Frameshifting is required for production of the transposase encoded by insertion sequence 1

Proc Natl Acad Sci U S A. 1989 Jun;86(12):4609-13. doi: 10.1073/pnas.86.12.4609.


Insertion sequence IS1 has two coding frames, insA and insB, which are essential for its transposition. Here, we show that a frameshifting event in the -1 direction from the 3' end region of the insA frame to an open reading frame (B' frame), extending from the 5' end of the insB frame, is involved in production of the InsA-B'-InsB fusion protein that has IS1 transposase activity. The frameshifting event is likely to have occurred at the sequence AAAAAC where the insA frame overlaps the B' frame. Interestingly, this sequence is also present in one of the two sequences identified in retroviruses as frameshift signals for production of transframe polyproteins from the overlapping genes gag-pro or gag-pro-pol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA Transposable Elements*
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Genes*
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Mutation
  • Nucleotidyltransferases / genetics*
  • Restriction Mapping
  • Shigella sonnei / enzymology
  • Shigella sonnei / genetics*
  • Transposases


  • DNA Transposable Elements
  • Nucleotidyltransferases
  • Transposases

Associated data

  • GENBANK/M27083