Product Description | GKSWVSPAERYAVVPDETGLTDGSSKG (UVR8 C-terminal 27-residue fragment). The peptide corresponds to amino acids 397–423 of the UV-B photoreceptor protein UVR8 in Arabidopsis thaliana, commonly denoted as UVR8^C27. UVR8 operates as a UV-B-specific photoreceptor that exists as an inactive homodimer under normal conditions. Upon absorption of UV-B light, UVR8 monomerizes and interacts with the E3 ubiquitin ligase COP1, initiating UV-B signaling and photomorphogenic development. The UVR8 C-terminal 27-residue segment alone is sufficient to sustain the interaction with COP1 and regulate UV-B-dependent responses. Functional & Experimental Applications - Despite being intrinsically disordered, UVR8^C27 adopts more structured conformations at elevated temperatures, as observed via CD spectroscopy and NMR studies.
- Computational simulations revealed an inverted free energy landscape: the peptide’s lowest-energy state is disordered, yet structured conformations are accessible at higher energies.
- A key proline residue at position 411 (P411) plays a critical role in stabilizing this disordered, low-energy state and acts as a structural barrier that prevents α-helix propagation from the C-terminus inward.
- UVR8^C27 functions as a molecular switch, with its conformational flexibility enabling interaction with COP1 and facilitating UV-B signal transduction.
This peptide exemplifies how structural disorder and intrinsic flexibility serve as adaptative features for protein–protein interactions in cellular signaling pathways, specifically enabling UVR8 to act as a dynamic photoreceptor module. |
Scientific Background | Ac-GKSWVSPAERYAVVPDETGLTDGSSKG-NH2 is a 31-residue synthetic peptide with the sequence Ala-Cys-Gly-Lys-Ser-Trp-Val-Ser-Pro-Ala-Glu-Arg-Tyr-Ala-Val-Val-Pro-Asp-Glu-Thr-Gly-Leu-Thr-Asp-Gly-Ser-Ser-Lys-Gly-Asn-His. N-terminal acetylation neutralizes the terminal alpha-amino group; C-terminal amidation removes the terminal carboxylate charge. The sequence contains 1 cysteine residue, which can support thiol-selective conjugation or disulfide chemistry when the thiol group is available; is enriched in basic residues (2 Lys and 1 Arg), giving the sequence a cationic character under many aqueous conditions. No specific receptor, enzyme, pathway, disease association, or biological activity is assigned to this peptide without product-specific experimental evidence. |
Experimental Notes | Sequence-derived chemical properties are provided to support reagent selection and experimental planning. They do not establish a biological function. Solubility, aggregation, adsorption, conjugation efficiency, and assay performance should be validated under the intended experimental conditions. |
