Folding of intrinsically disordered plant LEA proteins is driven by glycerol-induced crowding and the presence of membranes

摘要: Late embryogenesis abundant (LEA) proteins are related to cellular dehydration tolerance. Most LEA predicted have no stable secondary structure in solution, i.e., be intrinsically disordered (IDPs), but they may acquire α-helical upon drying. In the model plant Arabidopsis thaliana, COR15A and COR15B highly induced cold treatment necessary for plants attain full freezing Freezing leads increased intracellular crowding due by extracellular ice crystals. vitro, high glycerol concentrations partial folding of COR15 proteins. Here, we extended these investigations two proteins, LEA11 LEA25. LEA25 is much longer than COR15A, shares a conserved central sequence domain with other We created truncated versions (2H 4H) elucidate structural functional significance this domain. Light scattering CD spectroscopy showed that all five were largely unstructured monomeric dilute solution. They folded presence increasing trifluoroethanol glycerol. Additional was observed membranes. Fourier transform infra red revealed an interaction membranes dry state leading depression gel liquid-crystalline phase transition temperature. Liposome stability assays cryoprotective function The C- N-terminal extensions important cryoprotection, as itself (2H, only provided low level protection.