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bioRxiv · 10.1101/295709

Secondary neurulation-fated cells in the tail bud undergo self-renewal and tubulogenesis regulated by a Sox2 gradient

Kawachi, T.·Shimokita, E.·Tadokoro, R.·Takahashi, Y.
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Abstract

During amniote development, anterior and posterior components of the neural tube form by primary neurulation (PN) and secondary neurulation (SN), respectively. Unlike PN, SN proceeds by the mesenchymal-to-epithelial transition of SN precursors in the tail bud, a critical structure for the axial elongation. Our direct cell labeling delineates non-overlapping territories of SN- and mesodermal precursors in the chicken tail bud. SN-fated precursors are further divided into self-renewing and differentiating cells, a decision regulated by graded expression levels of Sox2. Whereas Sox2 is confined to SN precursors, Brachyury (T) is widely and uniformly distributed in the tail bud, indicating that Sox2+/Brachyury+ cells are neural-fated and not mesodermal. These results uncover multiple steps during the neural posterior elongation, including precocious segregation of SN precursors, their self-renewal, and regulation by graded Sox 2.

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Kawachi, T., Shimokita, E., Tadokoro, R., Takahashi, Y.. 2018-04-05. Secondary neurulation-fated cells in the tail bud undergo self-renewal and tubulogenesis regulated by a Sox2 gradient. https://doi.org/10.1101/295709

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