Description
Technical Information & Resources
Frequently Asked Questions
How should TrailBio® SB-431542 stock solutions be prepared?
TrailBio® SB-431542 is highly hydrophobic and insoluble in water, therefore use DMSO (<50 mg/ml) or Ethanol (<11 mg/ml) for stock solutions. When preparing stock solutions, ensure the final dilution of DMSO in your working media results in a concentration at or below 0.1% (v/v) to prevent cellular toxicity.
How selective is TrailBio® SB-431542 for ALK4/ALK5/ALK7?
TrailBio® SB-431542 targets ALK4 (IC50 = 1 µM), ALK5 (IC50 = 0.75 µM), and ALK7 (IC50 = 2 µM), but not the highly related BMP type I receptors ALK1, ALK2, ALK3, or ALK6. Inhibition of these receptors would require additional small molecule supplementation.
What concentration of TrailBio® SB-431542 should I use?
TrailBio® SB-431542 concentration should be optimized based on the cell type, protocol, and experimental objective. Its reported IC50 values are approximately 1 µM for ALK4, 0.75 µM for ALK5, and 2 µM for ALK7, so working concentrations should be selected to support the intended level of pathway inhibition while minimizing off-target effects.
Supporting Publications
Laping et al. (2002), Molecular Pharmacology
- This paper establishes SB-431542 as a novel TGF-β type I receptor/ALK5 kinase inhibitor and reports selective inhibition of Smad3 phosphorylation.
Inman et al. (2002), Molecular Pharmacology
- This paper defines the broader ALK4/ALK5/ALK7 specificity and shows selective inhibition of activin/TGF-β signaling without affecting BMP signaling, ERK, JNK, or p38 MAPK pathways.
Halder et al. (2005), Neoplasia
- This paper shows that SB-431542 blocks TGF-β-induced transcription, gene expression, apoptosis, growth suppression, EMT, motility, migration, invasion, and VEGF secretion across human cancer cell lines.
