High impact information on edn1

• This ectoderm also expresses ednrA1 in an edn1-dependent manner, suggesting that edn1 autoregulates its own expression [1].
• First we show that edn1-expressing cells in the first (mandibular) and second (hyoid) pharyngeal arch primordia are located most ventrally and surrounded by hand2-expressing cells [2].
• Next we show that along the DV axis of the early first arch primordia, bapx1 is expressed in an intermediate domain, which later marks the jaw joint, and this expression requires edn1 function. bapx1 function is required for formation of the jaw joint, the joint-associated retroarticular process of Meckel's cartilage, and the retroarticular bone [2].
• In addition, expression of eng2, normally restricted to first arch dorsal mesoderm, expands ventrally in hand2 and edn1 mutants [2].
• In zebrafish, endothelin 1 (edn1 or sucker) is required for formation of ventral cartilages and joints in the anterior pharyngeal arches of young larvae [2].

Biological context of edn1

• The recovery explains the less severe furinA mutant skeletal phenotype and suggests that late gene expression is dependent on a critical level of Edn1 signaling not present in the more severe edn1 mutants [3].

Anatomical context of edn1

• Knockdown of Ednra1 leads to fusions between upper- and lower-jaw cartilages, whereas the combined loss of Ednra1 and Ednra2 eliminates the lower jaw, similar to edn1(-/-) mutants. edn1 is expressed in pharyngeal arch ectoderm, mesoderm and endoderm [1].
• Collectively our results support a model for dorsoventral patterning of the gnathostome pharyngeal arches in which Et-1 in the environment of the postmigratory cranial neural crest specifies the lower jaw and other ventral arch fates [4].
• Later in development, suc/et-1 mutant embryos display defects in mesodermal and endodermal tissues of the pharynx [4].

Other interactions of edn1

• Similar to edn1, hand2 is required for ventral pharyngeal cartilage formation [2].

References