Epigenetics

Epigenetics encompasses heritable alterations in gene expression that occur without changes to the DNA sequence itself. These modifications influence chromatin structure and the accessibility of genomic regions, thereby controlling cellular identity and function. Major epigenetic mechanisms include DNA methylation at cytosine bases, post-translational modifications of histone proteins and regulatory non-coding RNAs. Together these dynamic but reversible marks orchestrate processes such as embryonic development, X-chromosome inactivation, genomic imprinting and responses to environmental stimuli. Dysregulation of the epigenome underpins many disease states, while its plasticity offers opportunities for novel diagnostic markers and targeted therapies.

Research from Nature Portfolio

Studies of innate immunity have shown that the transcription co-activator MKL1 partners with NF-κB to establish an active chromatin landscape. MKL1 recruits the H3K4 methyltransferase SET1 to pro-inflammatory gene promoters, generating trimethylation at histone H3 lysine 4 and licensing robust cytokine expression. This work defines a direct link between histone methylation and inflammatory signalling.

In plant development, telomeric repeat binding proteins (TRBs) have been shown to coordinate opposing histone marks at master regulators. TRBs bind telobox motifs and bring in both the H3K4 demethylase JMJ14 and Polycomb-repressive complex 2, thereby removing active marks and depositing H3K27me3. This dual mechanism enforces stable silencing of key developmental genes.

Research from all publishers

An integrative analysis combining neuroimaging, brain-wide transcriptomics and peripheral DNA methylation arrays has mapped associations between grey-matter volume reductions in major depressive disorder and differentially methylated CpG sites. The study identified epigenetic variation in genes linked to synaptic transmission within the anterior cingulate and frontal cortices and demonstrated inverse relationships between peripheral methylation and regional gene expression, forging a bridge between blood-based markers and brain structure.

Research in adolescent depression has shown that methylation of the exon IV promoter region of the brain-derived neurotrophic factor gene is significantly decreased relative to healthy controls and correlates inversely with symptom severity. These promoter-specific changes normalise following antidepressant treatment, pointing to dynamic BDNF methylation as a state-dependent biomarker for therapeutic monitoring in young patients.

Epigenetics publication trend

The graph below shows the total number of articles in epigenetics across all publications each year (not limited to Nature Index journals).

Technical terms

Epigenetics: heritable and reversible modifications to chromatin that regulate gene expression without altering the DNA sequence.

DNA methylation: covalent addition of a methyl group to cytosine bases in CpG dinucleotides, often linked to transcriptional repression.

Histone modification: post-translational changes to histone proteins (e.g. methylation, acetylation) that influence nucleosome stability and gene accessibility.

H3K4me3: trimethylation of histone H3 at lysine 4, a mark associated with active promoters.

H3K27me3: trimethylation of histone H3 at lysine 27, a repressive mark deposited by Polycomb Repressive Complex 2.

Transcription factor: protein that binds specific DNA sequences to regulate gene transcription.

Chromatin accessibility: the degree to which DNA is exposed to transcriptional machinery, governed by nucleosome positioning and histone marks.

References

1. MKL1 defines the H3K4Me3 landscape for NF-κB dependent inflammatory response. Scientific Reports (2017).
2. Arabidopsis TRB proteins function in H3K4me3 demethylation by recruiting JMJ14. Nature Communications (2023).
3. Telobox motifs recruit CLF/SWN–PRC2 for H3K27me3 deposition via TRB factors in Arabidopsis. Nature Genetics (2018).
4. Integrative omics analysis reveals epigenomic and transcriptomic signatures underlying brain structural deficits in major depressive disorder. Translational Psychiatry (2024).
5. Biomarkers of Depression among Adolescent Girls: BDNF and Epigenetics. International Journal of Molecular Sciences (2024).