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Updated: May 17, 2026
09:20
Identification of RNA Fragments Resulting from Enzymatic Degradation using MALDI-TOF Mass Spectrometry
Published on: April 11, 2022
Triplet repeats in transcripts: structural insights into RNA toxicity.
Paulina Galka-Marciniak1, Martyna O Urbanek, Wlodzimierz J Krzyzosiak
1Laboratory of Molecular Biomedicine, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
Biological Chemistry
|October 12, 2012
Summary
Expanded triplet repeats in RNA transcripts cause genetic disorders. This review details their structural features and pathogenic mechanisms, including effects on splicing and RNA pathways.
Area of Science:
- Genetics
- Molecular Biology
- RNA Biology
Background:
- Tandem trinucleotide repeats in transcripts form RNA structures influenced by motif and reiteration.
- Normal triplet repeat functions are unclear, but expanded repeats cause triplet repeat expansion diseases (TREDs).
Purpose of the Study:
- To review structural features of triplet repeats in transcripts.
- To discuss pathogenic mechanisms of toxic RNA repeats in TREDs.
Main Methods:
- Literature review of existing knowledge on triplet repeats in transcripts.
- Analysis of pathogenic mechanisms linked to toxic RNA repeats.
Main Results:
- Expanded non-coding CUG/CGG repeats cause myotonic dystrophy type 1 and FXTAS.
- Expanded translated CAG repeats contribute to Huntington's disease and spinocerebellar ataxias.
- Pathogenic mechanisms include aberrant splicing, impaired nuclear transport, immune response induction, and disrupted miRNA/RNAi pathways.
Conclusions:
- Mutant RNA repeats trigger diverse pathogenic mechanisms in TREDs.
- Further research is needed to fully elucidate mechanisms of pathogenesis driven by mutant RNA repeats.
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