A protein import receptor in pea chloroplasts, Toc86, is only a proteolytic fragment of a larger polypeptide

FEBS Lett. 1998 Dec 11;441(1):59-62. doi: 10.1016/s0014-5793(98)01525-7.


The protein import complex of the chloroplastic outer envelope (Toc-complex) contains a prominent subunit of 86 kDa molecular weight (Toc86). Toc86 was identified as a putative precursor receptor. The Arabidopsis genome sequencing project indicates that Toc86 represents only a proteolytic fragment of a larger polypeptide of 160 kDa. The 160-kDa protein, which we name Toc160, is only present in significant amounts in pea chloroplasts isolated under stringent conditions. The capacity of chloroplasts to import an in vitro translated precursor protein correlates well with the integrity of Toc160. We conclude that Toc160 is still a bonafide subunit of the protein import machinery of chloroplasts.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics
  • Chloroplasts / chemistry*
  • Genome, Plant
  • Intracellular Membranes / chemistry*
  • Membrane Proteins / chemistry*
  • Membrane Proteins / isolation & purification
  • Molecular Sequence Data
  • Peas / chemistry*
  • Peptide Fragments / chemistry*
  • Peptide Fragments / isolation & purification
  • Plant Proteins / chemistry*
  • Plant Proteins / isolation & purification
  • Sequence Alignment
  • Sequence Homology, Amino Acid


  • Membrane Proteins
  • Peptide Fragments
  • Plant Proteins

Associated data

  • GENBANK/AC002330
  • GENBANK/AF069298