A new approach combining LC-MS and multivariate statistical analysis for revealing changes in histone modification...

Area of Science:

• Epigenetics
• Molecular Biology
• Biochemistry

Background:

• Histone post-translational modifications (PTMs) regulate gene expression by altering chromatin structure.
• The 'histone code' reflects dynamic transcriptional states influenced by environmental factors.
• Detecting epigenetic disruption is crucial for understanding cellular responses to xenobiotics.

Purpose of the Study:

• To introduce a global screening approach for identifying histone-level epigenetic disruptions.
• To enable rapid and reliable comparison of histone PTMs and variants in human cells.
• To demonstrate the utility of this method in detecting changes induced by histone deacetylase inhibitors.

Main Methods:

• Utilized ultra-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS).
• Analyzed histone acid-extracts from BeWo human choriocarcinoma cells treated with sodium butyrate (SB).
• Applied multivariate statistics to mass spectral profiles for sample discrimination.

Main Results:

• Successfully discriminated between control and SB-treated samples based on mass spectral profiles.
• Identified specific acetylated and methylated forms of core histones as biomarkers for SB treatment.
• Demonstrated the feasibility of a single LC-MS experiment for relative abundance comparison of histone PTMs.

Conclusions:

• The developed histonomic screening approach is effective for detecting epigenetic disruption.
• This untargeted method can serve as a valuable exploratory tool for xenobiotic exposure studies.
• The findings highlight the sensitivity of histone modifications to HDAC inhibition.