PUBLICATION
Pax9 drives development of the upper jaw but not teeth in zebrafish
- Authors
- Paudel, S., McLeod, S., Gjorcheska, S., Barske, L.
- ID
- ZDB-PUB-250501-8
- Date
- 2025
- Source
- Developmental Biology : (Journal)
- Registered Authors
- Barske, Lindsey, McLeod, Sarah
- Keywords
- Pax9, barbel, maxilla, premaxilla, zebrafish
- MeSH Terms
-
- Zebrafish*/embryology
- Zebrafish*/genetics
- PAX9 Transcription Factor*/genetics
- PAX9 Transcription Factor*/metabolism
- PAX9 Transcription Factor*/physiology
- Sp7 Transcription Factor
- Maxilla/embryology
- Tooth*/embryology
- Tooth*/metabolism
- Transcription Factors/metabolism
- Gene Expression Regulation, Developmental
- Mesoderm/embryology
- Mesoderm/metabolism
- Zebrafish Proteins*/genetics
- Zebrafish Proteins*/metabolism
- Osteoblasts/cytology
- Osteoblasts/metabolism
- Jaw*/embryology
- Animals
- Odontogenesis*/genetics
- Osteogenesis
- Neural Crest/embryology
- Neural Crest/metabolism
- PubMed
- 40306478 Full text @ Dev. Biol.
Citation
Paudel, S., McLeod, S., Gjorcheska, S., Barske, L. (2025) Pax9 drives development of the upper jaw but not teeth in zebrafish. Developmental Biology. :.
Abstract
Loss of dentition has occurred repeatedly throughout vertebrate evolution. Cyprinid fish, including zebrafish, form teeth only deep within the pharynx, not on their oral jaws. However, zebrafish still robustly express transcription factors associated with mammalian tooth development in the neural crest-derived mesenchyme surrounding the mouth. We investigated whether this expression is vestigial or whether these factors contribute to the formation of non-tooth mesenchymal structures in the oral region, using Pax9 as a test case. Zebrafish homozygous for two different pax9 mutant alleles develop the normal complement of pharyngeal teeth but fail to form the premaxilla bone, most of the maxilla, and nasal and maxillary barbels. Lack of most of the upper jaw complex does not preclude effective feeding in the laboratory environment. We observe a significant deficit of sp7:EGFP+ osteoblasts and adjacent alx4a:DsRed+ condensing mesenchyme around the maxilla, and no accumulation of either in the premaxillary domain. Loss of pax9 may prevent osteoprogenitors from maintaining the state of condensation required for full osteogenic differentiation. We conclude that Pax9 is not unequivocally required for all vertebrate tooth development but instead may be involved in the development of a variety of organs forming through mesenchymal condensation around the mouth.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping