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The reproductive characteristics of a wide range of freshwater-resident and anadromous Scottish forms of Salmo trutta were examined. A total of 653 females were sampled from 27 wild and two long-term domestic populations covering a fork length range of 116-725mm. Total fecundities of the wild fish were 51-5952 eggs. Egg diameters ranged from 3.6 to 6.4mm. Gonadosomatic indices ranged from 5-26%. The youngest females were 2+ years. Trout from fast-growing populations matured earlier and were shorter-lived than slow-growing trout. Regression equations for the relationship between body size and fecundity and egg diameter are provided for the national data set and for individual and grouped populations. Significant differences in fecundity and egg diameter were found between populations. After standardisation to a common body length, fecundity and GSI were found to be positively and egg diameter negatively correlated with trophic status of the water bodies and with early growth rate. The domestic populations provided the overall highest relative fecundities and smallest egg diameters. Fecundity of wild trout was negatively and egg diameter positively correlated with latitude. There was no relationship with numbers of other fish species present. Above-falls trout were short-lived, yet had high relative fecundity and small egg size. In these populations, age was more important than length in determining egg diameter. The rate at which maturity is reached, varying between populations, may be more important than absolute growth rate in determining fecundity and egg size. Lifetime eggs per female and instantaneous production by 1000 females were estimated for individual populations. The significance of the estimates for the River Ewe System in north west Scotland, an area of recent sea trout population decline, is discussed.

In flowering plants, successful pollination is important for sexual reproduction. It involves a series of intercellular communication pathways between male and female tissues. This cell-cell communication includes the attraction and reception of the male gametophyte, or pollen tube (PT), by the synergid cells of the female gametophyte, also known as the embryo sac (ES). To achieve reproductive success, it is important to manipulate reproduction at both quality and quantity levels. In other words, flowering plants can only produce as many seeds as they produce ovules and these ovules must be able to be fertilized to make seeds. In <i>Arabidopsis thaliana</i>, <i>NORTIA (NTA)</i>, a member of the MILDEW RESISTANCE LOCUS O (MLO) family of proteins, plays a critical role in the communication process that regulates PT reception. Upon PT arrival at the filiform apparatus, <i>NTA</i>becomes polarly redistributed from the Golgi-associated compartment to the filiform apparatus of the synergid cell, indicating that PT-triggered regulation of the synergid secretory system is important for synergid function during pollination. In the first part of this dissertation, I will describe my research of the female controlled reproductive success at molecular and cell biology level with a focus on <i>NTA</i>. Moreover, the ovules contain the female gametophytes which are fertilized during pollination to initiate seed development. Thus, ovule development is an essential and crucial process during plant growth. More importantly, the number of ovules will limit the quantity of reproductive success. However, the major regulators are still poorly understood. The remaining chapters of my dissertation describethe identification of key components that affect the number of ovules during plant development by using natural variation in <i>Arabidopsis thaliana </i>and the correlations of ovule number with flowering time. Discovering new ovule number regulators could provide new tools for improving the agricultural productivity.<br>

Le changement climatique et l’augmentation des températures globales perturbent l’abondance et la distribution de milliers d’organismes, aquatiques et terrestres, et certains écosystèmes sont particulièrement sensibles à ces changements environnementaux. L’augmentation de température est la principale menace au maintien des populations de coraux, véritables ingénieurs écologiques de ces écosystèmes. Bien que la recherche sur les récifs coralliens se soit d’abord attachée à l’étude des coraux adultes, de nombreuses informations manquent sur la reproduction sexuée et asexuée, et leur rôle dans la conservation et restauration récifale. Le premier axe de ma thèse s’est donc construit sur la réponse des jeunes stades de vie à l’augmentation de température, pour d’abord évaluer les modifications de leur performance et ensuite évaluer dans quelles mesures les jeunes stades seraient capables de s’acclimater à des conditions de températures plus élevées. Au travers de différentes expérimentations en laboratoire sur le genre Acropora, j’ai ainsi mis en évidence 1) une résistance thermique importante (+2-3°C au-dessus des températures ambiantes) des gamètes face à l’augmentation de température, 2) une résistance thermique différente entre spermatozoïdes et ovocytes: ovocytes < spermatozoïdes, 3) et la mise en évidence du rôle majeur de l’environnement dans lequel se rencontre les gamètes une fois libérés, sur la qualité et la quantité de la fécondation. Enfin, j’ai identifié les conditions optimales thermiques de pré-exposition des gamètes pour maximiser leur succès de fécondation. Bien qu’un intérêt croissant soit porté sur la reproduction sexuée ces dernières années, l’utilisation de la reproduction asexuée demeure la méthode la plus utilisée pour restaurer les récifs coralliens, plus connue sous le nom de bouturage. Ainsi le second axe de ma thèse a cherché à mettre en évidence la plasticité phénotypique des coraux en cultivant des boutures provenant de 3 espèces dans 3 environnements différents et en analysant leur taux de croissance, leur état de santé et leur survie. Cet axe a pu montrer qu’il existait des différences à plusieurs échelles, entre espèces, mais aussi au sein d’une même espèce. Mes travaux montrent qu’une sélection des individus basée sur l’étude de la plasticité phénotypique de certains traits d’histoires de vie comme la croissance ou l’état de santé dans des environnements variables permettrait d’améliorer l’efficacité de la restauration récifale. Ainsi le choix des individus au sein d’une même espèce afin de réaliser du bouturage (reproduction asexuée) et le conditionnement de la phase de vie gamètes (reproduction sexuée) peut permettre d’augmenter l’efficacité des méthodes de restaurations tout en nous donnant des informations nouvelles sur la biologie et la physiologie des coraux scléractiniaires face aux changements environnementaux. / Climate change and increasing temperature impact abundance and distribution of thousands of organisms, aquatic and terrestrial, and some ecosystems are particularly sensitive to these global changes. Increasing temperature is the principal threat for coral populations, which are ecological engineers of coral reef ecosystems. While research on coral reefs has first sought to study adult corals, data are still lacking on early life stages of corals. As sexual and asexual reproduction may play a key role in the conservation and restoration of coral reefs, my doctoral research aims to better understand changes on sexual and asexual reproduction in the face of rising temperature. The first axis of my Ph. D. was built on the response of early life stages to increasing temperature, in order to assess whether pre-exposure of early life may improve their ulterior performance. Among the different experiments performed on the genus Acropora, I highlighted 1) a high thermal tolerance (+2-3°C above ambient temperature) of gametes, 2) a higher sensibility of oocytes than sperm to rising temperature exposure, and 3) the pivotal role of gamete thermal history on fertilization output. Finally, I identified optimal pre-exposure conditions in order to maximize fertilization success. While an increasing interest in sexual reproduction was observed these last years, asexual reproduction and fragmentation still remain the main tool to restore damaged reefs. Thus, in the second axis of my doctoral project, I investigated the phenotypic plasticity of corals by growing 3 different species of corals across 3 different environments. Their growth rates, health status and survival probability were determined. Results from this axis showed that differences were observed at the interspecific and intraspecific levels. This work revealed that a selection based on phenotypic plasticity among different life-traits (growth rates and health status) and different environments should allow to increase coral reef restoration strategies. Hence the selection of individuals (asexual reproduction) in a species based on coral common garden experiment allow to identify individuals of interest to use as restoration biological materials. Additionally, thermal pre-conditioning of early life stages (sexual reproduction) is another way to increase efficiency of restoration measures in the face of rising temperature. My doctoral research provided new information regarding physiological and biological processes of scleractinian corals facing environmental changes and proposed new solutions for restorations based on sexual and/or asexual reproduction.

Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-02

Lo Ting Sze. / Thesis submitted in: December 2002. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 145-170). / Abstracts in English and Chinese. / Declaration --- p.i / Abstract --- p.ii / Acknowledgements --- p.vii / List of Contents / Contents in Brief --- p.viii / Contents in Detail --- p.ix / List of Figures and Tables / List of Figures --- p.xiii / List of Tables --- p.xvi / Chapter Chapter 1 --- Introduction and literature review General introduction --- p.1 / Chapter 1.1 --- Structural changes in ovary of penaeid shrimp during maturation --- p.3 / Chapter 1.2 --- Biochemical and physiological changes in ovary of penaeid shrimp during maturation --- p.7 / Chapter 1.2.1 --- Variation of protein content --- p.7 / Chapter 1.2.1.1 --- Changes of proteins in ovary of penaeid shrimp during maturation --- p.7 / Chapter 1.2.1.2 --- Biochemical characterization of vitellin --- p.8 / Chapter 1.2.1.3 --- Site of vitellogenin synthesis --- p.10 / Chapter 1.2.2 --- Variation of lipid composition --- p.12 / Chapter 1.2.2.1 --- Role of lipids in ovary of penaeid shrimp --- p.12 / Chapter 1.2.2.2 --- Changes of lipids in ovary of penaeid shrimp during maturation --- p.13 / Chapter 1.2.3 --- Variation of other nutrient contents --- p.16 / Chapter 1.3 --- Endocrine control of ovarian maturation in penaeid shrimp --- p.16 / Chapter 1.3.1 --- Gonad-inhibiting hormone (GIH) --- p.17 / Chapter 1.3.2 --- Crustacean hyperglycemic hormone (CHH) --- p.19 / Chapter 1.3.3 --- X-organ sinus gland complex (XOSG) and CHH neuropeptide family --- p.20 / Chapter 1.3.4 --- Gonad-stimulating hormone (GSH) --- p.22 / Chapter 1.3.5 --- Methyl farnesoate (MF) --- p.23 / Chapter 1.3.6 --- Neurotransmitters --- p.24 / Chapter 1.3.7 --- Other factors --- p.26 / Chapter 1.3.8 --- Androgenic hormone (AH) --- p.27 / Chapter 1.4 --- Ecology and reproductive biology of Metapenaeus ensis --- p.29 / Chapter 1.4.1 --- Identification --- p.29 / Chapter 1.4.2 --- Ecology --- p.29 / Chapter 1.4.3 --- Reproductive biology --- p.30 / Chapter 1.5 --- Objective of research --- p.32 / Chapter Chapter 2 --- "Variation of circulating gonad-inhibiting hormone (GIH) level during ovarian maturation in the shrimp, Metapenaeus ensis" / Chapter 2.1 --- Introduction --- p.34 / Chapter 2.2 --- Materials and methods --- p.35 / Chapter 2.2.1 --- Experimental animals and serum extraction --- p.35 / Chapter 2.2.2 --- Protein content assay --- p.36 / Chapter 2.2.3 --- SDS-polyacrymide gel electrophoresis (SDS-PAGE) --- p.39 / Chapter 2.2.4 --- Western blot --- p.40 / Chapter 2.2.5 --- Purification of IgG from antiserum --- p.42 / Chapter 2.2.6 --- ELISA assay (indirect ELISA) --- p.42 / Chapter 2.3 --- Results --- p.44 / Chapter 2.3.1 --- Experimental animals --- p.44 / Chapter 2.3.2 --- Purification of anti-GIH IgG --- p.46 / Chapter 2.3.3 --- Optimization of indirect ELISA --- p.46 / Chapter 2.3.4 --- Determination of circulating GIH in haemolymph --- p.51 / Chapter 2.4 --- Discussion --- p.55 / Chapter Chapter 3 --- "Identification of genes differentially expressed during ovarian maturation in the shrimp, Metapenaeus ensis" / Chapter 3.1 --- Introduction --- p.60 / Chapter 3.2 --- Materials and methods --- p.61 / Chapter 3.2.1 --- Outline of methodology --- p.61 / Chapter 3.2.2 --- Experimental animals --- p.62 / Chapter 3.2.3 --- Total RNA extraction --- p.62 / Chapter 3.2.4 --- RNA arbitrarily primed PCR (RAP-PCR) --- p.64 / Chapter 3.2.5 --- DNA electrophoresis by agarose gel --- p.68 / Chapter 3.2.6 --- DNA electrophoresis by polyacrylamide gel --- p.68 / Chapter 3.2.7 --- Preparation of DIG-labeled probe from PCR product --- p.69 / Chapter 3.2.8 --- Checking for DIG-labeling yield --- p.69 / Chapter 3.2.9 --- Excision of cDNA library from ovary of Metapenaeus ensis --- p.70 / Chapter 3.2.10 --- PCR screening of insertion sequence --- p.73 / Chapter 3.2.11 --- Dot-blot --- p.75 / Chapter 3.2.12 --- Dot-blot hybridization --- p.76 / Chapter 3.2.13 --- Growth of cell for plasmid preparation --- p.79 / Chapter 3.2.14 --- Permanent culture preparation --- p.80 / Chapter 3.2.15 --- DNA Sequencing --- p.80 / Chapter 3.2.16 --- RNA formaldehyde denaturing gel electrophoresis --- p.82 / Chapter 3.2.17 --- Northern blot --- p.84 / Chapter 3.2.18 --- Northern hybridization --- p.84 / Chapter 3.2.19 --- 5´ة RACE (rapid amplification of cDNA ends) --- p.88 / Chapter 3.3 --- Results --- p.92 / Chapter 3.3.1 --- Experimental animals --- p.92 / Chapter 3.3.2 --- Total RNA extraction --- p.92 / Chapter 3.3.3 --- RNA arbitrarily primed PCR (RAP-PCR) --- p.92 / Chapter 3.3.4 --- Titer of cDNA library from Metapenaeus ensis ovary --- p.95 / Chapter 3.3.5 --- PCR screening of insertion sequence --- p.95 / Chapter 3.3.6 --- Dot-blot hybridization --- p.99 / Chapter 3.3.7 --- DNA sequencing of differentially expressed genes --- p.96 / Chapter 3.3.8 --- Northern analysis --- p.99 / Chapter 3.3.8.1 --- Housekeeping gene - elongation factor 1α --- p.106 / Chapter 3.3.8.2 --- Translationally controlled tumor protein (TCTP) --- p.106 / Chapter 3.3.8.3 --- Cytoskeletal actin --- p.109 / Chapter 3.3.8.4 --- Keratin --- p.109 / Chapter 3.3.8.5 --- Heat shock cognate 70 kD protein (hsc70) --- p.109 / Chapter 3.3.8.6 --- Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) --- p.117 / Chapter 3.3.8.7 --- Arginine kinase --- p.117 / Chapter 3.3.8.8 --- High mobility group 1-like protein (HMGl-like protein) --- p.122 / Chapter 3.3.8.9 --- Nucleoside diphosphate kinase --- p.122 / Chapter 3.4 --- Discussion --- p.122 / Chapter 3.4.1 --- RAP-PCR and dot-blot hybridization --- p.122 / Chapter 3.4.2 --- Functions of differentially expressed genes in ovarian maturation --- p.128 / Chapter 3.4.2.1 --- Translationally controlled tumor protein (TCTP) --- p.128 / Chapter 3.4.2.2 --- Cytoskeletal actin --- p.130 / Chapter 3.4.2.3 --- Keratin --- p.130 / Chapter 3.4.2.4 --- Heat shock cognate 70 kD protein (hsc70) --- p.131 / Chapter 3.4.2.5 --- Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) --- p.134 / Chapter 3.4.2.6 --- Arginine kinase --- p.135 / Chapter 3.4.2.7 --- High mobility group 1-like protein (HMGl-like protein) --- p.136 / Chapter 3.4.2.8 --- Nucleoside diphosphate kinase --- p.137 / Chapter 3.4.3 --- Speculation on the molecular changes in ooctyes during ovarian maturation --- p.139 / Chapter Chapter 4 --- General conclusion --- p.142 / References --- p.145