Species predicted to react based on 100% sequence homology:Rat, Monkey
Specificity / Sensitivity
SignalSilence®Smad4 siRNA I (Mouse Specific) inhibits mouse, rat, and monkey Smad4 expression.
Description
SignalSilence®Smad4 siRNA I (Mouse Specific) from Cell Signaling Technology (CST) allows the researcher to specifically inhibit Smad4 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® Smad4 siRNA I (Mouse Specific) 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
Members of the Smad family of signal transduction molecules are components of a critical intracellular pathway that transmits TGF-β signals from the cell surface into the nucleus. Three distinct classes of Smads have been defined: the recepter-regulated Smads (R-Smads), which include Smad1, 2, 3, 5, 8; the common-mediator Smad (co-Smad), Smad4; and the antagonistic or inhibitory Smads (I-Smads), Smad6 and 7 (1-5). Briefly, activated type I receptors associate with specific R-Smads and phosphorylate them on a conserved SSXS motif at the carboxy-terminus of the proteins. The phosphorylated R-Smad dissociates from the receptor and forms a heteromeric complex with the co-Smad, Smad4, and together the complex moves to the nucleus. Once in the nucleus, Smads can target a variety of DNA binding proteins to regulate transcriptional responses (6-8).