Epigenetic Modification Mass Spectrometry (LC–MS/MS) Services
Quantify epigenetic and epitranscriptomic modifications across RNA, DNA, proteins, and histones using LC–MS/MS—built for condition-to-condition comparisons (treated vs. control, KO vs. WT, time series, cohorts) and for orthogonal validation alongside sequencing or antibody-based enrichment assays.
- Quantifiable outputs, not just "detected/not detected": per-sample abundance tables + QC summary + interpretation-ready plots
- Multi-omics coverage in one portfolio: RNA/DNA modified nucleosides + protein PTMs + histone PTMs
- Flexible analysis modes: targeted (hypothesis testing) or untargeted (discovery prioritization)
- Reviewer-friendly reporting: transparent processing notes and evidence files (where applicable)

Overview
This LC–MS/MS service is designed for epigenetics and epitranscriptomics teams that need quantitative, cross-sample comparable modification readouts—especially when the key question is "how much does a modification change across conditions?" or when you want orthogonal chemical validation for sequencing- or antibody-enrichment–based results. Deliverables typically include per-sample abundance matrices (by module), an optional group-level comparison summary, and QC/processing documentation suitable for reproducible reporting.
Please note that LC–MS/MS primarily provides global/panel-level quantification and does not assign modifications to specific transcripts or genomic loci; if positional mapping is required, we recommend pairing with site-resolved sequencing assays such as MeRIP-Seq or broader Epigenomics Sequencing Services.
This service uses liquid chromatography–tandem mass spectrometry (LC–MS/MS) to quantify:
(1) nucleic-acid modifications (RNA/DNA, typically measured as modified nucleosides after controlled processing),
(2) glycoRNA-associated glycan composition and enrichment-based signals (study-dependent), and
(3) protein and histone post-translational modifications (PTMs).
Service summary table (modules + measurable feature counts)
| Module | What it measures | Measurable scope (as specified) |
|---|---|---|
| RNA modification MS (mRNA) | Modified nucleosides in mRNA | 18 modification types |
| RNA modification MS (tRNA) | Modified nucleosides in tRNA | 37 modification types |
| RNA modification MS (total RNA) | Modified nucleosides in total RNA | 26 modification types |
| GlycoRNA glycomics MS | N-/O-glycan composition in small RNA fraction | 60+ N-glycans; ~10 core2-type O-glycans |
| GlycoRNA modification MS (enriched fraction) | Enrichment-based detection of glycoRNA-associated signals | Discovery-oriented; examples include acp3U/galQ/manQ (feasibility-dependent) |
| DNA modification MS | Global DNA modification quantification | 5mC + 5hmC (optional exploration of 5fC where feasible) |
| Protein PTM MS | PTM-focused proteomics | Glyco/phospho/methyl/acetyl/ubiquitin (study-dependent) |
| Histone PTM MS | Histone modification profiling | 150+ histone PTM peptides |
What this is best for
"How much does this modification change between groups?" (quantitative comparison)
"Is my sequencing/enrichment signal reflected in global abundance?" (orthogonal validation)
"Which conditions should I prioritize for deeper mapping?" (screening/prioritization)
Nucleic Acid Modification Mass Spectrometry
A) RNA Modification Mass Spectrometry (mRNA / tRNA / total RNA)
RNA chemical modifications regulate RNA stability, structure, splicing/translation, and RNA–protein interactions. This module provides quantitative profiling of multiple modified nucleosides to support robust condition-to-condition comparisons.
Service specifications
- Sample input: 0.5–1 µg RNA
- Analyzable samples: mRNA, tRNA, and total RNA
- MS acquisition: ~15 min per sample (method/instrument dependent)
- Analysis mode: targeted or untargeted
- Expected results: quantitative abundance readouts for the modification panels below (tables + QC + plots)
mRNA panel (18 detectable modifications)
| # | Modification | Abbrev. |
|---|---|---|
| 1 | Dihydrouridine | D |
| 2 | 5-hydroxymethylcytidine | hm5C |
| 3 | Pseudouridine | Ψ |
| 4 | 3-methylcytidine | m3C |
| 5 | 1-methyladenosine | m1A |
| 6 | 5-methylcytidine | m5C |
| 7 | 7-methylguanosine | m7G |
| 8 | 2′-O-methylcytidine | Cm |
| 9 | Inosine | I |
| # | Modification | Abbrev. |
|---|---|---|
| 10 | 5-methyluridine | m5U |
| 11 | 5-formylcytidine | f5C |
| 12 | 2′-O-methyluridine | Um |
| 13 | 1-methylguanosine | m1G |
| 14 | 2′-O-methylguanosine | Gm |
| 15 | N4-acetylcytidine | ac4C |
| 16 | 2′-O-methyladenosine | Am |
| 17 | N6-methyladenosine | m6A |
| 18 | N6,2′-O-dimethyladenosine | m6Am |
tRNA panel (37 detectable modifications)
| # | Modification | Abbrev. |
|---|---|---|
| 1 | Dihydrouridine | D |
| 2 | Pseudouridine | Ψ |
| 3 | 3-methylcytidine | m3C |
| 4 | 1-methyladenosine | m1A |
| 5 | 5-hydroxyuridine | ho5U |
| 6 | 5-methylcytidine | m5C |
| 7 | 1-methylpseudouridine | m1Ψ |
| 8 | 7-methylguanosine | m7G |
| 9 | 2′-O-methylcytidine | Cm |
| 10 | Inosine | I |
| 11 | 5-methyluridine | m5U |
| 12 | 5-formylcytidine | f5C |
| 13 | 2′-O-methyluridine | Um |
| 14 | 2-methyladenosine | m2A |
| 15 | 1-methylguanosine | m1G |
| 16 | 2′-O-methylguanosine | Gm |
| 17 | 1-methylinosine | m1I |
| 18 | N2-methylguanosine | m2G |
| 19 | N4-acetylcytidine | ac4C |
| # | Modification | Abbrev. |
|---|---|---|
| 20 | 2′-O-methyladenosine | Am |
| 21 | N6-methyladenosine | m6A |
| 22 | N2,N2-dimethylguanosine | m22G |
| 23 | N6-isopentenyladenosine | i6A |
| 24 | 5-carboxymethyluridine | cm5U |
| 25 | 2-thiocytidine | s2C |
| 26 | 5-methoxycarbonylmethyluridine | mcm5U |
| 27 | 5-carboxymethylaminomethyluridine | cmnm5U |
| 28 | 5-methoxyuridine | mo5U |
| 29 | 3-(3-amino-3-carboxypropyl)uridine | acp3U |
| 30 | uridine 5-oxyacetic acid | cmo5U |
| 31 | 5-methoxycarbonylmethyl-2-thiouridine | mcm5s2U |
| 32 | 5,2′-O-dimethyluridine | m5Um |
| 33 | 2-methylthio-N6-threonylcarbamoyladenosine | ms2t6A |
| 34 | 4-thiouridine | s4U |
| 35 | N6-threonylcarbamoyladenosine | t6A |
| 36 | 2-thiouridine | s2U |
| 37 | 5-methyl-2-thiouridine | m5s2U |
total RNA panel (26 detectable modifications)
| # | Modification | Abbrev. |
|---|---|---|
| 1 | Dihydrouridine | D |
| 2 | Pseudouridine | Ψ |
| 3 | 3-methylcytidine | m3C |
| 4 | 1-methyladenosine | m1A |
| 5 | 5-methylcytidine | m5C |
| 6 | 1-methylpseudouridine | m1Ψ |
| 7 | 7-methylguanosine | m7G |
| 8 | 2′-O-methylcytidine | Cm |
| 9 | Inosine | I |
| 10 | 5-methyluridine | m5U |
| 11 | 2′-O-methyluridine | Um |
| 12 | 1-methylguanosine | m1G |
| 13 | 2′-O-methylguanosine | Gm |
| # | Modification | Abbrev. |
|---|---|---|
| 14 | 1-methylinosine | m1I |
| 15 | N2-methylguanosine | m2G |
| 16 | N4-acetylcytidine | ac4C |
| 17 | 2′-O-methyladenosine | Am |
| 18 | N6-methyladenosine | m6A |
| 19 | N2,N2-dimethylguanosine | m22G |
| 20 | N6-isopentenyladenosine | i6A |
| 21 | 5-carboxymethyluridine | cm5U |
| 22 | 5-methoxycarbonylmethyluridine | mcm5U |
| 23 | 5-carboxymethylaminomethyluridine | cmnm5U |
| 24 | 5-methoxycarbonylmethyl-2-thiouridine | mcm5s2U |
| 25 | N6-threonylcarbamoyladenosine | t6A |
| 26 | 3-methyluridine | m3U |
How to choose the RNA module (quick, practical)
- Choose mRNA: when your question is transcript regulation and you want mRNA-centric modified nucleoside quantification.
- Choose tRNA: when you expect stress/translation remodeling or want a rich modification spectrum.
- Choose total RNA: when you want a broad view (often dominated by abundant RNA species) for global shifts and screening.
B) GlycoRNA Glycomics Mass Spectrometry
GlycoRNA has been reported as RNA species linked to glycans and displayed at the cell surface, motivating glycan-composition profiling for hypothesis generation and comparative studies.
Service specifications
- Sample input: 2–10 µg small RNA (consult for sample-type specifics)
- Analyzable samples: small RNA fraction
- Processing options: N-glycan profiling and/or O-glycan profiling (module selection by study goal)
- MS options: LC-based analysis; MALDI can be considered for large cohorts depending on design
- Expected results: composition-level quantification of 60+ N-glycans and ~10 core2-type O-glycans (reported as quantitative features suitable for group comparison)
C) GlycoRNA Modification Mass Spectrometry (Enriched Fraction)
Because glycoRNA abundance is expected to be very low, this module is designed around enrichment + LC–MS/MS detection for discovery-oriented profiling.
Service specifications
- Sample input: 30–120 µg total RNA (consult recommended range by sample type)
- Analyzable samples: enriched glycoRNA fraction
- MS acquisition: ~20 min per sample (method/instrument dependent)
- Analysis mode: untargeted/discovery-oriented
- Expected results: detection of glycoRNA-linked modification signals and co-existing features (examples include acp3U/galQ/manQ, feasibility-dependent and guided by controls)
For transcript- or site-resolved mapping to complement enrichment-based LC–MS/MS signals, see our GlycoRNA-Seq service.
D) DNA Modification Mass Spectrometry
This module provides a quantitative global readout of DNA methylation and hydroxymethylation markers to support epigenetic comparisons and orthogonal validation.
Service specifications
- Sample input: 0.5–1 µg
- Analyzable samples: DNA
- MS acquisition: ~15 min per sample (method/instrument dependent)
- Analysis method: global DNA modification quantification (configured to project goals)
- Expected results: standard detection of 5mC and 5hmC; optional exploration of 5fC where feasible (standards/controls may be recommended)
Protein Modification Mass Spectrometry (PTM Proteomics)
Protein PTMs connect signaling, metabolism, and transcriptional control. This module supports PTM-oriented proteomics to capture PTM shifts that may regulate epigenetic writers/erasers/readers, transcription factors, and chromatin-associated complexes.
- Analyzable samples (examples): cells, tissues, purified protein; biofluids such as serum/urine/CSF by consultation
- Sample input (typical references): cells ≥ 1×10^7 per sample; protein ≥ 1 mg per sample (study dependent)
- Analysis mode: PTM-focused workflows aligned to project goals (e.g., glycoproteomics, phosphoproteomics)
- Expected results: quantitative outputs at peptide/site/protein level (method dependent), with PTM-category summaries and prioritized change lists
- Glycosylation
- Phosphorylation
- Methylation
- Acetylation
- Ubiquitination
- PTM-centric quant tables (per sample) + group comparison summaries (if design supports)
- Identification/confidence notes and QC summary
- Top-changes list to guide mechanism experiments and targeted follow-up
Histone Modification Mass Spectrometry
Histone PTMs are core epigenetic regulators. Histone MS provides a multi-mark, parallel view of chromatin state shifts and can complement ChIP-based assays by offering broad mark coverage in one measurement.
Service specifications
- Sample input: 1–10 µg histone extract
- Analyzable samples: histone extracts from cells or tissues
- Sample processing: histone extraction + MS pre-processing (workflow depends on sample type)
- MS acquisition: ~20 min per sample (method/instrument dependent)
- Analysis method: quantitative histone PTM profiling
- Expected results: detection and quantification of 150+ histone PTM peptides (module definition), supporting cross-mark interpretation and follow-up mark selection
Representative histone marks frequently reported (illustrative subset)
H3K4me1/2/3, H3K9me1/2/3, H3K9ac, H3S10ph, H3K14ac, H3K18ac, H3K27me1/2/3, H3K27ac, H3K36me1/2/3, H3K56me1/2/3, H3K56ac, H3K79me1/2/3, H4K5ac, H4K8ac, H4K12ac, H4K16ac, H4K20me1/2/3, etc.
Applications
This service is typically selected when you need quantitative, decision-ready outputs:
- Mechanism studies: evaluate how perturbing writers/erasers/readers changes RNA/DNA marks and histone/protein PTMs.
- Orthogonal validation: confirm whether sequencing/enrichment signals reflect real abundance shifts at the nucleoside/PTM level.
- Screening & prioritization: rank treatments/conditions before deeper locus mapping (e.g., which condition shows the strongest global shift).
- Multi-layer regulation: align RNA modification trends with histone marks and protein PTM pathways for coherent interpretation.
- GlycoRNA exploration: compare glycan composition and enrichment-based signals across conditions.
Quick selection guide
| Your question | Suggested module |
|---|---|
| "Is global m6A/m5C/m7G changing across conditions?" | RNA modification MS (mRNA) |
| "Do tRNA modifications remodel under stress?" | RNA modification MS (tRNA) |
| "I want a broad screening readout of RNA modifications." | RNA modification MS (total RNA) |
| "Is DNA methylation/hydroxymethylation shifting globally?" | DNA modification MS |
| "Which histone marks shift in parallel?" | Histone PTM MS |
| "Are PTM pathways changing with epigenetic perturbation?" | Protein PTM MS |
| "I want glycoRNA-related glycan composition profiles." | GlycoRNA glycomics MS |
| "I want enrichment-based glycoRNA signal exploration." | GlycoRNA modification MS |
Service Workflow
- Project definition (study goal → module choice)
We align the module(s) to your biology question, sample types, and comparison design (groups, replicates, and expected effect sizes). This step determines whether targeted confirmation or untargeted discovery is the best fit. - Sample intake and QC/feasibility review
We review sample matrix, extraction background, and feasibility for each module. Where needed, we recommend cleanup/enrichment to reduce confounders (e.g., salts, detergents, carryover). - Module-specific sample processing
- RNA/DNA modules: processed into measurable analytes for LC–MS/MS quantification.
- Protein/histone modules: extraction/digestion workflows and PTM-appropriate preparation (project-defined).
- GlycoRNA modules: small RNA fraction processing or enrichment-based preparation (study-defined).
- LC–MS/MS acquisition and run-level QC
Run design includes appropriate QC checks and method settings aligned to the selected module. Acquisition parameters are selected to support quantitative comparability across groups. - Data processing, normalization, and QC reporting
Peak integration, QC checks, and normalization strategy (when applicable). Replicate consistency and outlier flags are documented so your team can trust the comparisons. - Reporting and handoff
You receive a report package with tables, QC summaries, and plots that can be directly used for internal decisions, presentations, and manuscript figures (RUO).
Bioinformatics & Data Analysis
Your outputs are designed to be "action-ready": easy to compare groups, defend in peer review, and select follow-up experiments.
| Analysis component | What you receive | Why it matters |
|---|---|---|
| Quantification matrices | per-sample abundance tables (CSV/XLSX) + group summaries | immediate comparisons, plotting, and downstream stats |
| QC summary | run-level QC notes, flagged items, consistency checks | confidence in comparability across groups |
| Evidence files (as applicable) | representative chromatograms / peak integration snapshots | supports interpretability and reporting |
| Visualization | box/bar plots, heatmaps, PCA/cluster (when appropriate) | fast decision-making and presentation-ready outputs |
| Comparative outputs (optional) | fold-change summaries, effect size tables | helps prioritize conditions/targets |
| Interpretation notes | short, study-aligned summary of key findings | turns numbers into next-step actions |
Deliverables
You receive a deliverable set intended for fast decisions and easy collaboration:
- Results tables
- per-sample quantification matrix
- group summary table (if grouping provided)
- optional comparison table (fold change / effect size, if requested)
- QC package
- run-level QC summary and any exceptions
- replicate consistency notes (where applicable)
- evidence snapshots (representative, as applicable)
- Figure set
- plots suitable for internal review and manuscript drafting (RUO)
- optional PCA/heatmap if sample design supports
- Methods snapshot
- concise process summary suitable for a Methods section (RUO)
- module-specific notes that support reproducibility
Sample Requirements
Accepted sample types
- RNA: mRNA, tRNA, total RNA; small RNA fraction (for glycoRNA glycomics)
- DNA: genomic DNA
- Protein: cells/tissues/purified protein; selected biofluids by consultation
- Histones: histone extracts from cells or tissues
Sample requirement table
| Module | Sample type | Input amount (as specified) |
|---|---|---|
| RNA modification MS (mRNA/tRNA/total RNA) | RNA | 0.5–1 µg |
| GlycoRNA glycomics MS | small RNA fraction | 2–10 µg |
| GlycoRNA modification MS (enriched fraction) | total RNA | 30–120 µg |
| DNA modification MS | DNA | 0.5–1 µg |
| Protein PTM MS | cells or protein (examples) | cells ≥ 1×10^7; protein ≥ 1 mg |
| Histone PTM MS | histone extract | 1–10 µg |
FAQ
References
- Xie Y, Brás-Costa C, Lin Z, Garcia BA. Mass Spectrometry Analysis of Nucleic Acid Modifications: From Beginning to Future. Mass Spectrometry Reviews. 2024.
- Xie Y, Chai P, Till NA, et al. The modified RNA base acp3U is an attachment site for N-glycans in glycoRNA. Cell. 2024.
- Kellner S. et al. Absolute and relative quantification of RNA modifications via biosynthetic isotopomers. Nucleic Acids Research (2014).
- Mathur L. et al. Quantitative analysis of m6A RNA modification by LC–MS. STAR Protocols (2021).
- Flynn RA, Pedram K, Malaker SA, et al. Small RNAs are modified with N-glycans and displayed on the surface of living cells. Cell. 2021.