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Fret-Stop-Fret TOPO
(Plasmid #22774)

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Available to Academic and Nonprofits Only


  • Vector backbone
    pCR-Blunt II-TOPO
  • Backbone manufacturer
  • Backbone size w/o insert (bp) 3500
  • Vector type
    Mammalian Expression
  • Selectable markers

Growth in Bacteria

  • Bacterial Resistance(s)
  • Growth Temperature
  • Growth Strain(s)
  • Growth instructions
    However, plasmid yield and stability is improved when grown at 30 degrees.
  • Copy number

Sequence Information


  • Gene/Insert name
  • Alt name
  • Alt name
  • Insert Size (bp)

Cloning Information

Resource Information

  • Terms and Licenses

Depositor Comments

Plasmid containing FRT-STOP-FRT cassette for use in expressing genes only after Flp-mediated recombination.

It's like the LSL cassette ( but this one is a FSF cassette

How to cite this plasmid

These plasmids were created by your colleagues. Please acknowledge the Principal Investigator, cite the article in which the plasmids were described, and include Addgene in the Materials and Methods of your future publications.

  • For your Materials & Methods section:

    Fret-Stop-Fret TOPO was a gift from Tyler Jacks (Addgene plasmid # 22774)
  • For your References section:

    Analysis of lung tumor initiation and progression using conditional expression of oncogenic K-ras. Jackson EL, Willis N, Mercer K, Bronson RT, Crowley D, Montoya R, Jacks T, Tuveson DA. Genes Dev. 2001 Dec 15. 15(24):3243-8. 10.1101/gad.943001 PubMed 11751630