“…Furthermore, overexpression of NKD paralogs can antagonize both canonical and non-canonical Wnt signal transduction in fish and frog embryos (Hu et al, 2010;Marsden et al, 2018;Van Raay et al, 2007;Yan et al, 2001), while depletion of Nkd1 and Nkd2 in early zebrafish embryos results in hyperactivation of canonical Wnt target genes. In addition, Nkd1 depletion produces non-canonical defects in left-right asymmetry signaling (Marsden et al, 2018;Schneider et al, 2010), exacerbates convergent extension defects under certain conditions (Van Raay et al, 2007) and sensitizes embryos to hyperactive Wnt signaling (Agonin and Van Raay, 2013). Curiously, in the light of these defects caused by Naked/NKD loss in fly and fish embryos, Nkd does not appear to be essential in mice: five doubleknockout mice were bread from heterozygous parents, although these were born at sub-Mendelian ratios, and with subtle bone abnormalities reminiscent of Axin2-deficient mice .…”