Single cell transcriptomic analysis of endoderm derived cell lineages contribution in pituitary

Single cell transcriptomic analysis of pituitary gland from adult zebrafish that had specifically cells labeled with endoderm lineage by different strategies. The goal of this study is to examine the contribution of endoderm derived cell in the pituitary of vertebrate animals. We applied two strategies for labeling the endoderm derived cell in the pituitaries of zebrafish. The contribution of endoderm derived cells and the cell heterogeneity was later analyzed and resolved through constructing the single cell transcriptome through 10X Genomic pipeline. The first strategy is through endodermal lineage tracing techniques by Sox17 driven Cre recombinase conjuncted with an estrogen receptor (Sox17:CreERT2), which allows us to induce the conversion by addition of tamoxifen. We are able to identify the endoderm derived cell by microscopic observation with expression of mCherry gene from EGFP background. We made two single cell transcriptomic libraries by this strategy: the males library (file names started with M_Pituitary_Sox17creERUbiGtR) was derived by pooling 6 adult zebrafish pituitaries with moderate Sox17:CreERT2 conversion rate. The male1 library (file names started with M1_Pituitary_Sox17creERUbiGtR) was derived from the pituitary from a male zebrafish with high conversion rate. The second strategy is through transplant of taram-a mRNA injected GFP+ embryo to limit the cell into endoderm lineage. The treated embryonic cells were then injected into a BFP+ wild type embryo for tracing. The endoderm derived cells can be identify by expression of GFP. We made one single cell transcriptomic library by this strategy: the ubeGFP_transplanted (file names started with ubieGFP_Pit-Endo-transp) library was derived from pooling of pituitaries from adult transplanted fish.