m6A Modification Regulates Planarian Regeneration [scRNA-seq]

Regeneration is the regrowth of damaged tissues or organs, a vital mechanism in response 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, providing an ideal model to delineate the underlying mechanisms for regeneration. RNA N6-methyladenosine (m6A) modification participates in many biological processes, including stem cell self-renewal and differentiation, in particular the regeneration of hematopoietic stem cells and axons. However, how m6A controls regeneration at the whole-organism level remains largely unknown. Here, we demonstrate that the depletion of m6A methyltransferase regulatory subunit wtap abolishes planarian regeneration, potentially through regulating genes related to cell-cell communication and cell cycle. Single-cell RNA-seq (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 caused by wtap knockdown. Overall, our study reveals an indispensable role of m6A modification in regulating whole-organism regeneration. Overall design: single cell RNA-seq of 5 samples from planarian at 0 hpa, 6 hpa, 3 dpa, 7 dpa and 11 dpa, and 5 samples from wtap knockdown planarian at 0 hpa, 6 hpa, 3 dpa, 7 dpa and 11 dpa.