A repeating 11-mer amino acid motif and plant desiccation

Plant J. 1993 Mar;3(3):363-9. doi: 10.1046/j.1365-313x.1993.t01-19-00999.x.

Abstract

Among the proteins that accumulate as plant seeds desiccate are several protein families that are composed principally of a tandemly repeated 11-mer amino acid motif. Proteins containing the same motif accumulate in the desiccating leaves of a desiccation-tolerant plant species. This motif is characterized by apolar residues in positions 1, 2, 5 and 9, and charged or amide residues in positions 3, 6, 7, 8 and 11. An alpha helical arrangement of the 11-mer repeating unit gives an amphiphilic helix whose hydrophobic stripe twists in a right-handed fashion around the helix. Should these proteins dimerize via binding of their hydrophobic faces, a right-handed coiled coil would be formed. Such a structure has not previously been observed. A conceivable function for these proteins in ion sequestration in the desiccated state is proposed.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Adaptation, Physiological
  • Amino Acid Sequence
  • Heat-Shock Proteins / genetics*
  • Molecular Sequence Data
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plants / genetics*
  • Plants / metabolism
  • Repetitive Sequences, Nucleic Acid*
  • Sequence Homology, Amino Acid
  • Water / metabolism*

Substances

  • Heat-Shock Proteins
  • Plant Proteins
  • late embryogenesis abundant protein, plant
  • Water