Open AccessEssential basal cytonemes take up Hedgehog in the Drosophila wing imaginal disc
Author(s) -
Weitao Chen,
Hai Huang,
Ryo Hatori,
Thomas B. Kornberg
Publication year - 2017
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.754
H-Index - 325
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.149856
Subject(s) - biology , imaginal disc , colocalization , patched , hedgehog , smoothened , microbiology and biotechnology , compartment (ship) , morphogen , anatomy , basal (medicine) , drosophila melanogaster , genetics , signal transduction , endocrinology , oceanography , geology , insulin , gene
Morphogen concentration gradients that extend across developmental fields form by dispersion from source cells. In the Drosophila wing disc, Hedgehog (Hh) produced by posterior compartment cells distributes in a concentration gradient to adjacent cells of the anterior compartment. We monitored Hh:GFP after pulsed expression and analyzed movements and co-localization of Hh, Patched (Ptc) and Smoothened (Smo) proteins tagged with GFP or mCherry and expressed at physiological levels from bacterial artificial chromosome transgenes. Hh:GFP moved to basal sub-cellular locations prior to release from posterior compartment cells that express it, and was taken up by basal cytonemes that extend to the source cells. Hh and Ptc were present in puncta that moved along the basal cytonemes and formed characteristic apical-basal distributions in the anterior compartment cells. The basal cytonemes required diaphanous, Scar, neuroglian, and synaptobrevin, and both the Hh gradient and Hh signaling declined under conditions in which the cytonemes were compromised. These findings show that in the wing disc, Hh distributions and signaling are dependent upon basal release and uptake, and on cytoneme-mediated movement. No evidence for apical dispersion was obtained.