Prosystemin from potato, black nightshade, and bell pepper: primary structure and biological activity of predicted systemin polypeptides

Plant Mol Biol. 1998 Jan;36(1):55-62. doi: 10.1023/a:1005986004615.


Prosystemin is the precursor protein of the 18 amino acid wound signal systemin which activates systemic defense in tomato leaves against insect herbivores (McGurl B, Pearce G, Orozco-Cardenas M, Ryan CA, Science 255 (1992) 1570-1573). Here, we report the isolation of cDNA sequences encoding prosystemin from potato (Solanum tuberosum), black nightshade (S. nigrum), and bell pepper (Capsicum annuum), all members of the Solanaceae family, using reverse-transcription polymerase chain reaction (RT-PCR). Pairwise comparisons of the predicted prosystemin proteins from the three species with tomato prosystemin and among each other indicated sequence identities ranging from 73% to 88%. The deduced systemin polypeptides were synthesized and tested for their capacities to induce the synthesis of the defensive proteinase inhibitors in tomato leaves. Potato and pepper systemins were approximately as active as tomato systemin, whereas nightshade systemin was ten-fold less active. The accumulation of proteinase inhibitor mRNA transcripts could be induced in each of these plants by treatment with the homologous systemin. As in the tomato, in potato, black nightshade, and bell pepper plants, prosystemin homologs appear to function as precursors of systemic wound signals.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Atropa belladonna / chemistry
  • Atropa belladonna / metabolism*
  • DNA, Complementary
  • Lycopersicon esculentum / chemistry
  • Lycopersicon esculentum / metabolism
  • Molecular Sequence Data
  • Peptides / metabolism
  • Plant Proteins / biosynthesis*
  • Plant Proteins / chemistry*
  • Plant Proteins / isolation & purification
  • Plants, Medicinal*
  • Plants, Toxic*
  • Polymerase Chain Reaction
  • Protease Inhibitors / metabolism
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / isolation & purification
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Solanum tuberosum / chemistry
  • Solanum tuberosum / metabolism*
  • Transcription, Genetic
  • Vegetables / chemistry
  • Vegetables / metabolism*


  • DNA, Complementary
  • Peptides
  • Plant Proteins
  • Protease Inhibitors
  • Recombinant Proteins
  • prosystemin protein, Lycopersicon esculentum
  • systemin

Associated data

  • GENBANK/AF000373
  • GENBANK/AF000374
  • GENBANK/AF000375
  • GENBANK/AF000376