METTL3

METTL3, or Methyltransferase-Like 3, is a human gene that encodes a catalytic subunit of the N6-methyladenosine (m6A) methyltransferase complex. m6A is the most prevalent internal modification in eukaryotic messenger RNA (mRNA) and plays a crucial role in regulating various aspects of RNA metabolism, including RNA splicing, export, translation, and degradation.

METTL3 acts as the core methyltransferase, responsible for catalyzing the addition of a methyl group to the adenine base at the N6 position. It forms a stable heterodimer with METTL14, another key component of the m6A methyltransferase complex. This heterodimer provides structural stability and facilitates the interaction with RNA substrates. The complex also includes other proteins, such as WTAP (Wilms Tumor 1-Associating Protein), which recruits the complex to specific RNA targets.

The m6A modification mediated by METTL3 influences gene expression at multiple levels. It can affect mRNA stability, leading to either increased or decreased transcript levels. It can also regulate the efficiency of translation by influencing ribosome loading and protein synthesis. Furthermore, m6A can modulate RNA splicing patterns, leading to the production of different protein isoforms.

Dysregulation of METTL3 expression or activity has been implicated in various human diseases, including cancer. In some cancers, METTL3 is upregulated and promotes tumor growth and metastasis. In other cancers, METTL3 may act as a tumor suppressor. Its specific role can vary depending on the cancer type and cellular context. METTL3 is also involved in other biological processes, such as development, immunity, and neuronal function. Research into METTL3 and m6A modification is ongoing and continues to reveal new insights into their roles in health and disease.