Present address: School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
Overriding the co-limiting import of carbon and energy into tuber amyloplasts increases the starch content and yield of transgenic potato plants
Article first published online: 25 MAR 2008
© 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd
Plant Biotechnology Journal
Volume 6, Issue 5, pages 453–464, June 2008
How to Cite
Zhang, L., Häusler, R. E., Greiten, C., Hajirezaei, M.-R., Haferkamp, I., Neuhaus, H. E., Flügge, U.-I. and Ludewig, F. (2008), Overriding the co-limiting import of carbon and energy into tuber amyloplasts increases the starch content and yield of transgenic potato plants. Plant Biotechnology Journal, 6: 453–464. doi: 10.1111/j.1467-7652.2008.00332.x
- Issue published online: 1 APR 2008
- Article first published online: 25 MAR 2008
- Received 2 October 2007; revised 19 February 2008; accepted 21 February 2008.
- glucose-6-phosphate/phosphate translocator (GPT);
- nucleotide translocator (NTT);
Transgenic potato (Solanum tuberosum) plants simultaneously over-expressing a pea (Pisum sativum) glucose-6-phosphate/phosphate translocator (GPT) and an Arabidopsis thaliana adenylate translocator (NTT1) in tubers were generated. Double transformants exhibited an enhanced tuber yield of up to 19%, concomitant with an additional increased starch content of up to 28%, compared with control plants. The total starch content produced in tubers per plant was calculated to be increased by up to 44% in double transformants relative to the wild-type. Single over-expression of either gene had no effect on tuber starch content or tuber yield, suggesting that starch formation within amyloplasts is co-limited by the import of energy and the supply of carbon skeletons. As total adenosine diphosphate-glucose pyrophosphorylase and starch synthase activities remained unchanged in double transformants relative to the wild-type, they cannot account for the increased starch content found in tubers of double transformants. Rather, an optimized supply of amyloplasts with adenosine triphosphate and glucose-6-phosphate seems to favour increased starch synthesis, resulting in plants with increased starch content and yield of tubers.