Display Settings:


Send to:

Choose Destination
See comment in PubMed Commons below
Hum Mol Genet. 2004 Mar 1;13(5):495-507. Epub 2004 Jan 13.

Muscleblind protein, MBNL1/EXP, binds specifically to CHHG repeats.

Author information

  • 1Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo, Japan.


Myotonic dystrophy (DM) type 1 is caused by an expansion of a CTG repeat in the DMPK gene and type 2 by a CCTG repeat in the ZNF9 gene. Previous reports have suggested that transcripts containing expanded CUG/CCUG repeats might have toxic gain-of-function effects, probably affecting the function of RNA-binding proteins in the pathogenesis of DM. Here, it was attempted to compare the RNA-binding properties of three proteins, CUG-BP, MBNL1/EXP and PKR, which have previously been suggested to interact with CUG repeats. MBNL1, but not CUG-BP or PKR, interacted with both CUG and CCUG repeats in a yeast three-hybrid system. By using various synthetic RNAs, it was found that MBNL1 specifically interacts with repetitive sequences summarized as CHHG and CHG repeats, where H is A, U or C. Interestingly, MBNL1 did not interact with a genuine double-stranded RNA comprising CAG/CUG repeats, suggesting that MBNL1 prefers bulge-containing double-stranded RNAs. Deletion analysis indicates a difference in RNA-binding abilities among splice variants of MBNL1. It was also found that MBNL1 can bind to repetitive motifs in ZNF9, which contain a minimal length of CCUG repeats with non-CCUG insertions.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk