title: Lost once, the Fragile X Mental Retardation protein is now back onto brain polyribosomes.
abstract: The Fragile X Mental Retardation protein (FMRP) is an RNA-binding protein and its absence leads to the Fragile X syndrome, the most common form of inherited mental retardation. Because it has been acknowledged for a long time that FMRP is associated with polyribosomal mRNPs in all non-neuronal cellular systems studied so far, it is thought that it regulates translation in neurons also; however, its exact function remains elusive. Recently, it has been reported that, contrary to non-neuronal cells, brain FMRP is not associated with the translation machinery, but is part of repressed small RNP complexes excluded from polyribosomes.(27) To elucidate this puzzling result, Stefani et al.(17) and Khandjian et al.(32) have optimized methods to analyze brain polyribosomes and now provide definitive evidence for the association of FMRP with brain polyribosomes. In addition, the data presented in these two reports clearly indicate that FMRP's function resides at the translation control level.
authors.affiliation: Unité de Recherche en Génétique Humaine et Moléculaire, Centre de recherche Hôpital Saint-François d'Assise, le CHUQ, Québec, Canada.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Davidovic
authors.forename: Marc-Etienne
authors.initials: ME
authors.lastname: Huot
authors.forename: Edouard W
authors.initials: EW
authors.lastname: Khandjian
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D004330:Drosophila; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000378:metabolism*; D005600:Fragile X Syndrome / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D009474:Neurons / Q000166:cytology; D011132:Polyribosomes / Q000378:metabolism*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D012261:Ribonucleoproteins / Q000378:metabolism
chemical_list: D051860:Fragile X Messenger Ribonucleoprotein 1; D012333:RNA, Messenger; D012261:Ribonucleoproteins