Related Experiment Video
Updated: Feb 22, 2026
Native Cell Membrane Nanoparticles System for Membrane Protein-Protein Interaction Analysis
Published on: July 16, 2020
Expression and purification of the full murine NPM2 and study of its interaction with protamines and histones
Katherine Ellard1, Jason J Serpa1,2, Evgeniy V Petrotchenko1,2
1Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8W 3P6.
Abstract:
Mouse nucleoplasmin M.NPM2 was recombinantly expressed and the protein consisting of the complete sequence was purified and characterized. Similar to its Xenopus laevis X.NPM2 counterpart, the protein forms stable pentameric complexes and exhibits an almost undistinguishable hydrodynamic ionic strength-dependent unfolding behavior. The interaction of N.PM2 with histones and mouse P1/P2 protamines revealed that these chromosomal proteins bind preferentially to the distal part of the nucleoplasmin pentamer. Moreover, the present work highlights the critical role played by histones H2B and H4 in the association of the histone H2A-H2B dimers and histone octamer with nucleoplasmin.
Insights
Mouse nucleoplasmin NPM2 protein was purified and characterized. It binds to histones and protamines, with histones H2B and H4 being crucial for this interaction.
Area of Science:
- Molecular Biology
- Biochemistry
- Chromatin Biology
Background:
- Nucleoplasmins are crucial for nucleosome assembly and chromatin organization.
- Mouse nucleoplasmin NPM2 (M.NPM2) function and interaction with core histones and protamines are not fully understood.
Purpose of the Study:
- To recombinantly express, purify, and characterize mouse nucleoplasmin NPM2.
- To investigate the interaction of M.NPM2 with histones and protamines.
- To elucidate the role of specific histones in M.NPM2 complex formation.
Main Methods:
- Recombinant protein expression and purification.
- Hydrodynamic and ionic strength-dependent unfolding studies.
- Chromosomal protein binding assays.
Main Results:
- M.NPM2 forms stable pentameric complexes, similar to its Xenopus counterpart.
- M.NPM2 exhibits comparable ionic strength-dependent unfolding behavior to X.NPM2.
- Histones and protamines bind to the distal part of the M.NPM2 pentamer.
- Histones H2B and H4 are critical for the association of histone dimers and octamers with M.NPM2.
Conclusions:
- Mouse nucleoplasmin NPM2 shares functional and structural similarities with its Xenopus homolog.
- M.NPM2 plays a role in chromatin organization through interactions with histones and protamines.
- Specific histone residues are essential for M.NPM2 complex assembly.
