187-1, N-WASP inhibitor peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

The cyclic peptide 187-1 is a 14-amino acid inhibitor identified through a high-throughput screen targeting actin polymerization pathways. This compound specifically binds to N-WASP (Neural Wiskott-Aldrich Syndrome Protein), a key regulator of actin cytoskeleton dynamics. By allosterically stabilizing the autoinhibited conformation of N-WASP, 187-1 prevents its interaction with the Arp2/3 complex, thereby blocking PIP₂-induced actin assembly. Biochemical assays and photo-crosslinking studies confirm that 187-1 directly interacts with N-WASP, demonstrating its role as a selective modulator of protein-protein interactions.

Structural analysis reveals that 187-1, a cyclodimeric peptide, exhibits high binding affinity for N-WASP, with an IC₅₀ of ~2 μM in inhibiting actin polymerization. Unlike linear peptides, its cyclic structure confers proteolytic stability and enhances target specificity. The inhibitory mechanism involves competition with activators such as cdc42, reinforcing the autoinhibited state of N-WASP. This peptide provides a valuable tool for probing N-WASP-dependent signaling pathways and elucidating the structural basis of allosteric inhibition in cytoskeletal regulation.

• Peterson JR, Lokey RS, Mitchison TJ, Kirschner MW. A chemical inhibitor of N-WASP reveals a new mechanism for targeting protein interactions. Proc Natl Acad Sci U S A. 2001 Sep 11;98(19):10624-9. doi: 10.1073/pnas.201393198. PMID: 11553809; PMCID: PMC58516.

Trifluoroacetic acid (TFA) is a common counterion from the purification process using High-Performance Liquid Chromatography (HPLC). The presence of TFA can affect the peptide's net weight, appearance, and solubility.

Impact on Net Weight: The TFA salt contributes to the total mass of the product. In most cases, the peptide content constitutes >80% of the total weight, with TFA accounting for the remainder.

Solubility: TFA salts generally enhance the solubility of peptides in aqueous solutions.

In Biological Assays: For most standard in vitro assays, the residual TFA levels do not cause interference. However, for highly sensitive cellular or biochemical studies, please be aware of its presence.