RNA sequencing of CDH1+/THY1+ and CDH1-/THY1+ germline stem cells

To futher understand the properties of CDH1+ GSCs and CDH1- GSCs, flow cytometry was used to sort the twopopulations after trypsin digestion and they were compared by total RNA sequencing (RNA-seq). The data clearlyshowed CDH1+ and CDH1- cells as having highly distinct profiles. In particular, numerous epithelial genes (e.g.Dsp, Pkp2, Krt19) were highly expressed in the CDH1+ population. In contrast, most genes known to be generalmarkers of SSCs/undifferentiated spermatogonia were downregulated (e.g. GFRA1 and ID4) or unchanged (e.g. ZBTB16and SALL4) in CDH1- GSCs. Additionally, KEGG pathway analysis revealed that the two populations exhibiteddistinctive activity in several signaling pathways including WNT and TGFb signaling. Notably, Tgfbr1, Smad2, Smad3tended to be lower in CDH1+ GSCs while Smad7, an inhibitor of TGFb signaling, was higher.The results showed thatCDH1+ GSCs were more epithelial in nature compared to CDH1- GSCs and supported the notion that CDH1+ GSCs are areable to partly overcome MET barrier because they may be in an advanced stage of MET. Overall design: Examination of RNA levels in CDH1+/THY1+ and CDH1-/THY1+ GSCs.

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An J, Zheng Y, Dann CT