Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available in print.

published_or_final_version / abstract / Pathology / Master / Master of Philosophy

Thesis (Ph. D.)--Ohio State University, 2008.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

No description available.

Thesis (Ph. D.)--University of North Texas, May, 2009. / Title from title page display. Includes bibliographical references.

Cells contain an elaborate cytoskeleton which plays a major role in a variety of cellular functions including: maintenance of cell shape and dimension, providing mechanical strength, cell motility, cytokinesis during mitosis and meiosis and intracellular transport. The cell cytoskeleton is made up of three types of protein filaments: the microtubules, the intermediate filaments and the actin cytoskeleton. These components interact with each other to allow the cell to function correctly. When functioning incorrectly, disruptions to many cellular pathway have been observed with mutations in various cytoskeletal proteins causing an assortment of human disease phenotypes. Characterization of these filament systems in different cell types is essential to the understanding of basic cellular processes and disease causation. The studies in this thesis are concerned with examining specific cytoskeletal tropomyosin-defined actin filament systems in skeletal muscle. The diversity of the actin filament system relies, in part, on the family of actin binding proteins, the tropomyosins (Tms). There are in excess of forty Tm isoforms found in mammals which are derived from four genes: α, β, γ and δTm. The role of the musclespecific Tms in striated muscle is well understood, with sarcomeric Tm isoforms functioning as part of the thin filament where it regulates actin-myosin interactions and hence muscle contraction. However, relatively little known about the roles of the many cytoskeletal Tm isoforms. Cytoskeletal Tms have been shown to compartmentalise to form functionally distinct filaments in a range of cell types including neurons (Bryce et al., 2003), fibroblasts (Percival et al., 2000) and epithelial cells (Dalby-Payne et al., 2003). Recently it has been shown that cytoskeletal Tm, Tm5NM1 defines a cytoskeletal structure in skeletal muscle called the Z-line associated cytoskeleton (Z-LAC) (Kee et al., 2004).The disruption of this structure by over-expression of an exogenous Tm in transgenic mice results in a muscular dystrophy phenotype, indicating that the Z-LAC plays an important role in maintenance of muscle structure (Kee et al., 2004). In this study, specific cytoskeletal Tms are further investigated in the context of skeletal muscle. Here, we examine the expression, localisation and potential function of cytoskeletal Tm isoforms, focussing on Tm4 (derived from the δ- gene) and Tm5NM1 (derived from the γ-gene). By western blotting and immuno-staining mouse skeletal muscle, we show that cytoskeletal Tms are expressed in a range of muscles and define separate populations of filaments. These filaments are found in association with a number of muscle structures including the myotendinous junction, neuromuscular junction, the sarcolemma, the t-tubules and the sarcoplasmic reticulum. Of particular interest, Tm4 and Tm5NM1 define cytoskeletal elements in association with the saroplasmic reticulum and T-tubules, respectively, with a separation of less than 90 nm between distinct filamentous populations. The segregation of Tm isoforms indicates a role for Tms in the specification of actin filament function at these cellular regions. Examination of muscle during development, regeneration and disease revealed that Tm4 defines a novel cytoskeletal filament system that is orientated perpendicular to the sarcomeric apparatus. Tm4 is up-regulated in both muscular dystrophy and nemaline myopathy and also during induced regeneration and focal repair in mouse muscle. Transition of the Tm4-defined filaments from a predominsnatly longitudinal to a predominantly Z-LAC orientation is observed during the course of muscle regeneration. This study shows that Tm4 is a marker of regeneration and repair, in response to disease, injury and stress in skeletal muscle. Analysis of Tm5NM1 over-expressing (Tm5/52) and null (9d89) mice revealed that compensation between Tm genes does not occur in skeletal muscle. We found that the levels of cytoskeletal Tms derived from the δ-gene are not altered to compensate for the loss or gain of Tm5NM1 and that the localisation of Tm4 is unchanged in skeletal muscle of these mice. Also, excess Tm5NM1 is sorted correctly, localising to the ZLAC. This data correlates with evidence from previous investigations which indicates that Tm isoforms are not redundant and are functionally distinct (Gunning et al., 2005). Transgenic and null mice have also allowed the further elucidation of cytoskeletal Tm function in skeletal muscle. Analyses of these mice suggest a role for Tm5NM1 in glucose regulation in both skeletal muscle and adipose tissue. Tm5NM1 is found to colocalise with members of the glucose transport p fibres and analysis of both transgenic and null mice has shown an alteration to glucose uptake in adipose tissue. Taken together these data indicate that Tm5NM1 may play a role in the translocation of the glucose transport molecule GLUT4. In addition to this Tm5NM1 may play a role in adipose tissue regulation, since over-expressing mice found to have increased white adipose tissue and an up-regulation of a transcriptional regulator of fat-cell formation, PPAR-γ. / Doctor of Philosophy (PhD)

Thesis (M.Sc.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 194-209.

Lee, Yuen Shan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 81-102). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.iv / Table of contents --- p.vi / List of Figures --- p.ix / List of Abbreviations --- p.xi / Chapter Chapter 1. --- General introduction --- p.1 / Chapter Chapter 2. --- Literature review / Chapter 2.1 --- History of food allergy research --- p.3 / Chapter 2.2 --- Prevalence of food allergy --- p.4 / Chapter 2.3 --- Clinical symptoms of food allergy --- p.6 / Chapter 2.4 --- Mechanism of food allergy --- p.6 / Chapter 2.4.1 --- Properties of food allergens --- p.7 / Chapter 2.4.2 --- Exposures to food allergens in the gastrointestinal tract --- p.8 / Chapter 2.4.3 --- Oral tolerance and its relationship to food allergy --- p.9 / Chapter 2.4.4 --- Cellular mechanism of food allergy --- p.13 / Chapter 2.5 --- Studies on seafood allergies and allergens --- p.17 / Chapter 2.6 --- Use of animal models in the study of food allergy --- p.22 / Chapter 2.6.1 --- Selection of species and strain for developing animal models --- p.22 / Chapter 2.6.2 --- Parameters of sensitization protocol --- p.25 / Chapter 2.6.3 --- Lessons from animal models --- p.27 / Chapter 2.6.3.1 --- Investigations on pathogenesis of food allergy --- p.27 / Chapter 2.6.3.2 --- Studies on development of therapeutic strategies --- p.28 / Chapter Chapter 3. --- Characterization of hypersensitive responses to recombinant shrimp tropomyosin in mice / Chapter 3.1 --- Introduction --- p.30 / Chapter 3.2 --- Materials and Methods / Chapter 3.2.1 --- Preparation of the recombinant shrimp tropomyosin / Chapter 3.2.1.1 --- Expression of the recombinant shrimp tropomyosin --- p.32 / Chapter 3.2.1.2 --- Extraction and purification of the recombinant protein under native condition --- p.32 / Chapter 3.2.1.3 --- Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.33 / Chapter 3.2.1.4 --- Quantification of the recombinant protein and detection of level of endotoxin in the protein --- p.34 / Chapter 3.2.2 --- Characterization of hypersensitive responsesin mice / Chapter 3.2.2.1 --- Mice --- p.37 / Chapter 3.2.2.2 --- Sensitization and challenge of mice --- p.37 / Chapter 3.2.2.3 --- Assessment of systemic anaphylaxis responses --- p.38 / Chapter 3.2.2.4 --- Detection of shrimp tropomyosin specific IgE level --- p.39 / Chapter 3.2.2.5 --- Passive cutaneous anaphylaxis (PCA) test --- p.40 / Chapter 3.2.2.6 --- In vitro proliferation assay under stimulation of shrimp tropomyosin --- p.40 / Chapter 3.2.2.7 --- Cytokine profile of splenocytes --- p.42 / Chapter 3.2.2.8 --- Histological examination of small intestine --- p.44 / Chapter 3.2.2.9 --- Statistical analysis --- p.45 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Preparation of the recombinant shrimp tropomyosin --- p.47 / Chapter 3.3.2 --- Induction of systemic anaphylaxis responses after challenge --- p.48 / Chapter 3.3.3 --- Elevated level of shrimp tropomyosin specific IgE --- p.49 / Chapter 3.3.4 --- Passive cutaneous anaphylaxis (PCA) reactions --- p.50 / Chapter 3.3.5 --- Proliferation response of splenocytes under in vitro stimulation --- p.54 / Chapter 3.3.6 --- Cytokine profiles of restimulated splenocytes --- p.58 / Chapter 3.3.7 --- Histology of small intestine --- p.65 / Chapter 3.4 --- Discussion --- p.68 / Chapter Chapter 4. --- General conclusion --- p.78 / References --- p.81

Thesis (Ph.D.)--University of Western Sydney, 2007. / A thesis presented to the University of Western Sydney, College of Health and Science, School of Natural Sciences, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliographies.