METTL3-Dependent N6-Methyladenosine Modification Programs Human Neural Progenitor Cell Proliferation.

METTL3, a methyltransferase responsible for N6-methyladenosine (mA) modification, plays key regulatory roles in mammal central neural system (CNS) development. However, the specific epigenetic mechanisms governing human CNS development remain poorly elucidated. Here, we generated small-molecule-assisted shut-off (SMASh)-tagged hESC lines to reduce METTL3 protein levels, and found that METTL3 is not required for human neural progenitor cell (hNPC) formation and neuron differentiation. However, METTL3 deficiency inhibited hNPC proliferation by reducing expression. Mechanistic studies revealed that METTL3 degradation in hNPCs significantly decreased the enrichment of mA in mRNA, consequently reducing its expression. Our findings reveal a novel functional target (SLIT2) for METTL3 in hNPCs and contribute to a better understanding of mA-dependent mechanisms in hNPC proliferation.