Identification of Plant Chromatin Interaction Networks Using IP-MS and co-IP

Methods Mol Biol. 2025:2873:129-143. doi: 10.1007/978-1-0716-4228-3_8.

Abstract

Proteins often act in concert to perform their function. Thus, the identification of protein complexes is crucial if we want to understand how they work. In this chapter, we present a highly sensitive protocol for the immunoprecipitation of nuclear chromatin-linked proteins in Arabidopsis thaliana that does not rely on time-consuming nuclei extraction. Interaction partners are identified using mass spectrometry and confirmed by co-immunoprecipitation. To help solubilize chromatin-bound proteins and eliminate nonspecific interactions of proteins binding the same DNA stretch, we include an enzymatic digestion step to remove DNA before immunoprecipitation. Our protocol offers a simplified process using optimized buffers, which facilitates quick and effective immunoprecipitation. The outcome is high-quality eluates that are ideal for identifying proteins through MS.

Keywords: ATRX; Arabidopsis; Chromatin; Histone H3.3; Immunoprecipitation; Mass spectrometry; Protein–protein interactions.

MeSH terms

  • Arabidopsis Proteins* / metabolism
  • Arabidopsis* / genetics
  • Arabidopsis* / metabolism
  • Chromatin* / genetics
  • Chromatin* / metabolism
  • Immunoprecipitation / methods
  • Mass Spectrometry / methods
  • Protein Binding
  • Protein Interaction Mapping / methods
  • Protein Interaction Maps
  • Proteomics / methods

Substances

  • Chromatin
  • Arabidopsis Proteins