head mesenchyme |
 |
not detected |
| | |
pharynx |
 |
strong |
| regional | Transcripts are present in abundance in the surrounding walls of the pharynx, posterior to the developing thyroid, but anterior to the lung bud. |
branchial arch |
 |
detected |
| regional | Hoxb1 transcripts are observed in the dorsal aspect of the second branchial arch unit, are no longer detected in the ventral aspect of the third branchial arch unit, and are now observed in the fourth. |
3rd branchial pouch |
 |
strong |
| regional | Transcripts are present in abundance in the caudal half of the third branchial cleft (surface ectoderm) and in the caudal half of the third pharyngeal pouch. |
3rd branchial groove ectoderm |
 |
strong |
| regional | Transcripts are present in abundance in the caudal half of the third branchial cleft (surface ectoderm) and in the caudal half of the third pharyngeal pouch. |
mesenchyme |
 |
weak |
| regional | Expression is also detected at lower levels in the lateral plate mesoderm (gut-associated mesoderm) near the third pouch. |