dCypher™ Nucleosome Full Panel

Access to epigenetic diversity in the context of a physiological nucleosome enables broad end-user applications, including nucleosome binding studies (e.g. chromatin reader binding preferences [2-4] see Figure 2), enzyme screening assays (e.g. identification of preferred substrates), and antibody specificity testing (e.g. for applications where histone peptide specificity is an insufficient surrogate). The biotin group on the DNA facilitates a wide variety of applications involving streptavidin capture.

Q: How many assay points of each nucleosome are supplied?
A: This varies according to the sensitivity of the end application. For some context, the supplied format is sufficient to perform >35 AlphaScreen assays, >30 IP-qPCR experiments, and 3-5 immunoblotting experiments.

Q: How do I store the plate? Can I dilute the nucleosomes?
A: The nucleosomes are stable for 6 months at -80ºC in the supplied format (1.5 µM). Freeze/thaw cycles should be limited (2-3 times). When diluted below 1.5 µM, a carrier protein (e.g. BSA) must be used to supplement the concentration, otherwise, stability is affected. For example, in our SNAP-ChIP product line, nucleosomes are diluted to 0.6 nM in 10 mM sodium cacodylate pH 7.5, 100 mM NaCl, 1 mM EDTA, 50% glycerol (w/v), 1x Protease Inhibitor cocktail, 100 μg/mL BSA, 10 mM β-mercaptoethanol. In this formulation, the nucleosomes are stable at -20ºC (where they do not freeze) for 6 months.

For applications that may not be compatible with the SNAP-ChIP buffer, such as AlphaScreen, EpiCypher routinely dilutes nucleosomes to 80 nM in assay buffer (20 mM Tris pH 7.5, 0.01% BSA, 0.01% NP-40, 2mM DTT). Under these conditions the nucleosomes are stable for ~2 weeks at -80°C.

*Note: extremely high amounts of salt (>650 mM) and ionic detergents (e.g. SDS) will disrupt nucleosome stability.