Pharyngeal pouch
Pharyngeal pouch
Definition
The pouches are polarized structures. For example, whereas the rostral half of each pouch expresses Bmp-7, the caudal half expresses FGF-8 and the dorsal aspect of each pouch is marked via its expression of Pax-1. each pouch has an individual sense of identity. Shh expression is a prominent early feature of the caudal endoderm of the second arch, and individual pouches mark the anterior limits of expression of Hox genes within the pharyngeal endoderm; Hox-a2 has a rostral boundary at the second pouch, Hox-a3 at the third pouch and Hox-a4 at the most caudal pouch[PMID:16313389]
Also known as branchial pouch, visceral pouch — per UBERON
The Pharyngeal pouch is a part of the Digestive.