Acclimation of photosynthesis allows plants to adjust the composition of their photosynthetic apparatus to adapt to changes in the environment, and is important in maintaining fitness. Dynamic acclimation refers to acclimation of fully developed leaves, after developmental processes have ceased. Rates of photosynthesis fluctuate with environmental change, and this requires metabolic adjustments. It has previously been shown that acclimation requires the chloroplastic glucose 6-phosphate/ phosphate translocator GPT2. Using label-free proteomics we characterised the acclimation deficient gpt2 mutant. High light acclimation involves changes in the composition of the photosynthetic proteome and increases in many other metabolic enzymes, but in gpt2 plants, a reduced ability to alter protein composition, and enhanced stress responses were seen. Using a combined transcriptomics and proteomics approach we also analysed acclimation to low temperature. We show that photosynthetic acclimation requires the cytosolic fumarase, FUM2. In fum2 mutants, an enhanced transcriptional response to low temperature was seen, which was impaired at the level of the proteome, relative to the WT. We also identified a protein encoding a β-Amylase, BAM5, that strongly responded to high light acclimation. The role of this protein was further characterised, and we show a nonchloroplastic location. Furthermore, suppression of this gene resulted in plants that were unable to acclimate, and had a reduced sugar content. This research highlights novel and diverse roles for proteins in acclimation, and provides a comprehensive proteomic profiling of high light and low temperature acclimation that has previously been lacking.

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Growth rate and flowering time are agriculturally important traits that are linked to fitness, productivity and reproductive success of plants. To study the genetic basis for natural variation in growth rate and flowering time between local accessions of Arabidopsis thaliana, hybrids were produced between fast growing / late flowering and slow growing / early flowering parents. F3 and F5 hybrid families were grown under a range of conditions – under a constant controlled environment, outside over the winter and outside in spring and early summer. Growth rates were estimated from repeated images of rosettes. Flowering time, as number of leaves to flower, was also recorded both in control and natural conditions for F5 lines. Damage by slugs and stress-induced production of anthocyanin pigments were also recorded for plants grown outside. Broad-sense heritability estimates were higher for F5 families than F3, in which more loci will segregate, and ranged from 48% to 89%. No significant correlation between growth rates under different environments was observed in most cases for F3 populations, however significant correlations were detected for F5 families outside and under controlled conditions, suggesting that same genes can affect growth rate in more than one environment. The genotypes of F3 families were determined at thirty-nine SSLP (simple sequence length polymorphism) loci and used in regression with phenotype data to search for quantitative trait loci (QTL). Significant QTLs were detected in F3 families for growth rate, flowering time and anthocyanin production, but not for herbivore damage. To confirm QTL detected in the F3 and to detect additional loci, bulk segregant analysis was carried out in F5 families grown under different conditions. Potentially linked markers were tested further in individual F5 plants and QTL mapped on a finer scale in F5 families that remained heterozygous for candidate regions. VIP5 and LDL1 were selected as potential candidate genes for flowering time variation. These genes were sequenced for two parental alleles. A transposon insertion and 5’ UTR deletion were found in the LDL1 allele from the late flowering parent and SNPs (single nucleotide polymorphisms) were observed throughout the gene. However both alleles appeared to be expressed at similar levels. Transgenic lines have been produced carrying the LDL1 allele from the early flowering parent (4D1) in the background of the later flowering parent (11C1). This work is on-going and will hopefully reveal whether LDL1 underlies differences in flowering behaviour seen between 11C1 and 4D1.

Increases in temperature damage plant cells, and plants react to heat stress by inducing of a number of protective mechanisms. In this study, it has been shown that heat damages cells both directly while the plants are being heated, and indirectly through heat induced oxidative stress during recovery from heating. Different stress response pathways are induced in each case. Evidence implicates salicylic acid, abscisic acid, ACC (a precursor of ethylene), calcium ions and active oxygen species in pathways resulting in thermotolerance (i.e. increased survival at high temperature). Addition of these potential second messengers results in increased survival and decreased oxidative damage after heating (as measured using the TBARS assay), while silencing the pathways through use of mutants, inhibitors or transgenes results in decreased thermotolerance. In vivo calcium measurements show cytosolic calcium transients only at initiation of cooling after heat stress. Calcium chloride also induces thermotolerance when added after heating, as does ACC. These substances can induce early increases in ascorbate peroxidase activity after heating, and induce expression of antioxidant genes. Thus they may play a role in heat induced oxidative stress response pathways in recovery. Two different pathways induced during heating appear to result in the expression of genes for heat shock proteins. The predominant pathway induced at 30oC involves ABA, while that at 35-40oC involves an oxidative burst generated through the NADPH oxidase, atrbohB. Addition of SA can induce HSP (heat shock protein) expression, but there is little evidence that this occurs endogenously in plant cells, although nahG plants unable to signal via SA are thermosensitive. Results in this study indicate that there are several signalling pathways associated with heat shock. The pathway induced during recovery from heating involves calcium ions and ethylene, and results in increased antioxidant capacity. During heating two pathways induce expression of HSPs: one involving abscisic acid and possibly salicylic acid and one involving an oxidative burst. At least one further pathway is believed to exist, which involves protein kinases and phosphatases as heat shock causes up-regulation of expression of certain genes for these signalling components.

Rab GTPases are major regulatory proteins of vesicle traffic and thus responsible for membrane identity, vesicle targeting and vesicle fusion. The angiosperm Rab GTPase family is grouped into eight clades (Rab-A to Rab-H) that are broadly conserved in animals and yeasts. It has been proposed that the Rab-A clade has diversified in land plants giving rise to six plant- specific structural subclasses, Rab-A1 to Rab-A6. Previous work suggests that the Arabidopsis Rab-A2 and Rab-A3 proteins define a novel endosomal compartment that lies on a pathway between the Golgi and the plasma membrane. In dividing cells, the Rab-A2/A3 compartment is implicated in biosynthetic traffic to the cell plate but it is unclear what traffics through this compartment in non-dividing cells. In this project, I investigated a range of membrane trafficking pathways in Arabidopsis thaliana. These were probed for dependency on RAB-A2a function, using the dominant negative approach combined with fluorescent marker technology. The data presented in this thesis suggests that RAB-A2a acts on a protein recycling pathway that is used by PIN2:GFP.

Angiosperm seed development requires co-ordinated development of the embryo and a second zygotic tissue, the endosperm. In Arabidopsis thaliana, the endosperm is ephemeral and is largely consumed by the embryo during seed development. In addition to a role in embryo nutrition, it is also likely that the endosperm may play a more direct role in signalling to the embryo to regulate development. Despite their importance for embryo development, these processes are very poorly understood. The ZHOUPI (ZOU) gene provides an important tool to address these problems. Firstly, ZOU likely regulates endosperm breakdown. Whereas wild-type seed have a single layer of endosperm at maturity, zou seed has a large persistent endosperm and a correspondingly small embryo. The small zou embryo does not fill the seed so that the seed shrivels as it desiccates during maturation. Secondly, zou embryos have defects in their cuticle, so that the endosperm adheres to the embryo throughout seed development. After seed germination, zou cotyledons develop holes in their epidermis as they expand, probably due to the defects in the cuticle. ZHOUPI (ZOU) encodes a bHLH transcription factor and is expressed in the embryo surrounding region (ESR) of endosperm but not in the embryo itself. The role of ZOU in cuticle development is partly mediated by the ABNORMAL LEAF SHAPE1 (ALE1) gene. Thus, ale1 mutants also show defects in embryonic cuticle development and ALE1 is specifically expressed in ESR in a ZOU-dependent fashion. It was unclear whether the effects of ZOU upon embryo development are an indirect consequence of the persistent endosperm mechanically impeding embryo expansion, or rather reflect a more direct role of the ESR in signalling to the embryo. The main aims of this thesis were 1) to provide evidence that ZOU regulates endosperm cell death and 2) to test whether ZOU function in controlling endosperm cell death could be separated from that in embryonic epidermal cuticle development. To achieve this goal, 1) TUNEL assays were performed in the seeds to confirm the zou endosperm cell death phenotype, 2) ALE1 expression in the ESR in zou mutants was rescued using the ZOU-independent AtSUC5 promoter to investigate whether one or both of zou phenotypes were complemented, 3) Candidate ZOU target genes were validated and characterized to determine their functions in endosperm cell death and/or embryonic epidermal cuticle development. The TUNEL assays revealed that zou mutants display less DNA fragmentation in the ESR than that of the wild-type, but that zou did not have defects in cell death outside the seeds suggesting ZOU specifically regulated endosperm cell death. The AtSUC5::ALE1 transgene partially rescued zou defects in epidermal cuticle but not in endosperm cell death. This shows that the defects in the zou cuticle are not caused by the defective endosperm, rather zou has distinct, separable functions. Lastly, I characterised several novel ZOU targets and showed that RGP3 may be a direct ZOU target as it is expressed in ESR in ZOU dependent fashion, whereas RGP4 is likely indirect as it is expressed in the testa and up-regulated in zou mutants. In conclusion, ZOU has independent roles in endosperm cell death and embryonic epidermal cuticle development. Because ALE1, which largely mediates the role in cuticle development, is less widely conserved than is ZOU, the role in promoting endosperm cell death may be the ancestral function of ZOU.

Partint de la lectura dels textos literaris espanyols dels segles XIII al XVI, aquest treball examina la concepció medieval del son i del somni. Es constata el fet que la cultura onírica pagana no va ser totalmen erradicada dels costums quotidians populars, tot i el discurs antisupersticiós de l'Esglèsia; a més, l'ascetisme va jugar un paper important en la apreciació del son i, en conseqüència, en la desconfiança envers els somnis; finalment, l'explotació literària que se'n féu de les percepcions oníriques creix en la mesura que el discurs onirològic de la medicina i la psicologia prevalen per sobre de la teologia.Són especialment sotmesos a examen en aquest estudi textos hagiogràfics (Vida de Santa María Magdalena), èpics (Poema de Fernán González), novel.les cavalleresques (Las Sergas de Esplandián, de Garci Rodríguez de Montalvo, Florisando, de Páez de Ribera, y Palmerín de Olivia) i dos textos moderns: La Lozana andaluza, de Francisco Delicado, i Las lágrimas de Angélica, de Luis Barahona de Soto. / El presente estudio examina en qué forma aparece reflejada la concepción medieval del sueño (entendido como la acción de dormir) y de los ensueños (representaciones oníricas) en la literatura española de los siglos XIII al XVI. Se llega a la constatación de que la cultura onírica pagana no fue absolutamente erradicada de las creencias populares y de sus usos cotidianos, a pesar del discurso antisupersticioso de la Iglesia; en segundo lugar, el ascetismo cristiano jugó un papel importante en la apreciación del sueño y, por consiguiente, en la desconfianza hacia las percepciones oníricas; por último, la explotación literaria de los sueños aumenta cuando en el discurso onirológico la medicina y la psicología priman sobre la teología.El libro atiende con especial detalle a textos hagiográficos (Vida de Santa María Magdalena), épicos (Poema de Fernán González), libros de caballerías (Las Sergas de Esplandián, de Garci Rodríguez de Montalvo, Florisando, de Páez de Ribera, y Palmerín de Olivia) y dos obras singulares del quinientos: La Lozana andaluza de Francisco Delicado y Las lágrimas de Angélica de Luis Barahona de Soto. / This dissertation is an inquiry into the nature of medieval conceptions of sleeping and dreaming and how are they reflected in the spanish literary texts between XIIIth and XVIth centuries. It concludes with three convictions: first, that the pagan culture concerning dream visions was not absolutly eradicated from daily popular customs, despite of ecclesiastical censures againts superstitions; secondly, that ascetic christian doctrine is relevant to understand medieval conceptions of sleeping and, consequently, of dreaming; and, finaly, that oneiric literary exploitation increase when medical and psichological theories of dream experiences prevail over theology.This study deals mainly with medieval hagiography (Vida de Santa María Magdalena), epic poetry (Poema de Fernán González), chivalric romance (Garci Rodríguez de Montalvo's Las Sergas de Esplandián, Páez de Ribera's Florisando, the anonymous Palmerín de Olivia) and two modern texts: La Lozana andaluza by Francisco Delicado, and Luis Barahona de Soto's Las lágrimas de Angélica..

The archaeological and technical questions about ancient stone tools lead to various research activities such as chemical and petrographical analysis. Considering research areas and publications it can be suggested that mineralogical studies of stone samples of ancient stone tools have disclosed useful information concerning identification of the stone. Within this context, aim of this study is to determine the chemical, mineralogical and petrographical identities of the stone samples of Karain Cave (Antalya). Most paleolithic caves show one specific time interval layer but Karain Cave shows lower-upper and middle layers which give information about the migration ways between Near East and Europe. Stone tools excavated from Karain Cave are not only first human remainings in Anatolia but also first artworks of Anatolian people.Most of the stone tools excavated from Karain Cave are cherts. These cherts were analysed for archeological aspects but mineralogical, petrographical, and chemical contents have not been analysed yet. During the excavations at the Karain Cave in Antalya many stone pieces in different sizes and colors had been found. In this study ten samples were examined. The methods used consists of thin section, X- ray powder diffraction , scanning - electron microscopy coupled with energy dispersive X-ray analysis , differential thermal analyses and inductively coupled plasma mass spectrometry to determine material characteristics of the samples. Petrographically the nine of the samples are chert with some including radiolarian fossils. Microcrystalline &aacute / - quartz is the major mineral in the chert. Only one sample is composed calcite and is identified as micritic limestone. Chemical analysis reflect the typical composition of chert with the average values of / 40.9% Si and 1 sample is limestone, which is composed of 35.7% Ca . Minor elements are Fe, Al, K, and Ti in the samples. Thermal analysis is also supported the thin section studies.Further research is suggested for provenance analysis of stone tools from the Karain Cave.

Acacia senegal and Acacia seyal are important agroforestry cash crops indigenous to several countries of sub-Saharan Africa, including Nigeria. The gum exudate produced by these species is termed gum Arabic which is an approved food additive (E414), primarily used as an emulsifier. In the current study, the molecular structure, composition and biophysical properties of gum samples harvested from mature trees of Acacia senegal at two specific ecolocations in Nigeria (NG1 and NG2), have been investigated together with two previously characterised gum samples harvested from A. senegal and A. seyal originating from Sudan. The monosaccharide sugar composition analyses have shown that the A. seyal gum had a lower rhamnose and glucuronic acid content than the A. senegal gum, but had higher arabinose content. No significant difference was observed between the sugar composition of the A. senegal gums from Sudan and Nigeria. The total protein content of the Nigerian gum samples were significantly higher than recorded for the Sudanese samples. The principal amino acids present in all the gum samples are hydroxyproline, serine, aspartame, threonine and proline which is in agreement with literature values. The hydrodynamic size of the molecules present in the gums was studied using dynamic light scattering and it was found that molecular association occurred in solution over time which was inhibited in the presence of an electrolyte. The comparison of droplet size distribution for emulsions prepared with A. senegal (NG1) and A. seyal gum samples showed that A. senegal sample was a better emulsifier than the A. seyal. Multilayer adsorption of the samples onto polystyrene latex particles was observed, which resulted in an increase in thickness of the adsorbed layer as a consequence of the interaction between the protein and carbohydrate within the molecules adsorbed on the emulsion surface. Preliminary analyses of the gums using transmission electron microscopy showed the presence of varied macromolecules, ranging in size from ~12 - ~60 nm. Immuno-gold negative staining (using JIM8 monoclonal antibody) indicated clear labelling of arabinogalactan-proteins present in the gums harvested from A. senegal, the labelling of the A. seyal sample was inconclusive. In summary, the data presented represents the first detailed comparison of the structure, composition and physicochemical characteristics of Nigerian Acacia gum exudates versus Sudanese samples (main global supplier) which have shown that gum obtained from Nigerian sources is a viable alternative to ensure future supply of this valuable natural resource.

<b>Cardamine hirsuta</b> L. is an emerging model system in developmental genetics, where natural genetic variation within <b>C. hirsuta</b> provides the means to investigate the genetic basis of morphological traits. This thesis investigates the geographical structure and genealogical history of genetic variation within <b>C. hirsuta</b> and identifies its closest relatives. This will enable the accurate selection of species for comparison with <b>C. hirsuta</b> when making interpretations of evolutionary processes, and provide a better understanding of morphological character evolution in <b>C. hirsuta</b>. The phylogeographic history of <b>C. hirsuta</b> was reconstructed using multiple chloroplast and nuclear markers and widespread accession sampling from across its native range. A distinct group was identified within <b>C. hirsuta</b>, restricted to the high mountains of East Africa. Climate suitability modelling showed that Pleistocene glacial dynamics have had a strong effect on the distribution of genetic variation within <b>C. hirsuta</b>. The phylogeographical data generated here was used to investigate the origin of <b>C. hirsuta</b> in the Azores, an oceanic archipelago. The Azores are dominated by an endemic chloroplast haplotype which is associated with an endemic phenotype. Thus, <b>C. hirsuta</b> appears to have diversified <b>in situ</b> in the Azores. Phylogenetic analyses of Cardamine, restricted to diploid species to remove the confounding effects of polyploids, found that <b>C. hirsuta</b> is most closely related to <b>C. oligosperma</b>, a western North American species. Multiple loci and extensive intraspecific sampling were brought to bear to demonstrate that <b>C. hirsuta</b> and <b>C. oligosperma</b> are reciprocally monophyletic. <b>Cardamine pattersonii</b>, a restricted endemic from north-west Oregon is likely to be an allopolyploid, with <b>C. oligosperma</b> as the maternal parent and possibly <b>C. nuttallii</b> as the paternal parent.