@article{OrawetzMalinovaOrzechowskietal.2016,
  author    = {Orawetz, Tom and Malinova, Irina and Orzechowski, Slawomir and Fettke, J{\"o}rg},
  title     = {Reduction of the plastidial phosphorylase in potato (Solanum tuberosum L.) reveals impact on storage starch structure during growth at low temperature},
  series = {Plant physiology and biochemistry : an official journal of the Federation of European Societies of Plant Physiology},
  volume    = {100},
  journal   = {Plant physiology and biochemistry : an official journal of the Federation of European Societies of Plant Physiology},
  publisher = {Elsevier},
  address   = {Paris},
  issn      = {0981-9428},
  doi       = {10.1016/j.plaphy.2016.01.013},
  pages     = {141 -- 149},
  year      = {2016},
  abstract  = {Tubers of potato (Solanum tuberosum L.), one of the most important crops, are a prominent example for an efficient production of storage starch. Nevertheless, the synthesis of this storage starch is not completely understood. The plastidial phosphorylase (Phol; EC 2.4.11) catalyzes the reversible transfer of glucosyl residues from glucose-1-phosphate to the non-reducing end of alpha-glucans with the release of orthophosphate. Thus, the enzyme is in principle able to act during starch synthesis. However, so far under normal growth conditions no alterations in tuber starch metabolism were observed. Based on analyses of other species and also from in vitro experiments with potato tuber slices it was supposed, that Phol has a stronger impact on starch metabolism, when plants grow under low temperature conditions. Therefore, we analyzed the starch content, granule size, as well as the internal structure of starch granules isolated from potato plants grown under low temperatures. Besides wild type, transgenic potato plants with a strong reduction in the Phol activity were analyzed. No significant alterations in starch content and granule size were detected. In contrast, when plants were cultivated at low temperatures the chain length distributions of the starch granules were altered. Thus, the granules contained more short glucan chains. That was not observed in the transgenic plants, revealing that Pho1 in wild type is involved in the formation of the short glucan chains, at least at low temperatures. (C) 2016 Elsevier Masson SAS. All rights reserved.},
  language  = {en}
}
@article{ZhangSunFettkeetal.2014,
  author    = {Zhang, Youjun and Sun, Feng and Fettke, J{\"o}rg and Schoettler, Mark Aurel and Ramsden, Lawrence and Fernie, Alisdair R. and Lim, Boon Leong},
  title     = {Heterologous expression of AtPAP2 in transgenic potato influences carbon metabolism and tuber development},
  series = {FEBS letters : the journal for rapid publication of short reports in molecular biosciences},
  volume    = {588},
  journal   = {FEBS letters : the journal for rapid publication of short reports in molecular biosciences},
  number    = {20},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0014-5793},
  doi       = {10.1016/j.febslet.2014.08.019},
  pages     = {3726 -- 3731},
  year      = {2014},
  abstract  = {Changes in carbon flow and sink/source activities can affect floral, architectural, and reproductive traits of plants. In potato, overexpression (OE) of the purple acid phosphatase 2 of Arabidopsis (AtPAP2) resulted in earlier flowering, faster growth rate, increased tubers and tuber starch content, and higher photosynthesis rate. There was a significant change in sucrose, glucose and fructose levels in leaves, phloem and sink biomass of the OE lines, consistent with an increased expression of sucrose transporter 1 (StSUT1). Furthermore, the expression levels and enzyme activity of sucrose-phosphate synthase (SPS) were also significantly increased in the OE lines. These findings strongly suggest that higher carbon supply from the source and improved sink strength can improve potato tuber yield. (C) 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{LicausiGiorgiSchmaelzlinetal.2011,
  author    = {Licausi, Francesco and Giorgi, Federico Manuel and Schmaelzlin, Elmar and Usadel, Bj{\"o}rn and Perata, Pierdomenico and van Dongen, Joost Thomas and Geigenberger, Peter},
  title     = {HRE-Type Genes are regulated by Growth-Related Changes in internal Oxygen Concentrations During the normal development of Potato (Solanum tuberosum) Tubers},
  series = {Plant \& cell physiology},
  volume    = {52},
  journal   = {Plant \& cell physiology},
  number    = {11},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {0032-0781},
  doi       = {10.1093/pcp/pcr128},
  pages     = {1957 -- 1972},
  year      = {2011},
  abstract  = {The occurrence of hypoxic conditions in plants not only represents a stress condition but is also associated with the normal development and growth of many organs, leading to adaptive changes in metabolism and growth to prevent internal anoxia. Internal oxygen concentrations decrease inside growing potato tubers, due to their active metabolism and increased resistance to gas diffusion as tubers grow. In the present work, we identified three hypoxia-responsive ERF (StHRE) genes whose expression is regulated by the gradual decrease in oxygen tensions that occur when potato tubers grow larger. Increasing the external oxygen concentration counteracted the modification of StHRE expression during tuber growth, supporting the idea that the actual oxygen levels inside the organs, rather than development itself, are responsible for the regulation of StHRE genes. We identified several sugar metabolism-related genes co-regulated with StHRE genes during tuber development and possibly involved in starch accumulation. All together, our data suggest a possible role for low oxygen in the regulation of sugar metabolism in the potato tuber, similar to what happens in storage tissues during seed development.},
  language  = {en}
}