Fig. 3.

Fig. 3.

Histology and in situ hybridization on cryosections of catshark Scyliorhinus canicula skeletal tissues at stage 33. (A, B, C, V) Hematoxylin–Eosin–Saffron (HES) histological staining. (D–U) Expression of Col10a1 duplicates in developing teeth and scales of catshark detected with probes specific for each duplicate. Dotted lines indicate the mesenchymal compartment limits. Asterisk marks the mineralizing matrix, often seen as empty space due to decalcification. (W, X) Expression of Col10a1.4 duplicate in comparison to Col2a1 in mineralizing vertebral tissues of catshark. Black arrowhead in the neural arch points to the site of globular mineralization; open arrowhead points to the site of lamellar mineralization; black arrowhead in the vertebral body points to the site of fibrous mineralization. Scale bars: 50 µm (A–U), 200 µm (V–X). Abbreviations: mat. amel., maturation stage ameloblasts; M’s, Meckel’s cartilage; notoch, notochord; od., odontoblasts; sec. amel., secretory ameloblasts.