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Thesis (Ph.D.)--University of Adelaide, Dept. of Anatomical Sciences, 2004. / "August 2004" Bibliography: leaves 220-255.

Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed Mar. 23, 2009). Vita. Includes bibliographical references.

Thesis (Ph.D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 25, 2009) Vita. Includes bibliographical references.

Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xi, 97 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 68-70).

Thesis (M.A.)--Central Connecticut State University, 1999. / Thesis advisor: Kathy Martin. " ... in partial fulfillment of the requirements for the degree of Master of Arts in Biological Sciences." Includes bibliographical references (leaves 42-44).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 70-86). Also available via the Internet.

This thesis deals with the assembly and composition of cytoskeletal components in the mammalian organ of Corti. It mainly concentrates on large cell surface-associated microtubule bundles in certain supporting cells called inner pillar cells. Two distinct microtubule arrays assemble in each cell. One of the arrays spans the entire length of a cell (transcellular array) whereas the other is confined to its lower portion (basal array). The basal array is situated more than 10mum from the apically situated centrosomal region. Serial cross- sectional analyses indicate that the transcellular array elongates from the cell apex to the cell base but that the basal array elongates towards the cell apex and is nucleated at the cell base. However, antibodies to centrosomal proteins reveal that each inner pillar cell probably contains only one microtubule nucleating site which is situated in the apical centrosomal region. Therefore, basal array microtubules do not appear to be nucleated at the cell base. Assessment of microtubule polarities support this hypothesis; they provide evidence that both arrays have their plus ends (elongating ends) directed towards the cell base. A sophisticated assembly sequence which involves the escape and capture of centrosomally nucleated microtubules is proposed to account for the assembly of the basal array. The microtubules in the supporting cells are post-translationally modified. However, the microtubules of the neighbouring sensory hair cells are not post-translationally modified. Two kinds of cytokeratins are deployed in a cell type-specific manner in the supporting cells and may help to link the ends of micro tubule bundles to cell junctions.

Neurodegeneration in selected brain areas, associated with abnormal behavior of cytoskeletal proteins or altered organization of the cytoskeletal filament network, exhibits a characteristic feature of many neurodegenerative diseases. Therefore, focusing on analyzing the dynamics of cytoskeletal proteins under disease-relevant conditions using live cell imaging approaches could provide a better understanding of the cellular mechanisms underlying neurodegeneration. Fluorescence photoactivation (FPA) provides a novel tool to label and track living cells, organelles, or even single molecules in living systems in a spatio-temporal manner with high sensitivity. Fusion of photoactivatable fluorescence proteins to cytoskeletal proteins allows analyzing cytoskeletal dynamics in neurons in real-time and provides the unique opportunity to determine the effect of disease-relevant conditions on cytoskeletal dynamics in living neurons. Aim of the thesis was to study the motion of different cytoskeletal proteins: the microtubule associated protein tau and the growth associated actin-binding protein GAP-43. Expression of both proteins is developmentally regulated and may play an important role in neuronal polarization. Furthermore, both proteins show enrichment at the distal part of the neurite, the growth cone. The mechanisms, how distal trapping of tau and trafficking and enrichment of GAP-43 at the tip are regulated, are unclear. To scrutinize the dissipation of both proteins in living neurons, we constructed a panel of PAGFP-tagged fusion constructs and expressed them in differentiated PC12 cells as a neuronal model system. Using FPA in combination with computer-assisted image processing, we could identify the dissipation and trapping mechanisms of both proteins. The data indicate that FPA provides a useful and versatile approach to determine protein distribution in living cells during development and disease-like conditions.