Fin ray branching is defined by TRAP+ osteolytic tubules in zebrafish

João Cardeira-Da-Silva, Anabela Bensimon-Brito, Marco Tarasco, Ana S. Brandão, Joana T. Rosa, Jorge Borbinha, Paulo J. Almeida, António Jacinto, M. Leonor Cancela, Paulo J. Gavaia, Didier Y.R. Stainier, Vincent Laizé

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The shaping of bone structures relies on various cell types and signaling pathways. Here, we use the zebrafish bifurcating fin rays during regeneration to investigate bone patterning. We found that the regenerating fin rays form via two mineralization fronts that undergo an osteoblast-dependent fusion/stitching until the branchpoint, and that bifurcation is not simply the splitting of one unit into two. We identified tartrate-resistant acid phosphatase-positive osteolytic tubular structures at the branchpoints, hereafter named osteolytic tubules (OLTs). Chemical inhibition of their bone-resorbing activity strongly impairs ray bifurcation, indicating that OLTs counteract the stitching process. Furthermore, by testing different osteoactive compounds, we show that the position of the branchpoint depends on the balance between bone mineralization and resorption activities. Overall, these findings provide a unique perspective on fin ray formation and bifurcation, and reveal a key role for OLTs in defining the proximo-distal position of the branchpoint.

Original languageEnglish
Article numbere2209231119
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number48
Publication statusPublished - 29 Nov 2022


  • bifurcation
  • bone patterning
  • bone resorption
  • fin regeneration
  • osteoclasts


Dive into the research topics of 'Fin ray branching is defined by TRAP+ osteolytic tubules in zebrafish'. Together they form a unique fingerprint.

Cite this