Adenosine methylation as a molecular imprint defining the fate of RNA.

Multiple lines of evidence suggest the RNA modification N6 -methyladonsine (m6 A), which is installed in the nucleus cotranscriptionally and, thereafter, serves as a reversible chemical imprint that influences several steps of mRNA metabolism. This includes but is not limited to RNA folding, splicing, stability, transport and translation. In this Review we focus on the current view of the nuclear installation of m6 A as well as the molecular players involved, the so called m6 A writers. We also explore the effector proteins, or m6 A readers, that decode the imprint in different cellular contexts and compartments, and ultimately, the way the modification influences the lifecycle of an RNA molecule. The wide evolutionary conservation of m6 A and its critical role in physiology and disease warrants further studies into this burgeoning and exciting field.