VIRMA-mediated m⁶A modification regulates forebrain formation through modulating ribosome biogenesis.

Area of Science:

• Molecular Biology
• Developmental Biology
• Epigenetics

Background:

• N-Methyladenosine (m6A) modification is crucial for tissue development and homeostasis.
• The precise mechanisms of m6A cellular adaptation and its impact on protein synthesis are not fully understood.
• VIRMA, a core component of the m6A methyltransferase complex, is highly expressed in the embryonic brain and cancers.

Purpose of the Study:

• To investigate the role of VIRMA-mediated m6A modification in ribosome biogenesis and cellular adaptation.
• To elucidate the impact of VIRMA on neural progenitor/stem cell proliferation, apoptosis, and brain development.
• To explore the conservation of this mechanism in cancer cells.

Main Methods:

• Depletion of VIRMA in neural progenitor/stem cells.
• Assessment of m6A levels and ribosome biogenesis.
• Analysis of cell proliferation, apoptosis, and forebrain development.
• Investigation of mRNA decay pathways and p53-dependent stress response.

Main Results:

• VIRMA depletion destabilized the m6A writer complex, reduced m6A levels, and impaired ribosome biogenesis.
• This led to decreased neural progenitor/stem cell proliferation, increased apoptosis, and severe forebrain developmental defects.
• Mechanistically, VIRMA depletion inhibited mRNA decay, triggered a p53-dependent stress response, and compromised global protein synthesis.
• Similar effects were observed in some cancer cells, suggesting conserved mechanisms.

Conclusions:

• VIRMA-mediated m6A modification is essential for active ribosome biogenesis and normal brain development.
• The study reveals a critical role for m6A in adapting the protein synthesis machinery during embryonic development.
• The findings highlight a conserved mechanism with implications for both developmental biology and cancer research.