xSuv4-20h1/h2 enzymatic activity is required in the ectodermal germ layer.

<p>(A, D) Schematic illustrations of targeting microinjections into mesendodermal or ectodermal territories at 8-cell stage. (B) Injecting xSuv4-20h MOs into the mesendoderm causes no apparent morphological phenotype in the embryo. (C) Neural, mesodermal and endodermal marker genes are expressed normally. (E) xSuv4-20h MOs reduce eyes, cranial and trunk melanophores, when injected into the ectoderm. (F) Expression of all tested markers in mesoderm and endoderm is normal, except for Delta-like 1, whose expression specifically in the open neural plate is strongly reduced on the injected side. Global morphology was assessed at hatching stage (NF36), molecular markers at indicated stages during neurulation. Top row images in (B) and (E) depict whole embryos for overview.