@article{SprengerErbanSeddigetal.2017,
  author    = {Sprenger, Heike and Erban, Alexander and Seddig, Sylvia and Rudack, Katharina and Thalhammer, Anja and Le, Mai Q. and Walther, Dirk and Zuther, Ellen and Koehl, Karin I. and Kopka, Joachim and Hincha, Dirk K.},
  title     = {Metabolite and transcript markers for the prediction of potato drought tolerance},
  series = {Plant Biotechnology Journal},
  volume    = {16},
  journal   = {Plant Biotechnology Journal},
  number    = {4},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1467-7644},
  doi       = {10.1111/pbi.12840},
  pages     = {939 -- 950},
  year      = {2017},
  abstract  = {Potato (Solanum tuberosum L.) is one of the most important food crops worldwide. Current potato varieties are highly susceptible to drought stress. In view of global climate change, selection of cultivars with improved drought tolerance and high yield potential is of paramount importance. Drought tolerance breeding of potato is currently based on direct selection according to yield and phenotypic traits and requires multiple trials under drought conditions. Marker-assisted selection (MAS) is cheaper, faster and reduces classification errors caused by noncontrolled environmental effects. We analysed 31 potato cultivars grown under optimal and reduced water supply in six independent field trials. Drought tolerance was determined as tuber starch yield. Leaf samples from young plants were screened for preselected transcript and nontargeted metabolite abundance using qRT-PCR and GC-MS profiling, respectively. Transcript marker candidates were selected from a published RNA-Seq data set. A Random Forest machine learning approach extracted metabolite and transcript markers for drought tolerance prediction with low error rates of 6\% and 9\%, respectively. Moreover, by combining transcript and metabolite markers, the prediction error was reduced to 4.3\%. Feature selection from Random Forest models allowed model minimization, yielding a minimal combination of only 20 metabolite and transcript markers that were successfully tested for their reproducibility in 16 independent agronomic field trials. We demonstrate that a minimum combination of transcript and metabolite markers sampled at early cultivation stages predicts potato yield stability under drought largely independent of seasonal and regional agronomic conditions.},
  language  = {en}
}
@misc{SprengerErbanSeddigetal.2018,
  author    = {Sprenger, Heike and Erban, Alexander and Seddig, Sylvia and Rudack, Katharina and Thalhammer, Anja and Le, Mai Q. and Walther, Dirk and Zuther, Ellen and K{\"o}hl, Karin I. and Kopka, Joachim and Hincha, Dirk K.},
  title     = {Metabolite and transcript markers for the prediction of potato drought tolerance},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {673},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-42463},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-424630},
  pages     = {12},
  year      = {2018},
  abstract  = {Potato (Solanum tuberosum L.) is one of the most important food crops worldwide. Current potato varieties are highly susceptible to drought stress. In view of global climate change, selection of cultivars with improved drought tolerance and high yield potential is of paramount importance. Drought tolerance breeding of potato is currently based on direct selection according to yield and phenotypic traits and requires multiple trials under drought conditions. Marker-assisted selection (MAS) is cheaper, faster and reduces classification errors caused by noncontrolled environmental effects. We analysed 31 potato cultivars grown under optimal and reduced water supply in six independent field trials. Drought tolerance was determined as tuber starch yield. Leaf samples from young plants were screened for preselected transcript and nontargeted metabolite abundance using qRT-PCR and GC-MS profiling, respectively. Transcript marker candidates were selected from a published RNA-Seq data set. A Random Forest machine learning approach extracted metabolite and transcript markers for drought tolerance prediction with low error rates of 6\% and 9\%, respectively. Moreover, by combining transcript and metabolite markers, the prediction error was reduced to 4.3\%. Feature selection from Random Forest models allowed model minimization, yielding a minimal combination of only 20 metabolite and transcript markers that were successfully tested for their reproducibility in 16 independent agronomic field trials. We demonstrate that a minimum combination of transcript and metabolite markers sampled at early cultivation stages predicts potato yield stability under drought largely independent of seasonal and regional agronomic conditions.},
  language  = {en}
}
@article{NavarroRetamalBremerAlzateMoralesetal.2016,
  author    = {Navarro-Retamal, Carlos and Bremer, Anne and Alzate-Morales, Jans H. and Caballero, Julio and Hincha, Dirk K. and Gonzalez, Wendy and Thalhammer, Anja},
  title     = {Molecular dynamics simulations and CD spectroscopy reveal hydration-induced unfolding of the intrinsically disordered LEA proteins COR15A and COR15B from Arabidopsis thaliana},
  series = {Physical chemistry, chemical physics : a journal of European Chemical Societies},
  volume    = {18},
  journal   = {Physical chemistry, chemical physics : a journal of European Chemical Societies},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1463-9076},
  doi       = {10.1039/c6cp02272c},
  pages     = {25806 -- 25816},
  year      = {2016},
  abstract  = {The LEA (late embryogenesis abundant) proteins COR15A and COR15B from Arabidopsis thaliana are intrinsically disordered under fully hydrated conditions, but obtain alpha-helical structure during dehydration, which is reversible upon rehydration. To understand this unusual structural transition, both proteins were investigated by circular dichroism (CD) and molecular dynamics (MD) approaches. MD simulations showed unfolding of the proteins in water, in agreement with CD data obtained with both HIS-tagged and untagged recombinant proteins. Mainly intramolecular hydrogen bonds (H-bonds) formed by the protein backbone were replaced by H-bonds with water molecules. As COR15 proteins function in vivo as protectants in leaves partially dehydrated by freezing, unfolding was further assessed under crowded conditions. Glycerol reduced (40\%) or prevented (100\%) unfolding during MD simulations, in agreement with CD spectroscopy results. H-bonding analysis indicated that preferential exclusion of glycerol from the protein backbone increased stability of the folded state.},
  language  = {en}
}
@misc{NavarroRetamalBremerAlzateMoralesetal.2016,
  author    = {Navarro-Retamal, Carlos and Bremer, Anne and Alzate-Morales, Jans H. and Caballero, Julio and Hincha, Dirk K. and Gonz{\´a}lez, Wendy and Thalhammer, Anja},
  title     = {Molecular dynamics simulations and CD spectroscopy reveal hydration-induced unfolding of the intrinsically disordered LEA proteins COR15A and COR15B from Arabidopsis thaliana},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-394503},
  pages     = {25806 -- 25816},
  year      = {2016},
  abstract  = {The LEA (late embryogenesis abundant) proteins COR15A and COR15B from Arabidopsis thaliana are intrinsically disordered under fully hydrated conditions, but obtain α-helical structure during dehydration, which is reversible upon rehydration. To understand this unusual structural transition, both proteins were investigated by circular dichroism (CD) and molecular dynamics (MD) approaches. MD simulations showed unfolding of the proteins in water, in agreement with CD data obtained with both HIS-tagged and untagged recombinant proteins. Mainly intramolecular hydrogen bonds (H-bonds) formed by the protein backbone were replaced by H-bonds with water molecules. As COR15 proteins function in vivo as protectants in leaves partially dehydrated by freezing, unfolding was further assessed under crowded conditions. Glycerol reduced (40\%) or prevented (100\%) unfolding during MD simulations, in agreement with CD spectroscopy results. H-bonding analysis indicated that preferential exclusion of glycerol from the protein backbone increased stability of the folded state.},
  language  = {en}
}
@article{HilkerSchwachtjeBaieretal.2016,
  author    = {Hilker, Monika and Schwachtje, Jens and Baier, Margarete and Balazadeh, Salma and B{\"a}urle, Isabel and Geiselhardt, Sven and Hincha, Dirk K. and Kunze, Reinhard and Mueller-Roeber, Bernd and Rillig, Matthias G. and Rolff, Jens and Schm{\"u}lling, Thomas and Steppuhn, Anke and van Dongen, Joost and Whitcomb, Sarah J. and Wurst, Susanne and Zuther, Ellen and Kopka, Joachim},
  title     = {Priming and memory of stress responses in organisms lacking a nervous system},
  series = {Biological reviews},
  volume    = {91},
  journal   = {Biological reviews},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1464-7931},
  doi       = {10.1111/brv.12215},
  pages     = {1118 -- 1133},
  year      = {2016},
  language  = {en}
}
@article{KnoxBrownRindfleischGuentheretal.2020,
  author    = {Knox-Brown, Patrick and Rindfleisch, Tobias and G{\"u}nther, Anne and Balow, Kim and Bremer, Anne and Walther, Dirk and Miettinen, Markus S. and Hincha, Dirk K. and Thalhammer, Anja},
  title     = {Similar Yet Different},
  series = {International Journal of Molecular Sciences},
  volume    = {21},
  journal   = {International Journal of Molecular Sciences},
  number    = {8},
  publisher = {Molecular Diversity Preservation International},
  address   = {Basel},
  issn      = {1422-0067},
  doi       = {10.3390/ijms21082794},
  pages     = {25},
  year      = {2020},
  abstract  = {The importance of intrinsically disordered late embryogenesis abundant (LEA) proteins in the tolerance to abiotic stresses involving cellular dehydration is undisputed. While structural transitions of LEA proteins in response to changes in water availability are commonly observed and several molecular functions have been suggested, a systematic, comprehensive and comparative study of possible underlying sequence-structure-function relationships is still lacking. We performed molecular dynamics (MD) simulations as well as spectroscopic and light scattering experiments to characterize six members of two distinct, lowly homologous clades of LEA_4 family proteins from Arabidopsis thaliana. We compared structural and functional characteristics to elucidate to what degree structure and function are encoded in LEA protein sequences and complemented these findings with physicochemical properties identified in a systematic bioinformatics study of the entire Arabidopsis thaliana LEA_4 family. Our results demonstrate that although the six experimentally characterized LEA_4 proteins have similar structural and functional characteristics, differences concerning their folding propensity and membrane stabilization capacity during a freeze/thaw cycle are obvious. These differences cannot be easily attributed to sequence conservation, simple physicochemical characteristics or the abundance of sequence motifs. Moreover, the folding propensity does not appear to be correlated with membrane stabilization capacity. Therefore, the refinement of LEA_4 structural and functional properties is likely encoded in specific patterns of their physicochemical characteristics.},
  language  = {en}
}
@misc{KnoxBrownRindfleischGuentheretal.2020,
  author    = {Knox-Brown, Patrick and Rindfleisch, Tobias and G{\"u}nther, Anne and Balow, Kim and Bremer, Anne and Walther, Dirk and Miettinen, Markus S. and Hincha, Dirk K. and Thalhammer, Anja},
  title     = {Similar Yet Different},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {901},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-46941},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-469419},
  pages     = {27},
  year      = {2020},
  abstract  = {The importance of intrinsically disordered late embryogenesis abundant (LEA) proteins in the tolerance to abiotic stresses involving cellular dehydration is undisputed. While structural transitions of LEA proteins in response to changes in water availability are commonly observed and several molecular functions have been suggested, a systematic, comprehensive and comparative study of possible underlying sequence-structure-function relationships is still lacking. We performed molecular dynamics (MD) simulations as well as spectroscopic and light scattering experiments to characterize six members of two distinct, lowly homologous clades of LEA_4 family proteins from Arabidopsis thaliana. We compared structural and functional characteristics to elucidate to what degree structure and function are encoded in LEA protein sequences and complemented these findings with physicochemical properties identified in a systematic bioinformatics study of the entire Arabidopsis thaliana LEA_4 family. Our results demonstrate that although the six experimentally characterized LEA_4 proteins have similar structural and functional characteristics, differences concerning their folding propensity and membrane stabilization capacity during a freeze/thaw cycle are obvious. These differences cannot be easily attributed to sequence conservation, simple physicochemical characteristics or the abundance of sequence motifs. Moreover, the folding propensity does not appear to be correlated with membrane stabilization capacity. Therefore, the refinement of LEA_4 structural and functional properties is likely encoded in specific patterns of their physicochemical characteristics.},
  language  = {en}
}
@article{PopovaHundertmarkSeckleretal.2011,
  author    = {Popova, Antoaneta V. and Hundertmark, Michaela and Seckler, Robert and Hincha, Dirk K.},
  title     = {Structural transitions in the intrinsically disordered plant dehydration stress protein LEA7 upon drying are modulated by the presence of membranes},
  series = {Biochimica et biophysica acta : Biomembranes},
  volume    = {1808},
  journal   = {Biochimica et biophysica acta : Biomembranes},
  number    = {7},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0005-2736},
  doi       = {10.1016/j.bbamem.2011.03.009},
  pages     = {1879 -- 1887},
  year      = {2011},
  abstract  = {Dehydration stress-related late embryogenesis abundant (LEA) proteins have been found in plants, invertebrates and bacteria. Most LEA proteins are unstructured in solution, but some fold into amphipathic a-helices during drying. The Pfam LEA_4 (Group 3) protein LEA7 from the higher plant Arabidopsis thaliana was predicted to be 87\% alpha-helical, while CD spectroscopy showed it to be largely unstructured in solution and only 35\% alpha-helical in the dry state. However, the dry protein contained 15\% beta-sheets. FTIR spectroscopy revealed the (beta-sheets to be largely due to aggregation. beta-Sheet content was reduced and alpha-helix content increased when LEA7 was dried in the presence of liposomes with secondary structure apparently influenced by lipid composition. Secondary structure was also affected by the presence of membranes in the fully hydrated state. A temperature-induced increase in the flexibility of the dry protein was also only observed in the presence of membranes. Functional interactions of LEA7 with membranes in the dry state were indicated by its influence on the thermotropic phase transitions of the lipids and interactions with the lipid headgroup phosphates.},
  language  = {en}
}
@article{HundertmarkDimovaLengefeldetal.2011,
  author    = {Hundertmark, Michaela and Dimova, Rumiana and Lengefeld, Jan and Seckler, Robert and Hincha, Dirk K.},
  title     = {The intrinsically disordered late embryogenesis abundant protein LEA18 from Arabidopsis thaliana modulates membrane stability through binding and folding},
  series = {Biochimica et biophysica acta : Biomembranes},
  volume    = {1808},
  journal   = {Biochimica et biophysica acta : Biomembranes},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0005-2736},
  doi       = {10.1016/j.bbamem.2010.09.010},
  pages     = {446 -- 453},
  year      = {2011},
  abstract  = {Intrinsically disordered proteins (IDPs) constitute a substantial part of cellular proteomes. late embryogenesis abundant (LEA) proteins are mostly predicted to be IDPs associated with dehydration tolerance in many plant, animal and bacterial species. Their functions, however, are largely unexplored and also their structure and interactions with potential target molecules have only recently been experimentally investigated in a small number of proteins. Here, we report on the structure and interactions with membranes of the Pfam LEA_1 protein LEA18 from the higher plant Arabidopsis thaliana. This functionally uncharacterized positively charged protein specifically aggregated and destabilized negatively charged liposomes. Isothermal titration calorimetry showed binding of the protein to both charged and uncharged membranes. LEA18 alone was largely unstructured in solution. While uncharged membranes had no influence on the secondary structure of LEA18, the protein partially folded into beta-sheet structure in the presence of negatively charged liposomes. These data suggest that LEA18 does not function as a membrane stabilizing protein, as suggested for other LEA proteins. Instead, a possible function of LEA18 could be the composition-dependent modulation of membrane stability, e.g., during signaling or vesicle-mediated transport.},
  language  = {en}
}
@article{HundertmarkDimovaLengefeldetal.2011,
  author    = {Hundertmark, Michaela and Dimova, Rumiana and Lengefeld, Jan and Seckler, Robert and Hincha, Dirk K.},
  title     = {The intrinsically disordered late embryogenesis abundant protein LEA18 from Arabidopsis thaliana modulates membrane stability through binding and folding.},
  issn      = {0006-3002},
  year      = {2011},
  abstract  = {Intrinsically disordered proteins (IDPs) constitute a substantial part of cellular proteomes. Late embryogenesis abundant (LEA) proteins are mostly predicted to be IDPs associated with dehydration tolerance in many plant, animal and bacterial species. Their functions, however, are largely unexplored and also their structure and interactions with potential target molecules have only recently been experimentally investigated in a small number of proteins. Here, we report on the structure and interactions with membranes of the Pfam LEA_1 protein LEA18 from the higher plant Arabidopsis thaliana. This functionally uncharacterized positively charged protein specifically aggregated and destabilized negatively charged liposomes. Isothermal titration calorimetry showed binding of the protein to both charged and uncharged membranes. LEA18 alone was largely unstructured in solution. While uncharged membranes had no influence on the secondary structure of LEA18, the protein partially folded into ;-sheet structure in the presence of negatively charged liposomes. These data suggest that LEA18 does not function as a membrane stabilizing protein, as suggested for other LEA proteins. Instead, a possible function of LEA18 could be the composition-dependent modulation of membrane stability, e.g., during signaling or vesicle-mediated transport. Research Highlights},
  language  = {en}
}