As tbx1 was expressed in both the pharyngeal endoderm and mesoderm (Fig. 2A; supplementary material Fig. S2A-C) (Piotrowski et al., 2003), we investigated the requirements of Tbx1 in each tissue for pouch morphogenesis.
A 454-cDNA-library of the potbellied seahorse yielded 36 MHIIβ sequences (23 from pregnant pouch tissue (normalized/unnormalized: 18/5), 5 from non-pregnant pouch tissue (2/3), and 8 from normalized reference tissues) which could be assembled into a single contig identical to the MHIIβ genomic DNA sequence.
Extensive mucositis occurred in all of the untreated animals, and consisted of severe damage to cheek pouch tissues (epithelium, underlying connective tissue, and muscle bundles).
Fig. 6 H&E stained dysplastic hamster cheek pouch tissue topically administered with acid-disassembling Au NCs (a) and normal hamster cheek pouch tissue (b).
The expression of MHIIβ in pouch tissue of H. abdominalis males suggests that MH molecules may be immunologically active in brood-pouch tissues, and could possibly play a role in immune protection during the development of embryos in the paternal brood pouch [ 36].
In addition, no adverse effects (e.g., inflammation) from the Au NCs were observed in either cheek pouch tissue sample, implying high biocompatibility of the administration methods.
As shown in Fig. 5b and Additional file 1: Figure S1, the pH in the DMBA-applied cheek pouch tissue was determined to be mildly acidic (approximately 6.2), while the pH in the mineral oil-applied cheek pouch tissue was found to be close to a normal physiological condition (approximately 7.3).
This observation implies that patristacin may have initially evolved in conjunction with the liver/kidney then added a new tissue (the brood pouch) to its repertoire with very little change to its original structure (demonstrated by molecular analysis) and function.
