Acclimation of photosynthesis as a route in to improving crop yields
Project available for individuals with self arranged funding.
When plants are exposed to changes in their environment, they are able, to a greater or lesser extent, to alter the composition of their photosynthetic apparatus to match the environment in which they are growing – a process called dynamic acclimation. Recently, we identified a novel transporter that is essential to sensing or signalling this process. GPT2 is a glucose-6-phosphate/phosphate translocator found in the chloroplast envelope, and its expression is essential for plants to respond to changes in their environment, including increasing light and decreasing temperature. Examination of plants lacking GPT2 has shown that this pathway plays a major role in determining the productivity of plants in naturally variable environments.
This project offers the opportunity to a suitably qualified and committed student to contribute to our understanding of the process of GPT2-dependent acclimation and in particular to identifying novel additional steps in the acclimation process. Combining physiological measurments of photosynthesis with systems biology approaches, including the potential to examine changes in the transcriptome, proteome, and metabolome of plants exposed to variation in conditions, you will work to unravel the signalling pathways required for plants to acclimate. Plants growing under controlled conditions will be compared with plants under semi-natural greenhouse or fully natural conditions.
Analyses of various crop plants suggest that many of these are poorly acclimated to their environment. A better understanding of acclimation in plants would allow us to develop strategies to improve acclimation, increasing nitrogen use efficiency and stress tolerance, leading to higher yields.
-
Adaptive Organismal Biology
-
Biochemistry
-
Biotechnology
-
Cell Biology
-
Channels & Transporters
-
Environmental Biology
-
Gene Expression
-
Organelle Function
-
Plant Sciences
Fee Band
This project has a Band 2 fee.
Details of different fee bands are available for UK/EU or International applicants.
See: Fees.
|
Investigating the drought response of Arabidopsis with down-regulated programmed cell death.
Project available for individuals with self arranged funding.
Drought is the most severe adverse environmental factor limiting plant productivity in both natural and agricultural systems and climate change is expected to exacerbate this problem. Studies have shown that severe water deficit or prolonged drought induce premature root death. Drought-induced root death has been found in various crops and forest trees (Goss and Watson, 2003). Drought-induced root death is thought to be an active response of the plants to drought, allowing them to redirect root growth to reduce the effect of drought. It is therefore important to understand this adaptative response to drought to take it into account in crop breeding and biotechnology programmes. Recent evidence suggests that root cell death under water stress corresponds to an activation of programmed cell death (PCD). The Gallois lab has identified novel genes regulating PCD in plants, e.g Blanvillain et al 2011, He et al. 2008. The Johnson lab has expertise in the physiology and quantification of drought stress at the whole plant level (Hald et al. 2008). The student objectives will be: refine a drought model using Arabidopsis, use cell biology techniques to follow and quantify drought-induced root PCD, use mutant genetics to identify genes that modulate drought-induced root death, measure various whole plant parameters in including photosynthesis efficiency.
-
Blanvillain R., Young B., Cai Y.M., Hecht V., Varoquaux F., Delorme V., Lancelin JM, Delseny M. and Gallois P. (2011) The Arabidopsis peptide KISS OF DEATH is an inducer of Programmed Cell Death. The EMBO J., 30, 1173-1183.
-
Goss MJ, Watson CA. (2003). Both drought and excess water can induce premature root death, as can the resupply of water after drought. Journal of Crop Production 8:127-155.
-
Hald S, Nandha B, Gallois P, Johnson GN, (2008) Feedback regulation of photosynthetic electron transport by NADP(H) redox poise. Biochimica et Biophysica Acta. 1777(5):433-40.
-
He R, Drury GE, Rotari VI, Gordon A, Willer M, Farzaneh T, Woltering EJ, Gallois P, (2008) Metacaspase-8 modulates programmed cell death induced by ultraviolet light and H2O2 in Arabidopsis. The Journal of Biological Chemistry 283(2): 774-83.
-
Biotechnology
-
Environmental Biology
-
Molecular Biology
-
Plant Sciences
Fee Band
This project has a Band 2 fee.
Details of different fee bands are available for UK/EU or International applicants.
See: Fees.
|
Regulation of photosynthetic electron transport as a route to enhanced plant stress tolerance
Project available for individuals with self arranged funding.
The process of photosynthesis is the most important in nature and also the most vulnerable. Changing weather conditions, including periods of drought and high and low temperature, impact on the photosynthetic apparatus, resulting in the production of reactive oxygen species, (ROS) which can damage proteins, membranes and DNA.
Over a number of years, we have been examining the regulatory process that, in stress tolerant plants, can prevent damaging reactions. In particular, we have shown a major role of cyclic electron flow (CEF) and regulation of the cytochrome b6f complex in regulating electron flow to prevent ROS production. Work to date suggests that regulation of photosynthetic electron transport has the potential for improvement in crop plants, increasing stress tolerance and productivity. This project offers the opportunity to contribute to this aim.
You will use a combination of ultra-sensitive time-resolved spectroscopic approaches and biochemical analyses to examine how electron transport operates in intact leaves. The availability of a range of different mutants, in particular in the plant Arabidopsis thaliana, means that we can examine the role of individual proteins in regulation. Arabidopsis is readily transformed, meaning that it is possible to generate plants with different levels of proteins of interest, to establish the extent to which altering their expression might enhance regulation. You will join a thriving international lab, working alongside post-docs and PhD students working on closely related problems in plant biology.
-
Joliot P. and Johnson G.N. (2011) Regulation of Cyclic and Linear Electron Flow in Higher Plants. Proc. Nat. Acad. Sci 108, 13317-13322.
-
Johnson G.N. (2011) Physiology of PSI cyclic electron transport in higher plants. Biochim. Biophys. Acta - Bioenergetics 1807, 384-389.
-
Stepien P, Johnson GN. (2009). Contrasting responses of photosynthesis to salt stress in the glycophyte Arabidopsis thaliana and the halophyte Thellungiella halophila. Role of the plastid terminal oxidase as an alternative electron sink. Plant Physiology, 149, 1154-1165.
-
Hald S., Nandha B., Gallois P. and Johnson G.N. (2008) Feedback regulation of photosynthetic electron transport by NADP(H) redox poise. Biochimica et Biophysica Acta 1777 433-440
-
Nandha B., Finazzi G., Joliot P., Hald S. and Johnson G.N. (2007) The role of PGR5 in the redox poising of photosynthetic electron transport. Biochimica et Biophysica Acta 1767, 1252-1259
-
Adaptive Organismal Biology
-
Biochemistry
-
Biotechnology
-
Organelle Function
-
Plant Sciences
Fee Band
This project has a Band 2 fee.
Details of different fee bands are available for UK/EU or International applicants.
See: Fees.
|