Developmental compartments in the larval trachea of Drosophila
Abstract
The Drosophila tracheal system is a branched tubular network that forms in the embryo by a post-mitotic program of morphogenesis. In third instar larvae (L3), cells constituting the second tracheal metamere (Tr2) reenter the cell cycle. Clonal analysis of L3 Tr2 revealed that dividing cells in the dorsal trunk, dorsal branch and transverse connective branches respect lineage restriction boundaries near branch junctions. These boundaries corresponded to domains of gene expression, for example where cells expressing Spalt, Delta and Serrate in the dorsal trunk meet vein-expressing cells in the dorsal branch or transverse connective. Notch signaling was activated to one side of these borders and was required for the identity, specializations and segregation of border cells. These findings suggest that Tr2 is comprised of developmental compartments and that developmental compartments are an organizational feature relevant to branched tubular networks.
Article and author information
Author details
Reviewing Editor
- Ginés Morata, Universidad Autónoma de Madrid, Spain
Version history
- Received: June 19, 2015
- Accepted: October 21, 2015
- Accepted Manuscript published: October 22, 2015 (version 1)
- Version of Record published: January 11, 2016 (version 2)
Copyright
© 2015, Rao et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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