Extended Data Figure 5: Outpocketing of POGD in bichir and secondary constriction of POGD in sturgeon pharyngulae during development.
From: Pre-oral gut contributes to facial structures in non-teleost fishes
a–c, Horizontal vibratome sections of bichir pharyngulae at three succeeding stages, showing formation of POGD and cement glands. Head to the left; white dotted line delineates POGD. Fibronectin (green) marks cell and tissue borders; actin (red) stains contracting actin fibres during POGD formation. Red arrowheads point to the possible role of actin cables in POGD outpocketing. d–f, Plastic parasagittal sections of sturgeon pharyngulae at three succeeding stages. Head to the left; stained with AzureB/eosin. Red dotted line delineates POGD. b, brain; h, heart; pog, pre-oral gut.
