TY  - JOUR
A1  - Zhang, Youjun
A1  - Sun, Feng
A1  - Fettke, Jörg
A1  - Schoettler, Mark Aurel
A1  - Ramsden, Lawrence
A1  - Fernie, Alisdair R.
A1  - Lim, Boon Leong
T1  - Heterologous expression of AtPAP2 in transgenic potato influences carbon metabolism and tuber development
JF  - FEBS letters : the journal for rapid publication of short reports in molecular biosciences
N2  - 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.
KW  - Potato
KW  - AtPAP2
KW  - Photosynthesis
KW  - Tuber yield
KW  - Sugar efflux
Y1  - 2014
U6  - https://doi.org/10.1016/j.febslet.2014.08.019
SN  - 0014-5793
SN  - 1873-3468
VL  - 588
IS  - 20
SP  - 3726
EP  - 3731
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Orawetz, Tom
A1  - Malinova, Irina
A1  - Orzechowski, Slawomir
A1  - Fettke, Jörg
T1  - Reduction of the plastidial phosphorylase in potato (Solanum tuberosum L.) reveals impact on storage starch structure during growth at low temperature
JF  - Plant physiology and biochemistry : an official journal of the Federation of European Societies of Plant Physiology
N2  - 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.
KW  - Potato
KW  - Solanum tuberosum L.
KW  - Plastidial phosphorylase
KW  - Starch synthase
KW  - Starch metabolism
KW  - Starch granule
Y1  - 2016
U6  - https://doi.org/10.1016/j.plaphy.2016.01.013
SN  - 0981-9428
VL  - 100
SP  - 141
EP  - 149
PB  - Elsevier
CY  - Paris
ER  -