593A Poster - 08. Patterning, morphogenesis and organogenesis
Thursday April 07, 2:00 PM - 4:00 PM

Authors:
Annabel May; Katja Röper

Affiliation: MRC LMB

Keywords:
n. tissue specification; p. single cell sequencing

Many internal organs are composed of epithelial tubes, the morphogenetic effectors responsible for controlling morphogenesis in these tubes and their order of action is yet to be comprehensively assessed. Within our tubulogenesis model, the Drosophila embryonic salivary gland, morphogenetic effectors have previously been identified either individually, as a result of mutant phenotypes and whole embryo microarrays or systematically, though gain of function screens. Currently there has been no attempt to assess the entire transcriptional landscape of the developing Drosophila melanogaster embryonic salivary gland.

Using a combinatorial method of strictly staged embryos, fluorophore driven embryo cell sorting and 10x chromium single cell sequencing we describe two new stage 11 embryonic single cell sequencing data sets. A comprehensive cell lineage of the embryonic salivary gland, central nervous system and muscular cells driven by the transcription factor forkhead covering developmental time points of salivary gland specification, invagination and migration and a second dataset at an identical time point isolating epithelial cells expressing the Drosophila homologue of Beta-Catenin, Armadillo.

Here we present both data sets as a spatiotemporal specific bioinformatic tool to identify and investigating genes involved in salivary gland development. Following bioinformatic labelling of the two cell populations we employed differential expression analysis. This technique alone yielded well-known salivary gland markers and a number of novel genes not previously implicated in salivary gland development. These genes include salivary gland specific and early expressed transcription factors, highly up-regulated genes within the developed salivary gland, genes specifically excluded from the salivary gland compared to surrounding epithelia, and a number of as-yet uncategorised genes.
Further investigation into the forkhead driven cell population using pseudotime and marker based identification provided a useful tool for prediction of temporal based expression across salivary gland development. This technique again successfully identified both well-known genes and genes previously not described to be temporally expressed within the salivary gland. This specific dataset has lead to the identification of novel gene expression patterning within the early salivary gland, identification of temporally controlled expression of adhesion molecules in time with morphogenetic movement of the tissue and highlighted upregulation of secretory machinery far earlier than previously reported.