Catalog Number: 4025
Chemical Name: cyclo[L-Asparaginyl-4-hydroxy-L-proly-(R-4,5-dihydroxy-L-isoleucyl-6-hydroxy-2-mercapto-L-tryptophylglycyl-L-isoleucylglycyl-L-cysteinyl]cyclic (4→8)-sulfide (R)-S-oxide
Biological Activity
Inhibitor of RNA polymerase II. Inhibits transcription in eukaryotic cells. Binds and blocks the largest subunits of RNA polymerase II, preventing new ribonucleotides from incorporating into the nascent RNA chain. Potent amatoxin.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 5 mM in ethanol and to 5 mM in water
  • Purity:
  • Storage:
    Store at -20°C
  • CAS No:
The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis. All Tocris products are intended for laboratory research use only.
Background References
  1. The transcriptional inhibitors, actinomycin D and α-amanitin, activate the HIV-1 promoter and favor phosphorylation of the RNA polymerase II C-terminal domain.
    Casse et al.
    J.Biol.Chem., 1999;274:16097
  2. Close association of RNA polymerase II and many transcription factors with Pol III genes.
    Raha et al.
    Proc.Natl.Acad.Sci., 2010;107:3639

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