; D029721:Drosophila Proteins; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000378:metabolism / Q000502:physiology*; D008465:Mechanoreceptors / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism; D017978:Receptors, Growth Factor / Q000378:metabolism; D012097:Repressor Proteins; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000378:metabolism / Q000502:physiology; D051155:Wnt1 Protein
D029404:Activin Receptors; D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D011956:Receptors, Cell Surface; D017978:Receptors, Growth Factor; D012097:Repressor Proteins; D016212:Transforming Growth Factor beta; D051155:Wnt1 Protein; C064196:dpp protein, Drosophila; C063577:emc protein, Drosophila; C074622:wg protein, Drosophila; C090169:tkv protein, Drosophila