Craniofacial Developmental Atlas of Protein Expression of the House Finch

Expression of FGF8 across the house finch beak at stages HH29/30, HH32, HH36, HH39 and HH42.

HH29/30

FGF8 expression at HH29/30

FGF8 (brown stain) is weakly expressed in (2) both the cytoplasm and nucleus at half of the upper jaw and across the whole lower jaw with (1) medium and low nuclear expression in the mesenchyme and medium cytoplasmic and nuclear expression in the epithelium at the tip of the upper jaw and (5) no expression at the outer edge of the lower jaw. (3) Low nuclear expression in cell condensation and (4) medium cytoplasmic and nuclear expression in potential myogenic area. Scale bars are 50µm. See expression of all proteins at stage HH29/30 here.

HH32

FGF8 expression at HH32

FGF8 (brown stain) mainly shows weak nuclear expression in the mesenchyme while both cytoplasmic and nuclear expression in the epithelium. Medium cytoplasmic and nuclear expression in (1) mesenchyme next to the retina, (2) terminus of the large condensation at the maxillary prominence and (3) developing muscle next to cartilage area. (2) Medium nuclear expression at the tip of the upper jaw. (4) Medium nuclear expression surrounding cell condensation with additional cytoplasmic expression. (5) Basihyal cartilage with low nuclear expression, perichondrogenic area with low cytoplasmic and nuclear expression. Developing muscle above with medium cytoplasmic and nuclear expression. (6) Cell condensation preceding Meckel's cartilage with low cytoplasmic and nuclear expression. Scale bars are 50µm. See expression of all proteins at stage HH32 here.

HH36

FGF8 expression at HH36

FGF8 (brown stain) shows overall weak cytoplasmic and nuclear expression while showing only nuclear expression at the tip. (1) Low nuclear expression in developing nasal cartilage and blood cells with high cytoplasmic and nuclear expression. (2) Weak cytoplasmic and nuclear expression in epithelium surrounding nasal cavity and nasal epithelium with combination of weak and strong nuclear expression in adjacent developing cartilage. (3) Low and high nuclear expression in developing premaxillary cartilage. (4) Developing cartilage with strong cytoplasmic and nuclear expression while surrounding muscle and mesenchyme show weak expression. (5) Developing salivary glands. (6) Strong nuclear expression in Meckel's cartilage with weak nuclear to nuclear and cytoplasmic expression in surrounding mesenchyme. Scale bars are 50µm. See expression of all proteins at stage HH36 here.

HH39

FGF8 expression at HH39

FGF8 (brown stain) shows weak cytoplasmic and nuclear expression with only nuclear expression at the tip. (1) Nasal conchae with weak cytoplasmic and nuclear expression, strong nuclear expression in nasal cartilage and low nuclear expression in surrounding mesenchyme. (2) Moderate cytoplasmic and nuclear expression in emerging osteogenic region and low nuclear expression in adjacent mesenchyme. (3) Premaxillary cartilage with low nuclear expression, perichondrogenic area shows strong expression and moderate expression in subjacent mesenchyme. (4) Weak to moderate expression in mesenchyme. (5) Strong nuclear expression in Meckel's cartilage and moderate cytoplasmic and nuclear expression in emerging osteogenic region. (6) Basihyal cartilage and surrounding mesenchyme shows weak cytoplasmic and nuclear expression. Scale bars are 50µm. See expression of all proteins at stage HH39 here.

HH42

FGF8 expression at HH42

FGF8 (brown stain) is weakly expressed in the cytoplasm across the upper and lower jaw. (1) Strong nuclear expression in cartilage with no expression in osteogenic area and weak cytoplasmic expression in periosteogenic area and mesenchyme. (2) Moderate cytoplasmic and nuclear expression in epithelium but no expression in overlaying mesenchyme. (3) Blood cells with high cytoplasmic and nuclear expression. (4) No expression in paraglossal cartilage with strong nuclear expression in cartilage edges. (5) Weak cytoplasmic expression in dermal condensations, mesenchyme and muscle with medium cytoplasmic and nuclear expression in epithelium. (6) Meckel's cartilage shows strong nuclear expression but no expression in cartilage edges and osteogenic region. Periosteogenic region with moderate cytoplasmic and nuclear expression. Scale bars are 50µm. See expression of all proteins at stage HH42 here.