Cell Signaling Technology

Product Pathways - Jak/Stat Pathway

SignalSilence® Stat1 siRNA #6331

Western Blotting

Western Blotting

Western blot analysis of extracts from HeLa cells 48 hours following mock transfection, transfection with non-targeted (control) siRNA or transfection with Stat1 siRNA. Stat1 was detected using Stat1 Antibody #9172, and p42 was detected using p42 MAPK Antibody #9108. The Stat1 Antibody confirms silencing of Stat1 expression, and the p42 MAPK Antibody is used to control for protein loading and siRNA specificity.

Fluorescent Detection

Fluorescent Detection

Fluorescent detection of SignalSilence® Control siRNA (Fluorescein Conjugate) #6201 in living HeLa cells 24 hours post-transfection, demonstrating nearly 100% transfection efficiency.

Directions for Use

CST recommends transfection with 100 nM Stat1 siRNA. Decreased Stat1 expression was observed 24-72 hours post-transfection. See Protocol for transfection procedure.

Background

The Stat1 transcription factor is activated in response to a large number of ligands (1) and is essential for responsiveness to IFN-α and IFN-γ (2,3). Phosphorylation of Stat1 at Tyr701 induces Stat1 dimerization, nuclear translocation and DNA binding (4). Stat1 protein exists as a pair of isoforms, Stat1α (91 kDa) and the splice variant Stat1β (84 kDa). In most cells, both isoforms are activated by IFN-α, but only Stat1α is activated by IFN-γ. The inappropriate activation of Stat1 occurs in many tumors (5). In addition to tyrosine phosphorylation, Stat1 is also phosphorylated at Ser727 through a p38 mitogen-activated protein kinase (MAPK)-dependent pathway in response to IFN-α and other cellular stresses (6). Serine phosphorylation may be required for the maximal induction of Stat1-mediated gene activation.

  1. Heim, M.H. (1999) J. Recept. Signal. Transduct. Res. 19, 75-120.
  2. Durbin, J.E. et al. (1996) Cell 84, 443-450.
  3. Meraz, M.A. et al. (1996) Cell 84, 431-442.
  4. Ihle, J.N. et al. (1994) Trends Biochem. Sci. 19, 222-227.
  5. Frank, D.A. (1999) Mol. Med. 5, 432-456.
  6. Wen, Z. et al. (1995) Cell 82, 241-250.

Application References

Have you published research involving the use of our products? If so we'd love to hear about it. Please let us know!

Companion Products

Limited Use Label License, RNA interference: This product is licensed under European Patent 1144623 and foreign equivalents from Ribopharma AG, Kulmbach, Germany and is provided only for use in non-commercial research specifically excluding use (a) in drug discovery or drug development, including target identification or target validation, by or on behalf of a commercial entity, (b) for contract research or commercial screening services, (c) for the production or manufacture of siRNA-related products for sale, or (d) for the generation of commercial databases for sale to Third Parties. Information about licenses for these and other commercial uses is available from Ribopharma AG, Fritz-Hornschuch-Str. 9, D-95326 Kulmbach, Germany.

Product Pathways

Drug Discovery Tools

Featured Technologies

Protein Classes