Abstract
dc:description.abstractTHE ROLE OF PAX6 IN LENS PLACODE FORMATION by Jie Huang Washington University in St. Louis, 2010 Professor David Beeebe, Chairperson Although placodes are ubiquitous precursors of tissue invagination, the mechanism of placode formation and its importance for invagination are unclear. We tested the "restricted expansion hypothesis" of lens placode formation by conditionally deleting the transcription factor, Pax6, or the matrix component, Fn1. Deletion of Pax6 from the lens-forming ectoderm prevented placode formation without altering cell proliferation or volume. <italic>Pax6<super>CKO</super> </italic>ectoderm expanded, rather than being constrained to a constant area, as normally occurs during lens placode formation, and expressed lower levels of transcripts encoding several extracellular matrix components. Deletion of Fn1, which is required to organize the extracellular matrix, prevented lens placode formation. Consistent with the "restricted expansion hypothesis," <italic>Fn1<super>CKO </super> </italic> ectoderm expanded, rather than being constrained. Ectoderm cells of <italic>Fn1<super>CKO</super> </italic> embryos expressed markers of lens induction, reorganized their cytoskeleton as in wild type ectoderm, but did not invaginate. These results suggest that placode formation establishes the minimal mechanical requirements for tissue invagination.
Degree
thesis:*- Name thesis:degree_name
- Doctor of Philosophy (PhD)
- Level thesis:degree_level
- Dissertation
- Discipline thesis:degree_discipline
- Biology and Biomedical Sciences: Developmental, Regenerative and Stem Cell Biology
- Year dc:date.available
- 2010
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Huang, Jie
- Contributors dc:contributor
-
- David Beebe
Subjects
dc:subject × 9Rights
- Language dc:language
- English (en)
Identifiers
dc:identifier.*- OAI identifier oai:identifier
- oai:openscholarship.wustl.edu:etd-1159