New insights into the nucleophosmin/nucleoplasmin family of nuclear chaperones

Bioessays. 2007 Jan;29(1):49-59. doi: 10.1002/bies.20512.


Basic proteins and nucleic acids are assembled into complexes in a reaction that must be facilitated by nuclear chaperones in order to prevent protein aggregation and formation of non-specific nucleoprotein complexes. The nucleophosmin/nucleoplasmin (NPM) family of chaperones [NPM1 (nucleophosmin), NPM2 (nucleoplasmin) and NPM3] have diverse functions in the cell and are ubiquitously represented throughout the animal kingdom. The importance of this family in cellular processes such as chromatin remodeling, genome stability, ribosome biogenesis, DNA duplication and transcriptional regulation has led to the rapid growth of information available on their structure and function. The present review covers different aspects related to the structure, evolution and function of the NPM family. Emphasis is placed on the long-term evolutionary mechanisms leading to the functional diversification of the family members, their role as chaperones (particularly as it pertains to their ability to aid in the reprogramming of chromatin), and the importance of NPM2 as an essential component of the amphibian chromatin remodeling machinery during fertilization and early embryonic development.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Chromatin Assembly and Disassembly
  • Evolution, Molecular
  • Female
  • Humans
  • Male
  • Molecular Chaperones / chemistry
  • Molecular Chaperones / genetics
  • Molecular Chaperones / physiology
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / physiology*
  • Nucleoplasmins
  • Phosphoproteins / chemistry
  • Phosphoproteins / genetics
  • Phosphoproteins / physiology*
  • Phylogeny


  • Molecular Chaperones
  • NPM2 protein, human
  • NPM3 protein, human
  • Nuclear Proteins
  • Nucleoplasmins
  • Phosphoproteins
  • nucleophosmin