title: RS and RGG repeats as primitive proteins at the transition between the RNA and RNP worlds.
abstract: For many experimental biologists in the field of nuclear cell biology, low complexity repeats in nuclear proteins constitute a nuisance. They are difficult to express, impossible to crystalize and have low but near ubiquitous unwanted affinities toward many biomolecules. Examples of such nuclear protein repeats are RS (Arg-Ser) repeats in splicing factors, RGG (Arg-Gly-Gly) repeats in hnRNP proteins and FG (Phe-Gly) repeats in nuclear pore components. Here, I would like to present a more positive perspective for at least a subset of repeats and suggest that they are excellent candidates to have constituted the first proteins emerging from an RNA world.
authors: Department of Biochemistry, Erasmus MC, Rotterdam, The Netherlands. m.fornerod@erasmusmc.nl
authors: Maarten
authors: M
authors: Fornerod
mesh_terms: D019418:Evolution, Chemical; D000069497:Origin of Life; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism*; D020449:Repetitive Sequences, Amino Acid / Q000502:physiology*; D012261:Ribonucleoproteins / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D012261:Ribonucleoproteins; D012313:RNA