GSE125725
RNA-seq and ribosome profiling of heat shocked wild type and Mettl14 -/- mouse embryonic stem cells
N6-methyladenosine (m6A) is a dynamic and reversible nucleotide modification in mRNA. m6A alters mRNA fate, but it is unclear why the effects of m6A can vary in different cellular contexts. Here we show that methylated mRNAs are catalysts for liquid-liquid phase separation of the YTHDF family of m6A-binding proteins. RNAs that contain multiple, but not single, m6A residues recruit multiple YTHDF proteins, causing them to undergo a proximity-induced phase separation. YTHDF proteins show liquid-like properties upon binding polymethylated mRNAs in cells, and partition into endogenous phase-separated compartments, such as P-bodies, neuronal RNA granules, and stress granules. The complexes of YTHDF proteins and polymethylated mRNAs are targeted to different compartments depending on the cell context, leading to different effects on m6A mRNAs. These studies reveal a role for nucleotide modifications in regulating phase separation and indicate that the cellular properties of m6A-modified mRNAs can be explained by liquid-liquid phase separation principles. Overall design: RNA-seq was performed on wild type and Mettl14 -/- mouse embryonic stem cells. Four replicates were sequenced under non-stressed conditions, after heat shock at 42°C for 30 min, and 1 h after recovery from heat shock stress.