RNA 5-methylcytosine regulates YBX2-dependent liquid-liquid phase separation

Area of Science:

• Molecular Biology
• Epigenetics
• RNA Biology

Background:

• 5-Methylcytosine (m⁵C) is a prevalent internal modification in eukaryotic messenger RNA (mRNA).
• RNA modifications play crucial roles in gene regulation and cellular processes.
• Liquid-liquid phase separation (LLPS) is an emerging mechanism for organizing cellular components.

Purpose of the Study:

• To identify novel mammalian m⁵C binding proteins.
• To investigate the role of Y box protein 2 (YBX2) in m⁵C RNA interactions.
• To elucidate the relationship between RNA m⁵C modification and LLPS.

Main Methods:

• Biochemical assays to identify m⁵C binding proteins.
• In vivo and in vitro studies of YBX2.
• Liquid-liquid phase separation (LLPS) experiments.
• Crystal structure analysis of YBX2.

Main Results:

• Y box protein 2 (YBX2) was identified as a novel mammalian m⁵C binding protein.
• YBX2 undergoes liquid-liquid phase separation (LLPS) both in vivo and in vitro.
• m⁵C marked RNA enhances YBX2-dependent LLPS.
• The W100 residue in YBX2 is a critical m⁵C binding site mediating phase separation.

Conclusions:

• YBX2 is a key regulator linking RNA m⁵C modification to LLPS.
• This interaction provides a new regulatory mechanism in epigenetics.
• Understanding YBX2-m⁵C-LLPS interactions offers insights into RNA biology and epigenetic regulation.