Introduction: In innate immunity, the immune receptor FLAGELLIN SENSITIVE-2 is regarded as the best model to study the functional properties of other receptors. Flagellin, the main building block of the bacterial flagellum, acts as a pathogen-associated molecular pattern (PAMPs) triggering the innate immune response in animals and plants. In Arabidopsis thaliana, the Leucine-rich repeat transmembrane receptor kinase FLS2 is essential for flagellin perception. Demonstrate the specific interaction of the elicitor-active epitope flg22 with the ectodomain of the FLS2 receptor by chemical cross-linking and immunoprecipitation. FLS2 constitutes the pattern-recognition receptor that determines the high specificity of flagellin perception. Due to the important role of FLS2 in the defense system, it is important to investigate the secondary and tertiary structure of this receptor. Predicting of the secondary and tertiary structure of proteins is very important in subsequent protein studies and the study and identification of the function of unknown proteins. Predicting the tertiary structure of proteins can also be used in molecular docking.
Methods: In this study, the Phyre2 software was used to investigate the secondary structure of the FLS2 protein. Three-dimensional structure modeling was performed based on the selection of a pattern with a high resemblance to the target protein using the Swiss Model database.
Results: The results indicate that five similar structures were found in the protein database for FLS2, one of these structures, called the crystal structure of a c20f3A, had a similarity of 95%. The model chosen for modeling FLS2 protein in Protein BRASSINOSTEROID INSENSITIVE 1 (Plant steroid receptor ectodomain bound to brassinolide and SERK1 co-receptor ectodomain) (4lsx.1.A) contains 774 amino acids and discovered by X-RAY DIFFRACTION with a resolution of 3.30 angstroms The Identity of 4lsx.1.A pattern with target, protein is 30.78.
Conclusion: The results of this research can be used in future research and molecular docking and provide basic information to investigate other immune receptors.
Keywords: Receptor, FLS2, 3D structure, 2D structure, Swiss Model Phyre2, Docking