PUBLICATION
Genetic analysis of somitogenesis in the zebrafish, Danio rerio
- Authors
- Dill, K.K.
- ID
- ZDB-PUB-090529-38
- Date
- 2005
- Source
- Ph.D. Thesis : 128p (Thesis)
- Registered Authors
- Dill, Kariena
- Keywords
- Biological sciences, Somitogenesis, Segmentation clock, Presomitic mesoderm, tortugab644, deltaC
- MeSH Terms
- none
- PubMed
- none
Citation
Dill, K.K. (2005) Genetic analysis of somitogenesis in the zebrafish, Danio rerio. Ph.D. Thesis. :128p.
Abstract
Current models suggest that the oscillating expression of Notch pathway genes in the presomitic mesoderm (PSM) is a key factor in the regulation of somite formation. I used a genetic approach to study the regulation of oscillating gene expression during zebrafish segmentation. I performed a phenotypic analysis of tortugab644, an ENU-induced mutation that disrupts the PSM expression of Notch pathway genes. In tortuga (tor) mutants, Notch pathway gene expression persists in regions of the PSM where expression is normally off in wild type embryos. Expression of hairy/Enhancer of split-related 1 ( her1) is affected first, followed by deltaC and deltaD, and finally by another hairy/Enhancer of split-related gene her7. In situ hybridization with an intron-specific her1 probe indicates that transcriptional bursts of expression are normal in tor mutants, suggesting that tor regulates her1 at the post-transcriptional level. Despite defects in Notch pathway gene expression, somite boundaries form normally in tor mutant embryos, although defects are apparent later when somitic cells mature to form muscle fibers. Thus the tor mutant phenotype suggests that precise oscillations of Notch pathway transcripts are not essential for establishing segmental pattern in the PSM.
Errata / Notes
Ph.D. Thesis, University of California, Berkeley
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping