Sohail A, Nicoll O, Bendall AJ. Assessing candidate DLX-regulated genes in the first pharyngeal arch of chick embryos.
Dev Dyn 2025. [PMID:
39810614 DOI:
10.1002/dvdy.765]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2024] [Revised: 11/20/2024] [Accepted: 11/29/2024] [Indexed: 01/16/2025] Open
Abstract
BACKGROUND
Insights into the development and evolution of asymmetrical jaws will require an understanding of the gene regulatory networks that underpin the differential morphogenesis of the maxillary and mandibular domains of the first pharyngeal arch in a variety of gnathostomes. While a robust relationship has been demonstrated between jaw patterning and the Endothelin-Dlx gene axis, much less is known of the next level of genes in the jaw patterning hierarchy.
RESULTS
Several genes, whose expression depends on Dlx5 and/or Dlx6, have been identified in mice. Here, we examined the expression patterns of the chick orthologues of some of those genes, namely GSC, PITX1, HAND2, and GBX2, and tested their dependence on endothelin signaling to assess whether there is a conserved regulatory relationship between those genes in the chick embryo. To further validate these genes as direct DLX targets, we identified conserved non-coding sequences containing candidate DLX binding motifs and demonstrated DLX-responsiveness in vitro.
CONCLUSIONS
The evidence presented in this study combines to support the hypothesis that these four genes are direct targets of DLX transcription factors in the lower jaw-forming tissue.
Collapse