p23 and HSP20/alpha-crystallin proteins define a conserved sequence domain present in other eukaryotic protein families

FEBS Lett. 2002 Oct 9;529(2-3):162-7. doi: 10.1016/s0014-5793(02)03321-5.


We identified families of proteins characterized by the presence of a domain similar to human p23 protein, which include proteins such as Sgt1, involved in the yeast kinetochore assembly; melusin, involved in specific interactions with the cytoplasmic integrin beta1 domain; Rar1, related to pathogenic resistance in plants, and to development in animals; B5+B5R flavo-hemo cytochrome NAD(P)H oxidoreductase type B in humans and mice; and NudC, involved in nucleus migration during mitosis. We also found that p23 and the HSP20/alpha-crystallin family of heat shock proteins, which share the same three-dimensional folding, show a pattern of conserved residues that points to a common origin in the evolution of both protein domains. The p23 and HSP20/alpha-crystallin phylogenetic relationship and their similar role in chaperone activity suggest a common function, probably involving protein-protein interaction, for those proteins containing p23-like domains.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Drosophila melanogaster / chemistry
  • Drosophila melanogaster / metabolism*
  • HSP20 Heat-Shock Proteins
  • Heat-Shock Proteins / chemistry
  • Heat-Shock Proteins / metabolism*
  • Models, Molecular
  • Molecular Chaperones / chemistry
  • Molecular Chaperones / metabolism*
  • Molecular Sequence Data
  • Phosphoproteins / chemistry
  • Phosphoproteins / metabolism*
  • Prostaglandin-E Synthases
  • Protein Conformation
  • Sequence Homology, Amino Acid
  • alpha-Crystallins / chemistry
  • alpha-Crystallins / metabolism*


  • HSP20 Heat-Shock Proteins
  • Heat-Shock Proteins
  • Molecular Chaperones
  • Phosphoproteins
  • alpha-Crystallins
  • PTGES3 protein, human
  • Prostaglandin-E Synthases