Which m6A Antibody Should I Use for MeRIP-seq?

Choose an antibody that is monoclonal where possible, lot-tested, and validated for RNA immunoprecipitation rather than only for dot blot. Then validate it in your own hands with three checks:

1. Dot blot with defined inputs — synthetic m6A-containing versus unmethylated RNA, at matched concentrations.
2. Competition — signal reduced by free m6A nucleotide, not by unmodified nucleotide.
3. Biological control — reduced signal after METTL3 knockdown, and increased signal after FTO/ALKBH5 depletion, using the same antibody.

Most published MeRIP-seq datasets report none of these, which is why cross-study comparisons are unreliable.

• • Affinity and avidity determine which sites are enriched: an antibody with lower affinity under-represents low-stoichiometry sites, which are the majority.
• • Cross-reactivity with unmodified RNA or with other modifications inflates background and creates peaks at GC-rich regions.
• • Lot-to-lot variation is substantial for polyclonal reagents; a changed lot can shift peak sets between experiments.
• • Fixation and crosslinking are not part of standard MeRIP, so the readout depends heavily on fragmentation and immunoprecipitation conditions.

Practical consequence: an antibody that performs in dot blot may still perform poorly in MeRIP. Ask for MeRIP-validated data, not dot-blot data alone.

The fourth row is the one that makes datasets comparable: a spike-in turns IP efficiency from an uncontrolled variable into a measured one.

• • Peaks are not sites. Standard MeRIP gives ~100-nt resolution; a peak may contain several candidate adenosines.
• • Enrichment is not stoichiometry. Most methods cannot report the fraction of transcripts methylated at a site.
• • Input normalization matters, and so does library size; comparing peaks across studies without matched processing is unreliable.
• • Antibody-dependent regions exist. Some peaks replicate only with certain antibodies, which is a strong hint of cross-reactivity.

If your question is site-level, an antibody-based map may not be the right primary dataset:

• • miCLIP or m6A-CLIP for near-single-base resolution.
• • SELECT or site-specific assays for quantitative measurement at a locus.
• • Direct RNA sequencing for native detection without antibodies.

MeRIP is the right tool for discovery at transcriptome scale, and the wrong tool for adjudicating a single adenosine.

EDITGENE runs m6A mapping with lot-documented antibodies, spike-in normalization, dot blot and competition validation, and METTL3-knockdown controls — and pairs the map with site-level assays when the claim concerns a specific adenosine.

Tell us the transcript and the site. Contact EDITGENE to request a project consultation or quote.

Antibody performance varies by lot, protocol, and input; no single reagent is universally superior, and validation in the user's own system is required.

MeRIP-seq peaks are candidates at limited resolution and do not report methylation stoichiometry; site-level claims require an orthogonal, preferably quantitative, assay.

• • Dominissini D, et al. Topology of the human and mouse m6A RNA methylomes. Nature. 2012;485:201–206.
• • Meyer KD, et al. Comprehensive analysis of mRNA methylation reveals enrichment in 3′ UTRs and near stop codons. Cell. 2012;149:1635–1646.
• • Linder B, et al. Single-nucleotide-resolution mapping of m6A and m6Am throughout the transcriptome. Nature Methods. 2015;12:767–772.
• • Zaccara S, et al. Reading, writing and erasing mRNA methylation. Nature Reviews Molecular Cell Biology. 2019;20:608–624.