Cell Signaling Technology

Product Pathways - TGF-beta/Smad Signaling

SignalSilence® Smad1 siRNA I #6223

Applications Reactivity
Transfection H

Reactivity Key:  H=Human
Species cross-reactivity is determined by western blot. Species enclosed in parentheses are predicted to react based on 100% sequence homology.

Western Blotting

Western Blotting

Western blot analysis of extracts from ACHN cells, transfected with 100 nM SignalSilence® Control siRNA (Unconjugated) #6568 (-), SignalSilence® Smad1 siRNA I (+), or SignalSilence® Smad1 siRNA II #6227 (+) using Smad1 (D59F7) XP® Rabbit mAb #6944 (upper) or α-Tubulin (11H10) Rabbit mAb #2125 (lower). The Smad1 (D59F7) XP® Rabbit mAb confirms silencing of Smad1 expression, while the α-Tubulin (11H10) Rabbit mAb is used as a loading control.

Description

SignalSilence® Smad1 siRNA I from Cell Signaling Technology (CST) allows the researcher to specifically inhibit Smad1 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.

Quality Control

Oligonucleotide synthesis is monitored base by base through trityl analysis to ensure appropriate coupling efficiency. The oligo is subsequently purified by affinity-solid phase extraction. The annealed RNA duplex is further analyzed by mass spectrometry to verify the exact composition of the duplex. Each lot is compared to the previous lot by mass spectrometry to ensure maximum lot-to-lot consistency.

Directions for Use

CST recommends transfection with 100 nM SignalSilence® Smad1 siRNA I 48 to 72 hours prior to cell lysis. For transfection procedure, follow protocol provided by the transfection reagent manufacturer. Please feel free to contact CST with any questions on use.

Each vial contains the equivalent of 100 transfections, which corresponds to a final siRNA concentration of 100 nM per transfection in a 24-well plate with a total volume of 300 μl per well.

Background

Bone morphogenetic proteins (BMPs) constitute a large family of signaling molecules that regulate a wide range of critical processes including morphogenesis, cell-fate determination, proliferation, differentiation, and apoptosis (1,2). BMP receptors are members of the TGF-β family of Ser/Thr kinase receptors. Ligand binding induces multimerization, autophosphorylation, and activation of these receptors (3-5). They subsequently phosphorylate Smad1 at Ser463 and Ser465 in the carboxy-terminal motif SSXS, as well as Smad5 and Smad8 at their corresponding sites. These phosphorylated Smads dimerize with the coactivating Smad4 and translocate to the nucleus, where they stimulate transcription of target genes (5).MAP kinases and CDKs 8 and 9 phosphorylate residues in the linker region of Smad1, including Ser206. The phosphorylation of Ser206 recruits Smurf1 to the linker region and leads to the degradation of Smad1 (6). Phosphorylation of this site also promotes Smad1 transcriptional action by recruiting YAP to the linker region (7).

  1. Hogan, B.L. et al. (1996) Genes Dev. 10, 1580-1594.
  2. Hoodless, P.A. et al. (1996) Cell 85, 489-500.
  3. Klemm, J.D. et al. (1998) Annu. Rev. Immunol. 16, 569-592.
  4. Kretzschmar, M. et al. (1997) Genes Dev. 11, 984-995.
  5. Whitman, M. (1998) Genes Dev. 12, 2445-2462.
  6. Sapkota, G. et al. (2007) Mol Cell 25, 441-54.
  7. Alarcón, C. et al. (2009) Cell 139, 757-69.

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.

For Research Use Only. Not For Use In Diagnostic Procedures.

Products