Promoter-bound trinucleotide repeat mRNA drives epigenetic silencing in fragile X syndrome.

TitlePromoter-bound trinucleotide repeat mRNA drives epigenetic silencing in fragile X syndrome.
Publication TypeJournal Article
Year of Publication2014
AuthorsColak D, Zaninovic N, Cohen MS, Rosenwaks Z, Yang W-Y, Gerhardt J, Disney MD, Jaffrey SR
JournalScience
Volume343
Issue6174
Pagination1002-5
Date Published2014 Feb 28
ISSN1095-9203
KeywordsAnimals, Cell Line, DNA Methylation, Embryonic Stem Cells, Fragile X Mental Retardation Protein, Fragile X Syndrome, Gene Silencing, Humans, Mice, Mice, Inbred NOD, Mice, SCID, Neurons, Nuclear Proteins, Promoter Regions, Genetic, RNA, Messenger, RNA, Small Interfering, Trinucleotide Repeats
Abstract

Epigenetic gene silencing is seen in several repeat-expansion diseases. In fragile X syndrome, the most common genetic form of mental retardation, a CGG trinucleotide-repeat expansion adjacent to the fragile X mental retardation 1 (FMR1) gene promoter results in its epigenetic silencing. Here, we show that FMR1 silencing is mediated by the FMR1 mRNA. The FMR1 mRNA contains the transcribed CGG-repeat tract as part of the 5' untranslated region, which hybridizes to the complementary CGG-repeat portion of the FMR1 gene to form an RNA┬ĚDNA duplex. Disrupting the interaction of the mRNA with the CGG-repeat portion of the FMR1 gene prevents promoter silencing. Thus, our data link trinucleotide-repeat expansion to a form of RNA-directed gene silencing mediated by direct interactions of the trinucleotide-repeat RNA and DNA.

DOI10.1126/science.1245831
Alternate JournalScience
PubMed ID24578575
PubMed Central IDPMC4357282
Grant ListR01 MH80420 / MH / NIMH NIH HHS / United States
R01 NS056306 / NS / NINDS NIH HHS / United States
R21 NS087859 / NS / NINDS NIH HHS / United States
R01 GM079235 / GM / NIGMS NIH HHS / United States
R01 MH080420 / MH / NIMH NIH HHS / United States