AUTHOR=Zhang Sushan , Choi Hyuk Su , Jung Han-Sung , Lee Jong-Min 

TITLE=FGF10 Is Required for Circumvallate Papilla Morphogenesis by Maintaining Lgr5 Activity

JOURNAL=Frontiers in Physiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2018.01192

DOI=10.3389/fphys.2018.01192

ISSN=1664-042X

ABSTRACT=<p>Taste buds develop in different regions of the mammal oral cavity. Adult stem cells in various organs including the tongue papillae are marked by leucine-rich repeat-containing G protein-coupled receptor 5 (<italic>Lgr5</italic>) and its homolog, <italic>Lgr6</italic>. Recent studies have reported that adult taste stem/progenitor cells in circumvallate papilla (CVP) on the posterior tongue are <italic>Lgr5</italic>-positive. In this study, we confirm the <italic>Lgr5</italic> expression pattern during CVP development. A previous study reported that mesenchymal <italic>Fgf10</italic> is necessary for maintaining epithelial <italic>Lgr5</italic>-positive stem/progenitor cells. To confirm the interaction between <italic>Lgr5</italic>-positive CVP epithelium and mesenchymal factor FGF10, reverse recombination (180-degree) was performed after tongue epithelium detachment. FGF10 protein-soaked bead implantation was performed after reverse recombination to rescue CVP development. Moreover, we reduced mesenchymal <italic>Fgf10</italic> by BIO and SU5402 treatment which disrupted CVP morphogenesis. This study suggests that the crosstalk between epithelial <italic>Lgr5</italic> and mesenchymal <italic>Fgf10</italic> plays a pivotal role in CVP epithelium invagination during mouse tongue CVP development by maintaining <italic>Lgr5</italic>-positive stem/progenitor cells.</p>