Cell Biology Commons^™

The Effects Of Paclitaxel On Cellular Migration And The Cytoskeleton, Ashley Salguero-Gonzalez

Thinking Matters Symposium

In a clinical setting, some patients are exposed to an anti-cancer chemotherapy agent, paclitaxel. Cancerous cells undergo rapid, continuous cell division without control. Chemotherapy treatments try to slow and stop the uncontrollable cell division cycles and eliminate cancerous cells in the process. Paclitaxel serves as a treatment for some types of cancers, including lung, melanoma, bladder, and esophageal. Because it targets the cytoskeleton, paclitaxel can also influence cell migration. This project utilizes a cellular migration assay and an immunohistochemistry assay to analyze the effects of paclitaxel on the movement of cells and on the cytoskeleton of neuroglia rat cells with …

Molecular Mechanism Of Neurodegeneration Induced By 4-Nonylphenol, Michelle Alejandra Aranda

Open Access Theses & Dissertations

Neurodegeneration, a progressive loss of nerve cells, occurs in many neurological disorders, including Alzheimer's disease (AD) and Parkinson's diseases (PD), as well as in dementia. The pathogenesis of these diseases is unknown, and recent evidence suggests that environmental factors, which act as endocrine-disrupting compounds (EDCs) could play a significant role in developing the disease process. 4-Nonylphenol (4-NP), an EDC, and a ubiquitous environmental toxin has been shown to affect brain development and may cause neurodegeneration. 4-NP is produced in large quantities in the U.S. and used as raw materials for making detergents, pesticides, plastics, paints, cosmetics, rubber, and other industrial/household …

4-Nonylphenol Induces Neurodegeneration By Altering Cytoskeleton, Cynthia Carreon

Open Access Theses & Dissertations

4-nonylphenol (4-NP), an endocrine-disrupting compound (EDC), has been shown to affect brain development and may cause neurodegeneration. In the environment, 4-NP arises as a degradation product of alkylphenol polyethoxylates, compounds widely used as nonionic surfactants in commercial production, as well as in herbicides, pesticides, polystyrene plastics, and paints and has been shown to undergo a high level of accumulation in biological tissues. However, the mechanism by which 4-NP exerts its effect is not understood. Recent results from our laboratory indicate that Gβγ, an important component of the G protein-signaling pathway, induces neuronal outgrowth and differentiation by modulating microtubule (MT) assembly, …

A Mitochondria-Anchored Isoform Of The Actin-Nucleating Spire Protein Regulates Mitochondrial Division, Uri Manor, Sadie Bartholomew, Gonen Golani, Eric Christenson, Michael Kozlov, Henry Higgs, James Spudich, Jennifer Lippincott-Schwartz

Dartmouth Scholarship

Mitochondrial division, essential for survival in mammals, is enhanced by an inter-organellar process involving ER tubules encircling and constricting mitochondria. The force for constriction is thought to involve actin polymerization by the ER-anchored isoform of the formin protein inverted formin 2 (INF2). Unknown is the mechanism triggering INF2-mediated actin polymerization at ER-mitochondria intersections. We show that a novel isoform of the formin-binding, actin-nucleating protein Spire, Spire1C, localizes to mitochondria and directly links mitochondria to the actin cytoskeleton and the ER. Spire1C binds INF2 and promotes actin assembly on mitochondrial surfaces. Disrupting either Spire1C actin- or formin-binding activities reduces mitochondrial constriction …

A Novel Method For Studying Gene Regulatory Elements In Vivo Reveals Essential Roles For Intron Splicing In Neurofilament Gene Expression, Chen Wang

Legacy Theses & Dissertations (2009 - 2024)

Axon outgrowth requires coordinated expression of critical cytoskeletal genes in response to extracellular cues. The spatial and temporal expression of these genes is regulated transcriptionally and posttranscriptionally. Such regulation is largely mediated through the activity of cis-regulatory elements within the cytoskeletal DNAs and RNAs, which recruit specific sets of trans-factors such as DNA- and RNA-binding proteins, as well as microRNAs. To identify the functionally active cis-elements, characterize their dynamically changing sets of trans-factors, and investigate the association between the two sets of regulators in the context of an intact developing nervous system, one needs to combine appropriate in vivo strategies …

Plant Cytoskeleton: Della Connects Gibberellins To Microtubules, Ram Dixit

Biology Faculty Publications & Presentations

A new study reveals that DELLA proteins directly interact with the prefoldin complex, thus regulating tubulin subunit availability in a gibberellin-dependent manner. This finding provides a mechanistic link between the growth-promoting plant hormone gibberellin and cortical microtubule organization.

Subcellular Analysis Of The Disulfide Proteome In P66shc Expressing Nerve Cells, Tyler Cann

Electronic Thesis and Dissertation Repository

The longevity associated protein p66Shc has been suggested to regulate organismal lifespan through initiation of apoptotic pathways. Following stress-induced translocation into the mitochondria, p66Shc promotes increased reactive oxygen species (ROS) production and triggers poorly defined downstream signaling events that lead to decreased cell viability. Protein disulfide bonding has recently emerged as aROSdependent post-translational modification that regulates protein function and signaling processes. Using the mouse hippocampal HT-22 cell line, I sought to determine the changes in the disulfide proteome associated with p66Shc mediatedROSproduction. Through Redox 2D-SDSPAGEanalysis of mitochondrial and cytosolic extracts, redox sensitive proteins altered by p66Shc mediatedROSformation were identified. Of …

Computer Simulation And Mathematical Models Of The Noncentrosomal Plant Cortical Microtubule Cytoskeleton, Ezgi Can Eren, Natarajan Gautam, Ram Dixit

Biology Faculty Publications & Presentations

There is rising interest in modeling the noncentrosomal cortical microtubule cytoskeleton of plant cells, particularly its organization into ordered arrays and the mechanisms that facilitate this organization. In this review, we discuss quantitative models of this highly complex and dynamic structure both at a cellular and molecular level. We report differences in methodologies and assumptions of different models as well as their controversial results. Our review provides insights for future studies to resolve these controversies, in addition to underlining the common results between various models. We also highlight the need to compare the results from simulation and mathematical models with …

Septin Filaments Exhibit A Dynamic, Paired Organization That Is Conserved From Yeast To Mammals, Bradley S. Demay, Xiaobo Bai, Louisa Howard, Patricia Occhipinti, Rebecca A. Meseroll, Elias T. Spiliotis, Rudolf Oldenbourg, Amy S. Gladfelter

Dartmouth Scholarship

The septins are conserved, GTP-binding proteins important for cytokinesis, membrane compartmentalization, and exocytosis. However, it is unknown how septins are arranged within higher-order structures in cells. To determine the organization of septins in live cells, we developed a polarized fluorescence microscopy system to monitor the orientation of GFP dipole moments with high spatial and temporal resolution. When GFP was fused to septins, the arrangement of GFP dipoles reflected the underlying septin organization. We demonstrated in a filamentous fungus, a budding yeast, and a mammalian epithelial cell line that septin proteins were organized in an identical highly ordered fashion. Fluorescence anisotropy …

Rho Kinase Regulates Basement Membrane Dynamics To Coordinate Salivary Gland Branching Morphogenesis And Tissue Organization, William Patrick Daley

Legacy Theses & Dissertations (2009 - 2024)

Branching morphogenesis is a developmental mechanism utilized by many organs, including the salivary gland, lung, kidney, and mammary gland, to increase the epithelial surface area for secretion or absorption. The embryonic submandibular salivary gland (SMG) is a classic model for studying tissue morphogenesis in three dimensions ex vivo. Salivary gland development requires distinct but overlapping processes: morphogenesis, the actual physical rearrangement of cells into complex three dimensional structures, and cytodifferentiation, the process by which these cells begin to take on their own specialized function. Polarization, or the organization of cells into a cohesive tissue structure, also occurs concurrently during organ …

Biomimetic Actuators: Where Technology And Cell Biology Merge [Review Article], Michael Knoblauch, Winfried Peters

Winfried S. Peters