Single cell RNA-sequencing of E11.5 Crect; ROSA26-lacZ mouse fusing upper lip and primary palate

Only mouse embryos that were positive for both Crect, an ectoderm specific Cre recombinase transgene, and the ROSA26 LacZ reporter allele were used for this study. Not that these mice are on a mixed genetic background. After isolation of E11.5 embryos with 45 somites, the face was isolated from the head using published procedures. Subsequently, the region of the upper face where the nasal and maxillary prominences are juxtaposed was microdissected out using forceps so that the region containing the lambdoid junction, the nasolacrimal groove, and the nasal fin were obtained. This tissue contained ectoderm and mesenchyme, as well as cells associated with blood vessels. Following dispersion into single cells by enzymatic and mechanical methods, cells were processed for single cell RNA sequencing using the 10X Genomics platform. Approximately 7000 cells were sequenced to a depth of 100,000 reads per cell.