Transgenic tobacco plants with improved cyanobacterial Rubisco expression but no extra assembly factors grow at near wild-type rates if provided with elevated CO2

A - Papers appearing in refereed journals

Occhialini, A., Lin, M. T., Andralojc, P. J., Hanson, M. R. and Parry, M. A. J. 2016. Transgenic tobacco plants with improved cyanobacterial Rubisco expression but no extra assembly factors grow at near wild-type rates if provided with elevated CO2. The Plant Journal. 85 (1), pp. 148-160.

AuthorsOcchialini, A., Lin, M. T., Andralojc, P. J., Hanson, M. R. and Parry, M. A. J.
Abstract

Introducing a carbon-concentrating mechanism and a faster Rubisco enzyme from cyanobacteria into higher plant chloroplasts may improve photosynthetic performance by increasing the rate of CO2 fixation while decreasing losses caused by photorespiration. We previously demonstrated that tobacco plants grow photoautotrophically using Rubisco from Synechococcus elongatus, although the plants exhibited considerably slower growth than wild-type and required supplementary CO2. Because of concerns that vascular plant assembly factors may not be adequate for assembly of a cyanobacterial Rubisco, prior transgenic plants included the cyanobacterial chaperone RbcX or the carboxysomal protein CcmM35. Here we show that neither RbcX nor CcmM35 is needed for assembly of active cyanobacterial Rubisco. Furthermore, by altering the gene regulatory sequences on the Rubisco transgenes, cyanobacterial Rubisco expression was enhanced and the transgenic plants grew at near wild-type growth rates, although still requiring elevated CO2. We performed detailed kinetic characterization of the enzymes produced with and without the RbcX and CcmM35 cyanobacterial proteins. These transgenic plants exhibit photosynthetic characteristics that confirm the predicted benefits of introduction of non-native forms of Rubisco with higher carboxylation rate constants in vascular plants and the potential nitrogen-use efficiency that may be achieved provided that adequate CO2 is available near the enzyme.

KeywordsPlant Sciences
Year of Publication2016
JournalThe Plant Journal
Journal citation85 (1), pp. 148-160
Digital Object Identifier (DOI)doi:10.1111/tpj.13098
PubMed ID26662726
Open accessPublished as bronze (free) open access
FunderBiotechnology and Biological Sciences Research Council
National Science Foundation - US
National Institute of General Medical Sciences of the National Institutes of Health (USA)
Cornell University Biotechnology Resource Center (National Institutes of Health)
Funder project or codeWheat
Project: 5138
[20:20 Wheat] Maximising yield potential of wheat
ISSN09607412
0960-7412
PublisherWiley
Grant IDS10RR025502
F32GM103019
EF-1105584
BB/I024488/1

Permalink - https://repository.rothamsted.ac.uk/item/8v16w/transgenic-tobacco-plants-with-improved-cyanobacterial-rubisco-expression-but-no-extra-assembly-factors-grow-at-near-wild-type-rates-if-provided-with-elevated-co2

16 total views
0 total downloads
1 views this month
0 downloads this month