Expression of Wise in Chick Embryos

In the 2007 study by Shigetani and Itasaki, the expression pattern of the molecule Wise, which modulates the Wnt signaling pathway, was investigated during early chick embryogenesis using in situ hybridization. Wise was first detected in the ectoderm of late neurula stage embryos and later in the trunk ectoderm, pharyngeal arches, limb buds, and feather buds. It was also expressed in certain cartilages, such as those in the maxillary process and limbs, with increasing expression over time. The expression of Wise was found in areas where other signaling molecules like Wnt, Bmp, and Shh are active in morphogenesis and differentiation, suggesting a potential role for Wise in the development of these structures. Additionally, Wise expression was induced anteriorly in a mirror-symmetric manner when FGF8-soaked beads were implanted, leading to ectopic limb formation, and showed a complementary pattern to polarizing activity in limb buds. In the skin, Wise expression was first detectable ventral to the shoulder joint and formed a ring pattern around the presumptive feather bud, with down-regulation at the posterior side as feather buds elongated. These findings imply that Wise may have a similar role in feather development in chicks as it does in hair growth cycles in mammals.