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bioRxiv · 10.1101/2021.07.29.454253

m6A-mediated Cell-cell Communication Controls Planarian Regeneration

Abstract

Regeneration is the regrowth of damaged tissues or organs, a vital mechanism responding to damages from primitive organisms to higher mammals. Planarian possesses active whole-body regenerative capability owning to its vast reservoir of adult stem cells, neoblasts, thus provides an ideal model to delineate the underlying mechanisms for regeneration. N6-methyladenosine (m6A) regulates stem cell renewal and differentiation. However, how m6A controls regeneration at whole-organism level remains largely unknown. Here, we demonstrate that the depletion of m6A methyltransferase regulatory subunit wtap abolishes planarian regeneration, through regulating cell-cell communication and cell cycle. scRNA-Seq analysis unveils that the wtap knockdown induces a unique type of neural progenitor-like cells (NP-like cells), characterized by specific expression of the cell-cell communication ligand grn. Intriguingly, the depletion of m6A-modified transcripts grn/cdk9 (or cdk7) axis rescues the defective regeneration of planarian without wtap. Overall, our study reveals an indispensable role of m6A-dependent cell-cell communication essential for whole-organism regeneration.

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BibTeXRIS

Cui, G., Zhou, J.-Y., Ge, X.-Y., Sun, B.-F., Song, G.-G., Wang, X., Wang, X.-Z., Zhang, R., Wang, H., Jing, Q., Zhao, Y., Koziol, M., Zeng, A., Zhang, W., Han, D., Yang, Y., Yang, Y.-G.. 2021-07-29. m6A-mediated Cell-cell Communication Controls Planarian Regeneration. https://doi.org/10.1101/2021.07.29.454253

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