The lysine-rich motif of intrinsically disordered stress protein CDeT11-24 from Craterostigma plantagineum is responsible for phosphatidic acid binding and protection of enzymes from damaging effects caused by desiccation.
The late embryogenesis abundant (LEA)-like protein CDeT11-24 is one of the major desiccation-related phosphoproteins of the resurrection plant Craterostigma plantagineum. In this study, it was shown that CDeT11-24 is mostly intrinsically disordered and protects two different enzymes, citrate synthase and lactate dehydrogenase, against damaging effects caused by desiccation. Lipid-binding assays revealed that CDeT11-24 is able to interact with phosphatidic acid, although electrostatic repulsion was expected due to the overall negative net charge of the protein under the tested physiological conditions. CDeT11-24 carries an N-terminal lysine-rich sequence, which is predicted to form an amphipathic α-helix. Analysis of the truncated CDeT11-24 protein identified this region to be responsible for both activities: enzyme protection and phosphatidic acid interaction. Possible functions of the CDeT11-24 protein are discussed in the context of desiccation tolerance.
Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, 53115 Bonn, Germany.
Jan
J
Petersen
Sylvia K
SK
Eriksson
Pia
P
Harryson
Steffen
S
Pierog
Thomas
T
Colby
Dorothea
D
Bartels
Horst
H
Röhrig
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002950:Citrate (si)-Synthase / Q000378:metabolism; D032181:Craterostigma / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003890:Desiccation; D057075:Enzyme Assays; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008954:Models, Biological; D016297:Mutagenesis, Site-Directed; D010712:Phosphatidic Acids / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins; D016415:Sequence Alignment; D015398:Signal Transduction; D014867:Water / Q000502:physiology
D010712:Phosphatidic Acids; D010940:Plant Proteins; D011994:Recombinant Proteins; C066246:late embryogenesis abundant protein, plant; D014867:Water; D007770:L-Lactate Dehydrogenase; D002950:Citrate (si)-Synthase