PUBLICATION
Patterning of cartilaginous condensations in the developing facial skeleton
- Authors
- Paudel, S., Gjorcheska, S., Bump, P., Barske, L.
- ID
- ZDB-PUB-220401-15
- Date
- 2022
- Source
- Developmental Biology 486: 44-55 (Journal)
- Registered Authors
- Barske, Lindsey
- Keywords
- Cartilage, Condensation, Pharyngeal arches, Zebrafish, barx1, sox9
- MeSH Terms
-
- Animals
- Cartilage/metabolism
- Chondrogenesis*/genetics
- Humans
- Mammals/metabolism
- PAX9 Transcription Factor
- Skull/metabolism
- Zebrafish*/metabolism
- Zebrafish Proteins/metabolism
- PubMed
- 35358504 Full text @ Dev. Biol.
Citation
Paudel, S., Gjorcheska, S., Bump, P., Barske, L. (2022) Patterning of cartilaginous condensations in the developing facial skeleton. Developmental Biology. 486:44-55.
Abstract
Adult endochondral bones are prefigured in the embryo as cellular condensations within fields of more loosely distributed skeletal progenitors. How these early condensations are initiated and shaped has remained enigmatic, despite the wealth of research on later stages of cartilage differentiation and endochondral ossification. Using the simple larval zebrafish facial skeleton as a model, we reevaluate the involvement of the master cartilage regulator Sox9 in shaping facial condensations and find it to be largely dispensable. We then use new lineage-tracing tools to definitively show that precartilaginous condensations originate from neighboring clusters of cells termed mesenchymal condensations. These cartilage-generating mesenchymal condensations express a cohort of transcription factors that are also expressed in odontogenic mesenchyme in mammals, including barx1, lhx6a/8a, and pax9. We hypothesized that the position of each mesenchymal condensation determines the axis of growth of its corresponding precartilaginous condensation, thus influencing its final shape. Consistent with this idea, we find that positive Fgf and inhibitory Jagged-Notch signals intersect to precisely position a mesenchymal condensation in the dorsal half of the second pharyngeal arch, with loss of pathway function leading to predictable shape changes in the resulting cartilage element. Deciphering the full array of signals that control the spatial distribution of mesenchymal condensations and regulate their maturation into precartilaginous condensations thus offers a promising approach for understanding the origins of skeletal form.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping