Expression of osteoblastic and osteoclastic genes during spontaneous regeneration and autotransplantation of goldfish scale: A new tool to study intramembranous bone regeneration

► Goldfish scale regeneration shares similarities in gene expression and morphology with intramembranous bone regeneration. ► During scale regeneration, osteoblastic genes; dlx5, osterix, collagen, ALP, and osteocalcin, show similar patterns of expression as intramembranous bone regeneration. ► Dlx5 is expressed in the early stage of scale regeneration. ► Loss of correct cell-to-cell contact between the scale-pocket and the scale cortex triggers scale resorption and regeneration. ► Scale regeneration starts and finishes in the area that lacks cell-to-cell contact; U-shape trimmed/circular-hole perforated part, of transplanted scales.