11R-VEET peptide

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

Batch to batch variation of the purity

The 11R-VEET peptide is a synthetic, cell-permeable peptide designed as a control for studies of calcineurin-NFAT signaling interference. It is composed of an 11-arginine cell-penetrating peptide (11R) linked via a three-glycine linker to a scrambled version of the VIVIT peptide sequence (MAGPPHIVEETGPHVI). The 11R sequence facilitates translocation across cellular membranes. Unlike the active VIVIT peptide, which contains the high-affinity calcineurin-docking PxIxIT motif, the VEET sequence has the same amino acid residues rearranged in a scrambled order. This renders the 11R-VEET peptide incapable of specifically competing with the native NFAT PxIxIT motif for binding to calcineurin. Consequently, it does not affect calcineurin-dependent NFAT dephosphorylation, nuclear translocation, or transcriptional activity.

In experimental contexts, particularly in human glioma cells, the 11R-VEET peptide serves as a negative control. Its use allows researchers to distinguish specific effects of the active 11R-VIVIT peptide from non-specific effects, such as those potentially induced by the 11R transduction domain or general peptide uptake. The 11R-VEET peptide does not alter the subcellular localization of NFAT proteins (e.g., NFATc1, NFATc3), nor does it modulate the activity of NFAT-responsive promoters or the expression of endogenous NFAT target genes like COX2 and c-MYC, confirming its inert role in the calcineurin-NFAT pathway.

• Ellert-Miklaszewska A, Szymczyk A, Poleszak K, Kaminska B. Delivery of the VIVIT Peptide to Human Glioma Cells to Interfere with Calcineurin-NFAT Signaling. Molecules. 2021 Aug 7;26(16):4785. doi: 10.3390/molecules26164785. PMID: 34443374; PMCID: PMC8400789.
• Pereverzev A, Komarova SV, Korcok J, Armstrong S, Tremblay GB, Dixon SJ, Sims SM. Extracellular acidification enhances osteoclast survival through an NFAT-independent, protein kinase C-dependent pathway. Bone. 2008 Jan;42(1):150-61. doi: 10.1016/j.bone.2007.08.044. Epub 2007 Sep 14. PMID: 17964236.

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.