Cyclo[-RGDy-K(5-FAM)]

Product Name: Cyclo[-RGDy-K(5-FAM)]

Sequence One Letter Code: Cyclo[-RGDy-K(5-FAM)]

Sequence Three Letter Code: Cyclo[-Arg-Gly-Asp-D-Tyr-Lys(5-FAM)]

Molecular Weight: 978

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C Protected from light

Research Area: Cancer Disease Research

Source / Species: synthetic

Conjugation: Conjugated

Conjugation Type: Fluorescent dyes

Code Nacres: NA.26

Application: Cyclo[-RGDy-K(5-FAM)] is a fluorescently labeled cyclic RGD peptide engineered for high-affinity targeting of αv-integrins. The RGD sequence is a well-established ligand motif recognized by several integrin receptors that regulate cell adhesion, angiogenesis, and tumor progression. Cyclization of the peptide enhances structural stability, improves binding affinity to integrins, and increases resistance to proteolytic degradation. The incorporation of the 5-carboxyfluorescein (5-FAM) fluorophore enables sensitive fluorescence detection, allowing visualization and quantitative analysis in binding assays, cellular imaging, and uptake studies. This peptide is widely applied in cancer biology, angiogenesis research, and integrin-mediated signaling studies, and it is frequently used for evaluating integrin-targeted therapeutics, anti-angiogenic strategies, and tumor-targeting delivery systems.

Current Research: Integrins are a family of transmembrane receptors that play essential roles in cell adhesion, migration, angiogenesis, and signal transduction. Among them, αv-integrins—such as αvβ3 and αvβ5—are widely studied due to their involvement in tumor progression, vascular development, and metastasis. The ability to selectively target these receptors has become important for both basic research and therapeutic development. Cyclo[-RGDy-K(5-FAM)] is a fluorescently labeled cyclic RGD peptide designed for high-affinity targeting of αv-integrins. The peptide incorporates the arginine–glycine–aspartic acid (RGD) motif, a well-established ligand sequence recognized by several integrin receptors. In addition, the peptide is cyclized to enhance structural stability and binding efficiency, while the 5-carboxyfluorescein (5-FAM) fluorophore allows sensitive fluorescence detection in a variety of experimental applications. The RGD Motif and Integrin Recognition The RGD sequence is one of the most widely studied cell adhesion motifs in extracellular matrix proteins. It is found in several natural ligands, including fibronectin, vitronectin, fibrinogen, and osteopontin, where it mediates binding to integrin receptors on the cell surface. Integrins recognize the RGD motif through their extracellular domains, enabling cells to interact with the surrounding extracellular matrix (ECM). These interactions regulate key biological processes such as: Cell adhesion and migration Cell survival signaling Tissue remodeling Angiogenesis Certain integrins, particularly αvβ3 and αvβ5, are frequently overexpressed in tumor cells and in endothelial cells within newly forming blood vessels. Because of their role in tumor growth and angiogenesis, these integrins have become important targets for cancer research and drug development. Advantages of Cyclic RGD Peptides Many integrin-targeting peptides are designed with a cyclic structure, which offers several advantages compared with linear peptides. Cyclization restricts the peptide’s conformation, helping to maintain the RGD motif in an orientation that is optimal for integrin binding. This structural constraint often leads to: Improved binding affinity for integrin receptors Greater structural stability Increased resistance to enzymatic degradation As a result, cyclic RGD peptides frequently demonstrate stronger and more selective interactions with integrins than their linear counterparts. These properties make them highly useful in biological studies involving integrin-mediated signaling. Fluorescent Labeling with 5-Carboxyfluorescein (5-FAM) A key feature of Cyclo[-RGDy-K(5-FAM)] is the incorporation of the 5-carboxyfluorescein (5-FAM) fluorophore. 5-FAM is a widely used fluorescent dye known for its high quantum yield and compatibility with common fluorescence detection systems. When excited by visible light, 5-FAM emits strong green fluorescence, making it suitable for microscopy, flow cytometry, and fluorescence-based binding assays. In this peptide, the fluorophore is attached through the lysine side chain, allowing the RGD motif to remain accessible for receptor binding. The fluorescent label enables researchers to visualize and quantify peptide binding to integrin-expressing cells and tissues. This capability is particularly useful for studying receptor distribution, ligand uptake, and receptor-mediated internalization. Applications in Integrin and Cancer Research Because αv-integrins are associated with tumor growth and angiogenesis, fluorescent cyclic RGD peptides are widely used in cancer biology and vascular research. Cyclo[-RGDy-K(5-FAM)] supports a variety of experimental applications aimed at understanding integrin-mediated processes. Cellular Imaging The fluorescent signal provided by 5-FAM allows visualization of peptide binding in live-cell imaging and fluorescence microscopy. Researchers can track integrin localization on cell surfaces and observe receptor-mediated peptide uptake. Binding and Competition Assays The peptide can be used in fluorescence-based binding assays to measure integrin affinity and evaluate the effectiveness of integrin inhibitors. Competition experiments can reveal how candidate therapeutics interfere with RGD–integrin interactions. Angiogenesis Studies Integrins such as αvβ3 play a major role in the formation of new blood vessels. Fluorescent RGD peptides enable researchers to monitor integrin activity in angiogenic endothelial cells, providing insight into vascular development and anti-angiogenic therapies. Evaluation of Integrin-Targeted Therapeutics Cyclo[-RGDy-K(5-FAM)] is frequently used to assess integrin-targeted drug delivery systems and therapeutic strategies designed to block integrin signaling in tumors. By labeling integrin-binding peptides with fluorescent markers, researchers can study targeting efficiency and cellular uptake. Tumor Targeting Research Because integrin expression is often elevated in tumor tissues, RGD-based peptides are widely used to investigate tumor-targeting approaches, including nanoparticle delivery systems and imaging agents. Supporting Research on Integrin-Mediated Signaling Integrin receptors serve as critical mediators between cells and the extracellular environment. Understanding how these receptors interact with ligands such as the RGD motif is essential for unraveling the molecular mechanisms that control cell migration, angiogenesis, and tumor progression. The Cyclo[-RGDy-K(5-FAM)] peptide combines a high-affinity cyclic RGD ligand with a sensitive fluorescent probe, providing a powerful tool for studying integrin biology. Through applications in cellular imaging, receptor binding assays, and therapeutic evaluation, this peptide helps researchers explore how integrin signaling pathways contribute to cancer development and vascular remodeling.