Low Resolution Structure of RAR1-GST-Tag Fusion Protein in Solution

RAR1 is a protein required for resistance mediated by many R genes and function upstream of signaling pathways leading to $H_{2}O_{2}$ accumulation. The structure and conformation of RAR1-GST-Tag fusion protein from barley (Hordeum vulgare) in solution was studied by the small angle scattering of synchrotron radiation. It was found that the dimer of RAR1-GST-Tag protein is characterized in solution by radius of gyration $R_G$ = 6.19 nm and maximal intramolecular vector $D_{max}$ = 23 nm. On the basis of the small angle scattering of synchrotron radiation SAXS data two bead models obtained by ab initio modeling are proposed. Both models show elongated conformations. We also concluded that molecules of fusion protein form dimers in solution via interaction of GST domains.