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bioRxiv · 10.1101/2021.07.10.451887

TGFβ signalling is required to maintain pluripotency of human naïve pluripotent stem cells

Osnato, A.·Brown, S.·Krueger, C.·Andrews, S.·Collier, A. J.·Nakanoh, S.·Quiroga Londono, M.·Wesley, B. T.·Muraro, D.·Brumm, S.·Niakan, K.·Vallier, L.·Ortmann, D.·Rugg-Gunn, P. J.
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Abstract

The signalling pathways that maintain primed human pluripotent stem cells (hPSCs) have been well characterised, revealing a critical role for TGF{beta}/Activin/Nodal signalling. In contrast, the signalling requirements of naive human pluripotency have not been fully established. Here, we demonstrate that TGF{beta} signalling is required to maintain naive hPSCs. The downstream effector proteins - SMAD2/3 - bind common sites in naive and primed hPSCs, including shared pluripotency genes. In naive hPSCs, SMAD2/3 additionally bind to active regulatory regions near to naive pluripotency genes. Inhibiting TGF{beta} signalling in naive hPSCs causes the downregulation of SMAD2/3-target genes and pluripotency exit. Single-cell analyses reveal that naive and primed hPSCs follow different transcriptional trajectories after inhibition of TGF{beta} signalling. Primed hPSCs differentiate into neuroectoderm cells, whereas naive hPSCs transition into trophectoderm. These results establish that there is a continuum for TGF{beta} pathway function in human pluripotency spanning a developmental window from naive to primed states.

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Osnato, A., Brown, S., Krueger, C., Andrews, S., Collier, A. J., Nakanoh, S., Quiroga Londono, M., Wesley, B. T., Muraro, D., Brumm, S., Niakan, K., Vallier, L., Ortmann, D., Rugg-Gunn, P. J.. 2021-07-11. TGFβ signalling is required to maintain pluripotency of human naïve pluripotent stem cells. https://doi.org/10.1101/2021.07.10.451887

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