1. Department of Cell Biology, Medical School, University of Utrecht (A.M.M.v.P., D.G.d.R.), Utrecht, The Netherlands;
2. Netherlands Institute for Developmental Biology, Hubrecht Laboratory (B.v.d.B., P.T.v.d.S.), Utrecht, The Netherlands;
3. Center for Biotechnology and Department of Medical Nutrition, Karolinska Institute (J.-Å.G., G.G.J.M.K.), Huddinge, Sweden