Potassium Channel Tetramerisation Domain Containing Protein 15 (KCTD15)

Kctd15 is a factor expressed in the NPB that efficiently inhibits NC induction in zebrafish and frog embryos. Whereas overexpression of Kctd15 inhibited NC formation, knockdown of Kctd15 led to expansion of the NC domain. Likewise, NC induction by Wnt3a plus Chordin in Xenopus animal explants was suppressed by Kctd15, but constitutively active β-catenin reversed Kctd15-mediated suppression of NC induction. Suppression of NC induction by inhibition of Wnt8.1 was rescued by reduction of Kctd15 expression, linking Kctd15 action to the Wnt pathway. Kctd15 inhibits NC formation by attenuating the output of the canonical Wnt pathway, thereby restricting expansion of the NC domain beyond its normal range.