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Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
Published on: November 22, 2014
Biotin is not a natural histone modification.
Shannon Healy1, Beatriz Perez-Cadahia, Dongxin Jia
1Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta, Canada T2N 4N1. shannon.healy@tut.fi
Biochimica Et Biophysica Acta
|September 23, 2009
Summary
This study investigated histone biotinylation, a proposed mechanism for gene regulation. Researchers found no evidence of biotin attachment to native histones in cell cultures, suggesting alternative gene expression pathways.
Area of Science:
- Biochemistry
- Molecular Biology
- Epigenetics
Background:
- Biotin, a vitamin, acts as a cofactor for carboxylases.
- Biotin is implicated in gene regulation, including transcription and silencing.
- Histone biotinylation has been proposed as a mechanism for biotin's regulatory role.
Purpose of the Study:
- To critically evaluate methods for detecting histone biotinylation.
- To determine if histone biotinylation occurs in vivo.
- To establish the presence or absence of biotin as a native histone modification.
Main Methods:
- Utilized [(3)H]-biotin uptake assays.
- Performed Western blot analysis on histones.
- Employed mass spectrometry on affinity-purified histone fragments.
Main Results:
- Biotin was readily detected on native carboxylases and in vitro biotinylated histones.
- No detectable biotin attachment was found on native histones from various cell cultures.
- Histone biotinylation was absent in native histones to a sensitivity of at least 1:100,000.
Conclusions:
- The proposed mechanism of histone biotinylation in gene regulation is not supported by current evidence.
- Biotin's regulatory impact on gene expression likely occurs through alternative pathways.
- Native histones do not appear to be biotinylated in vivo.
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