A Gain-of-Function Mutation in Tnni2 Impeded Bone Development through Increasing Hif3a Expression in DA2B Mice
Figure 2
Tnni2 was expressed in chondrocytes and osteoblasts.
(A) In situ hybridization analyses with antisense Tnni2 riboprobe on histological sections of wild-type radii of E15.5 embryos showed that Tnni2 mRNA was expressed at the growth plates. Pink indicated Tnni2 mRNA signal (arrow). (B–G) Immunostaining analyses of tnni2 expression in growth plate. (B–C) tnni2 was expressed at chondrocytes (B, arrow) and osteoblasts (C, arrows) of the tibia growth plates from P8 wild-type mice. (D–F) The expression of tnni2 in the growth plates of radii and ulnae exhibited a spatial and temporal change. (D) In E15.5 wild-type embryos, tnni2 was expressed in pre-hypertrophic and hypertrophic chondrocytes (arrows). (E) At E17.5 wild-type embryos, tnni2 was mainly observed in proliferating chondrocytes (arrows). (F) At P6 wild-type radii, expression of tnni2 was in pre-hypertrophic, hypertrophic, immature proliferating and rest chondrocytes (arrows), whereas no discernible tnni2 was observed in mature proliferative chondrocytes. (G) Expression of tnni2 was in articular chondrocytes of tibiae of P12 wild-type mice (arrows). (H) tnni2 was observed in calvarial osteoblasts of P6 wild-type mice (arrows). (I) Negative staining for tnni2 protein. Scale bar, 100 µm (A–I). Embryonic day, E.