O'Hara, LE;
(2014)
The role of trehalose 6-phosphate in the regulation of plant development and stress response.
Doctoral thesis , UCL (University College London).
Abstract
Prevailing environmental conditions impose limitations on the availability nutrients and photosynthetic rate of plants. Therefore, plants possess an array of mechanisms to sense and signal endogenous energy and nutrient availability in order to coordinate growth and development appropriately. Trehalose 6-phosphate (T6P) has emerged as an important molecule with a role in signalling carbon availability for the regulation of plant growth and development. This thesis aimed to investigate the extent to which T6P contributes to the regulation of growth over the course of plant development, and also during environmental stress. Plants expressing bacterial trehalose 6-phosphophate synthase (TPS) or trehalose 6-phosphate phosphatase enzymes were used to investigate the effects of increased or decreased T6P contents on growth and development, respectively. It was shown that T6P is required for the normal growth rate and the response to increased carbon availability in early development. Additionally, evidence is provided to implicate T6P in a further role in the crosstalk between sucrose and light- and auxin-mediated growth. T6P was found to be necessary for the acceleration of senescence in response to increased carbon availability and it was shown that sugar signals were sensed during early development. The importance of carbon availability during and after cold stress was demonstrated: sucrose alleviated the damage to the photosynthetic apparatus in mutants of starch synthesis and cold acclimation. It was also shown that T6P, via its effect on sucrose non-fermenting-1-related kinase-1 (SnRK1), is important in the growth recovery following cold stress which provokes sink limitation. A construct was created for the seed-specific over-expression of TPS behind the OLEOSIN1 promoter to alter levels of T6P in developing seeds. This approach may offer an effective method for improving seed yield and quality.
| Type: | Thesis (Doctoral) |
|---|---|
| Title: | The role of trehalose 6-phosphate in the regulation of plant development and stress response |
| Language: | English |
| UCL classification: | UCL > Provost and Vice Provost Offices UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences |
| URI: | https://discovery.ucl.ac.uk/id/eprint/1427275 |
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