Unravelling the induction and development of intramembranous bones in the chicken eye

Abstract

Bone development is a complex process, involving multiple tissues and hierarchical inductive interactions. The study of skeletal development has focused on endochondral bones while intramembranous bones (e.g. scleral ossicles) have received less attention. Although, sonic hedgehog was recently demonstrated to be present during induction of scleral ossicles, other signalling molecules are still unknown. Using in situ hybridization and bead implantation I have demonstrated the presence or absence and the involvement of candidate genes and gene families during the development of scleral ossicles. Scleraxis, patched, as well as the bone morphogenetic protein (BMP) family of genes, were found to be involved in the development of scleral ossicles. Conversely, it was determined that indian hedgehog and msx2 are not present. This study has contributed to unravelling the signals involved during the induction and subsequent development of scleral ossicles and has contributed to the current understanding of intramembranous bone development.