<i>Grem1</i> expression during mouse craniofacial development.

<p>(<b>A-E</b>) Expression of <i>Grem1</i> is visualized by X-Gal staining of heterozygous <i>Grem1</i>^<i>LacZ</i> whole mount embryos. (<b>A</b>) At E11.5, <i>Grem1</i> is expressed in the dorsal part of the lateral nasal prominence (lnp). Stippled lines demarcate the nasal pits. (<b>B</b>) At E12.5, <i>Grem1</i>-positive domains are also detectable in the merging zones (arrowheads) of medial nasal prominences (mnp) and maxillary prominences (mxp). (<b>C-G</b>) Secondary palate development. (<b>C</b>) At E13.5, <i>Grem1</i>-positive domains are observed in the forming soft palate (sp). (<b>D</b>) At E14.5, the hard palate (hp) has formed while the <i>Grem1</i>-expressing shelves of the soft palate are not yet fused. (<b>E</b>) At E15.5, the soft palate has fused and <i>Grem1</i> expression extends posterior to the pharynx (ph). Note the sharp anterior boundary of <i>Grem1</i> expression in the soft palate (arrowheads). (<b>F, G</b>) Sections of whole mount stained embryos. (<b>F</b>) Cross section at the level indicated in (D) showing that <i>Grem1</i> expression is restricted to the mesenchyme. (<b>G</b>) Cross section at the level indicated in (E) showing <i>Grem1</i> expression in the soft palate, which separates the nasopharynx (np) from the oral cavity (oc). Additional abbreviations: a, anterior; l, lateral; m, medial; mdp, mandibular prominence; p, posterior. Scale bars: 500μm.