title: The Craterostigma plantagineum glycine-rich protein CpGRP1 interacts with a cell wall-associated protein kinase 1 (CpWAK1) and accumulates in leaf cell walls during dehydration.
abstract: Craterostigma plantagineum tolerates extreme desiccation. Leaves of this plant shrink and extensively fold during dehydration and expand again during rehydration, preserving their structural integrity. Genes were analysed that may participate in the reversible folding mechanism. Analysis of transcripts abundantly expressed in desiccated leaves identified a gene putatively coding for an apoplastic glycine-rich protein (CpGRP1). We studied the expression, regulation and subcellular localization of CpGRP1 and its ability to interact with a cell wall-associated protein kinase (CpWAK1) to understand the role of CpGRP1 in the cell wall during dehydration. The CpGRP1 protein accumulates in the apoplast of desiccated leaves. Analysis of the promoter revealed that the gene expression is mainly regulated at the transcriptional level, is independent of abscisic acid (ABA) and involves a drought-responsive cis-element (DRE). CpGRP1 interacts with CpWAK1 which is down-regulated in response to dehydration. Our data suggest a role of the CpGRP1-CpWAK1 complex in dehydration-induced morphological changes in the cell wall during dehydration in C. plantagineum. Cell wall pectins and dehydration-induced pectin modifications are predicted to be involved in the activity of the CpGRP1-CpWAK1 complex.
authors.affiliation: Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, Bonn, D-53115, Germany.
authors.forename: Valentino
authors.initials: V
authors.lastname: Giarola
authors.affiliation: Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, Bonn, D-53115, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Krey
authors.affiliation: Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, Bonn, D-53115, Germany.
authors.forename: Barbara
authors.initials: B
authors.lastname: von den Driesch
authors.affiliation: Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, Bonn, D-53115, Germany.
authors.forename: Dorothea
authors.initials: D
authors.lastname: Bartels
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000378:metabolism; D001483:Base Sequence; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism*; D032181:Craterostigma / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D003681:Dehydration; D015536:Down-Regulation / Q000187:drug effects; D055864:Droughts; D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005998:Glycine / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D008954:Models, Biological; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D011494:Protein Kinases / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D000040:Abscisic Acid; D011494:Protein Kinases; D005998:Glycine
keywords: Craterostigma plantagineum; cell wall-associated protein kinase; desiccation tolerance; glycine-rich protein; leaf folding; resurrection plants