- The mother superior mutation ablates foxd3 activity in neural crest progenitor cells and depletes neural crest derivatives in zebrafish. Montero-Balaguer, M., Lang, M.R., Sachdev, S.W., Knappmeyer, C., Stewart, R.A., De La Guardia, A., Hatzopoulos, A.K., Knapik, E.W. Dev. Dyn. (2006)