Can I read Fragile X (CGG)n repeats induce a transcriptional repression in cis upon a linked promoter: evidence for a chromatin mediated effect on EtoBox?

Fragile X (CGG)n repeats induce a transcriptional repression in cis upon a linked promoter: evidence for a chromatin mediated effect by Simon P Chandler; Pushpa Kansagra; Mark C Hirst is a Biochemistry, Genetics and Molecular Biology article available to read on EtoBox.

What is Fragile X (CGG)n repeats induce a transcriptional repression in cis upon a linked promoter: evidence for a chromatin mediated effect about?

## Background: Expansion of an unstable (cgg)n repeat to over 200 triplets within the promoter region of the human fmr1 gene leads to extensive local methylation and transcription silencing, resulting in the loss of fmrp protein and the development of the clinical features of fragile x syndrome. the causative link between (cgg)n expansion, methylation and gene silencing is unknown, although gene silencing is associated with extensive changes to local chromatin architecture. ## Results: In order to determine the direct effects of increased repeat length on gene transcription in a chromatin context, we have examined the influence of fmr1 (cgg)n repeats upon transcription from the hsv thymidine kinase promoter in the xenopus laevis oocyte. we observe a reduction in mrna production directly associated with increasing repeat length, with a 90% reduction in mrna production from arrays over 100 repeats in length. using a kinetic approach, we show that this transcriptional repression is concomitant with chromatin maturation and, using in vitro transcription, we show that chromatin formation is a fundamental part of the repressive pathway mediated by (cgg)n repeats. using trichostatin a, a

Who reads Fragile X (CGG)n repeats induce a transcriptional repression in cis upon a linked promoter: evidence for a chromatin mediated effect?

Author

Simon P Chandler; Pushpa Kansagra; Mark C Hirst

Publisher

BioMed Central; Springer (Biomed Central Ltd.); London: BioMed Central, [2000]-; Springer Science and Business Media LLC (ISSN 1471-2199)

Published

2003

Language

EN

Field

Biochemistry, Genetics and Molecular Biology (Life Sciences)