Recombinant histone octamers are defined nucleosome core particles assembled in vitro from purified recombinant histone proteins (H2A, H2B, H3, and H4). These octamers serve as standardized building blocks for chromatin reconstitution on defined DNA sequences, enabling biochemical, biophysical, and structural studies of nucleosome dynamics, histone-DNA interactions, chromatin remodeling complexes, and histone-modification enzymes.
Key Advantages
- Defined Composition: Produced from fully recombinant histones with known sequences and modification states (unmodified or site-specifically modified), eliminating variability associated with native chromatin preparations.
- High Purity and Consistency: Controlled expression and purification processes ensure reproducible biochemical performance and lot-to-lot consistency.
- Ready-to-Assemble Format: Available as pre-assembled octamers or as purified histone monomers for custom assembly, reducing preparation time and experimental variability.
- Customizability: Offered with histone variants such as H3.3, H2A.Z, and macroH2A, as well as specific point mutations or post-translational modification mimics including methyl-lysine and acetyllysine analogs.
- Broad Compatibility: Suitable for salt-gradient and salt-dialysis nucleosome assembly, nucleosome positioning studies, cryo-EM, SAXS, EMSA, chromatin remodeling assays, and single-molecule analyses.
Applications
- In Vitro Nucleosome Reconstitution: Generation of defined chromatin templates for studying chromatin remodelers, transcription factors, and histone-modifying enzymes.
- Structural Biology: Investigation of nucleosome architecture and chromatin complexes using cryo-electron microscopy (cryo-EM), X-ray crystallography, and small-angle X-ray scattering (SAXS).
- Biophysical Studies: Analysis of nucleosome stability, DNA accessibility, and chromatin dynamics through single-molecule FRET, optical tweezers, and related techniques.
- Assay Standards and Controls: Use as defined chromatin substrates for enzymatic assays, antibody validation, and calibration of MNase-, ATAC-, and CUT&Tag-based workflows.