Tracheal progenitor outgrowth from the niche during Drosophila melanogaster metamorphosis
- Feng Chen.
- Aug. 2013.
- Physical description
- online resource (vi, 120 pages) : illustrations (some color)
- Chen, Feng.
- Fuller, Margaret T., 1951- thesis advisor.
- Kim, Stuart thesis advisor.
- Krasnow, Mark, 1956- thesis advisor (primary).
- Lipsick, Joseph Steven, 1955- thesis advisor.
- Stanford University. Department of Genetics.
- Stanford University. Committee on Graduate Studies. degree grantor.
- Includes bibliographical references (p. 119-120).
- While there has been great progress in identifying stem and progenitor cells and the signals that control their proliferation and differentiation, how stem/progenitor cells exit their niche and how they form new tissue is not well understood. Unlike in the embryo, tissue formation in an adult animal faces new challenges such as longer distances to migrate and a complex milieu of differentiated tissue to migrate around and/or coordinate with. To restore function to a tissue, stem/progenitor cells must also integrate into healthy tissue and coordinate growth with decaying tissue. In this thesis, I examine how tracheal progenitor cells exit their niche to form tracheal tissue during Drosophila melanogaster metamorphosis. Tracheal progenitors exit the niche in two waves. During the first wave, progenitors migrate onto the basal surface of larval tracheal branches destined for destruction, and track along the decaying branches. Progenitor outgrowth requires the embryonic tracheal branch inducer, Breathless FGFR, and surprisingly, the Branchless FGF ligand is expressed in larval branches along which progenitors crawl. In this way, outgrowth is coordinated with tissue decay. Progenitors that remain within the niche during the first wave exit later. However, instead of moving onto the basal surface of larval branches, progenitors exiting the niche during this second wave move along the apical surface, displacing larval cells, and repopulating the tracheal branch. This latter process does not resemble branching morphogenesis in the embryo and does not require Bnl/Btl FGF signaling, demonstrating that progenitor outgrowth does not always require embryonic guidance cues.
- Drosophila Proteins > physiology
- Drosophila melanogaster > embryology
- Fibroblast Growth Factors > physiology
- Metamorphosis, Biological
- Stem Cell Niche > physiology
- Trachea > embryology
- Cell Proliferation
- Receptors, Fibroblast Growth Factor > physiology
- Publication date
- Submitted to the Department of Genetics and the Committee on Graduate Studies of Stanford University.
- Thesis (Ph.D.)--Stanford University, 2013.