RGG/RG Motif Regions in RNA Binding and Phase Separation

J Mol Biol. 2018 Nov 2;430(23):4650-4665. doi: 10.1016/j.jmb.2018.06.014. Epub 2018 Jun 15.


RGG/RG motifs are RNA binding segments found in many proteins that can partition into membraneless organelles. They occur in the context of low-complexity disordered regions and often in multiple copies. Although short RGG/RG-containing regions can sometimes form high-affinity interactions with RNA structures, multiple RGG/RG repeats are generally required for high-affinity binding, suggestive of the dynamic, multivalent interactions that are thought to underlie phase separation in formation of cellular membraneless organelles. Arginine can interact with nucleotide bases via hydrogen bonding and π-stacking; thus, nucleotide conformers that provide access to the bases provide enhanced opportunities for RGG interactions. Methylation of RGG/RG regions, which is accomplished by protein arginine methyltransferase enzymes, occurs to different degrees in different cell types and may regulate the behavior of proteins containing these regions.

Keywords: GAR; asymmetric dimethylation; intrinsically disordered; phase separation; ribonucleoprotein granules.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Motifs
  • Arginine / metabolism
  • Binding Sites
  • Hydrogen Bonding
  • Methylation
  • Models, Molecular
  • Molecular Conformation
  • Organelles / chemistry
  • Organelles / metabolism
  • Phase Transition
  • RNA / chemistry*
  • RNA / metabolism*
  • RNA-Binding Proteins / chemistry*
  • RNA-Binding Proteins / metabolism*


  • RNA-Binding Proteins
  • RNA
  • Arginine