PTEN antagonist peptide (PAP4)

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

Batch to batch variation of the purity

PTEN antagonist peptide (PAP4) is a 30-amino acid peptide designed to bind the C-terminal portion of phosphatase and tensin homolog (PTEN), a neuronal-intrinsic inhibitor of the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway that regulates axon growth. Through this binding interaction, PAP4 inhibits PTEN activity, thereby relieving the intrinsic suppression of axon growth capacity in neurons. The peptide is capable of crossing the blood-brain barrier, allowing for systemic delivery.

In studies using a rat model of chronic cervical contusion spinal cord injury, systemic administration of PAP4 promoted robust growth of descending bulbospinal axons originating from the rostral ventral respiratory group (rVRG) caudal to the injury site within the denervated portion of the phrenic motor neuron pool. This axon growth was associated with partial recovery of diaphragm motor activity. The growth-promoting effects of PAP4 on rVRG axons were observed specifically at locations critical for控制 of diaphragmatic respiratory function, with a five- to eight-fold increase in labeled rVRG axon profiles and total axon length compared to control conditions. The peptide's actions were attributed to its capacity to modulate neuron-intrinsic axon growth potential by targeting PTEN-mediated signaling.

• Ohtake Y, Park D, Muneer PMA, Li H, Xu B, Sharma K, Smith GM, Selzer ME, Li S. The effect of systemic PTEN antagonist peptides on axon growth and functional recovery after spinal cord injury. Biomaterials. 2014 May;35(16):4610-26. doi: 10.1016/j.biomaterials.2014.02.037. Epub 2014 Mar 12. PMID: 24630093; PMCID: PMC4195449.
• Michel-Flutot P, Cheng L, Thomas SJ, Lisi B, Schwartz H, Lam S, Lyttle M, Jaffe DA, Smith G, Li S, Wright MC, Lepore AC. PTEN inhibition promotes robust growth of bulbospinal respiratory axons and partial recovery of diaphragm function in a chronic model of cervical contusion spinal cord injury. Exp Neurol. 2024 Aug;378:114816. doi: 10.1016/j.expneurol.2024.114816. Epub 2024 May 22. PMID: 38789023; PMCID: PMC11200215.

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.