Cell and Developmental Biology Commons^™

Cation Channels, Ca2+ Homeostasis, And Fertility In The Mouse, Goli Ardestani

Doctoral Dissertations

In mammals, fully grown immature oocytes, also known as germinal vesicle (GV), are arrested at prophase of meiosis I. Upon increase of the luteinizing hormone (LH), GV oocytes resume meiosis and reach the metaphase II (MII) stage of the second meiosis, a process known as oocyte maturation. These mature oocytes, henceforth referred to as eggs, are ovulated arrested at the MII stage, from which they are released at the time of fertilization. As in many other cells, Ca²⁺ homeostasis plays a pivotal role in oocytes during maturation and following fertilization, and it is therefore carefully regulated in these cells. …

Molecular Mechanisms Mediating Morphogenesis Of The Basal Epithelial Tissue Fold During Midbrain-Hindbrain Boundary Formation In Zebrafish, Mike Roger Visetsouk

Theses and Dissertations

ABSTRACT

MOLECULAR MECHANISMS MEDIATING MORPHOGENESIS OF THE BASAL EPITHELIAL TISSUE FOLD DURING MIDBRAIN-HINDBRAIN BOUNDARY FORMATION IN ZEBRAFISH

by

Mike Roger Visetsouk

The University of Wisconsin-Milwaukee, 2019

Under the Supervision of Jennifer H. Gutzman, PhD

The formation of a fully functional organism requires the morphogenesis of cell and tissue structures during development. It is important to understand the mechanisms that mediate morphogenesis, since cell and tissue structures are crucial to physiological function. Here, we studied basal epithelial tissue folding as a model to determine the mechanisms of morphogenesis. We investigated a highly conserved basal tissue fold known as the midbrain-hindbrain boundary …

Primary Cilium-Dependent Signaling Mechanisms, Rajasekharreddy Pala, Nedaa Alomari, Surya M. Nauli

Pharmacy Faculty Articles and Research

Primary cilia are hair-like organelles and play crucial roles in vertebrate development, organogenesis, health, and many genetic disorders. A primary cilium is a mechano-sensory organelle that responds to mechanical stimuli in the micro-environment. A cilium is also a chemosensor that senses chemical signals surrounding a cell. The overall function of a cilium is therefore to act as a communication hub to transfer extracellular signals into intracellular responses. Although intracellular calcium has been one of the most studied signaling messengers that transmit extracellular signals into the cells, calcium signaling by various ion channels remains a topic of interest in the field. …

Mammalian Egg Activation: The Roles Of Trpv3 Channels And Plcz1, Hoi Chang Lee

Doctoral Dissertations

Calcium channels at the plasma membrane have been suggested to mediate Ca²⁺ influx during egg activation. The transient receptor potential (TRP) Ca²⁺ channel, TRPV3, is differentially expressed in oocytes during maturation, being fully active at MII stage. Specific stimulation of TRPV3 channels in mouse eggs promotes Ca²⁺ influx sufficient to induce egg activation and parthenogenesis. In chapter 2, we explore the function and distribution dynamics of the TRPV3 channel protein during oocyte maturation. Using dsRNA, TrpV3 overexpression, and inhibitors of protein synthesis, we modified the native expression of the channel and showed that the TRPV3 protein is …

Calmodulin-Like Protein 38: A Component Of Ribonucleoprotein Particles During Hypoxic Stress Responses In Arabidopsis, Ansul Lokdarshi

Doctoral Dissertations

Waterlogging stress leads to a crisis in energy metabolism and the accumulation of toxic metabolites due to the hypoxic and/or anoxic environment associated with this condition. To respond and adapt to this situation, higher plants employ an integrated genetic program that leads to the induction of anaerobic response polypeptide genes that encode metabolic and signaling proteins involved in altering metabolic flow and other adaptive responses. The study presented here shows that the Arabidopsis thaliana calmodulin-like protein CML38 is calcium sensor protein that serves as a member of the core anaerobic response gene family and is involved in modulating the survival …

Role Of Non-Muscle Myosin Ii And Calcium In Zebrafish Midbrain-Hindbrain Boundary Morphogenesis, Srishti Upasana Sahu

Theses and Dissertations

Elucidating the molecular mechanisms that play a role in cellular morphogenesis is critical to our understanding of brain development and function. The midbrain-hindbrain boundary (MHB) is one of the first folds in the vertebrate embryonic brain and is highly conserved across species. We used the zebrafish MHB as a model for determining the molecular mechanisms that regulate these cell shape changes. Cellular morphogenesis is tightly regulated by signaling pathways that rearrange the cytoskeleton and produce mechanical forces that enable changes in cell and tissue morphology. The generation of force within a cell often depends on motor proteins, particularly non-muscle myosins …

The Atp2c2 Gene As Transcribed From A Novel Transcriptional Start Site In Pancreatic Acinar Cells, Caitlin M. Sullivan

Electronic Thesis and Dissertation Repository

Strict regulation of cytosolic Ca²⁺ is essential to regulated exocytosis and proper pancreatic acinar cell function, controlled in part by pumps that shuttle Ca²⁺ out of the cytosol. Our laboratory identified a novel isoform of Secretory Ca²⁺ ATPase 2 (SPCA2) containing only the carboxy terminus. Pancreatic SPCA2, is an approximately 17-20 kDa, protein encoded by the Atp2c2 gene and is completely absent in Mist1^-/- acini.. The focus of this thesis was to understand transcriptional regulation of Atp2c2 in the pancreas. Pancreatic Atp2c2 appears to be transcribed from an alternative transcriptional start site (TSS) and is regulated …

The Postsynaptic Regulation Of Synaptic Strength In Drosophila, Daniel Michael Gertner

Legacy Theses & Dissertations (2009 - 2024)

Postsynaptic Ca2+ plays an important role in synaptic homeostasis and synaptic plasticity. Postsynaptic Ca2+ signals have been shown to regulate synaptic transmission at the Drosophila larval neuromuscular junction (NMJ), however, these signals have not been well characterized. This will explore how these signals regulate synaptic strength and what channels are involved. In previous lab experiments Ca2+ transients were observed during evoked and spontaneous release (Desai and Lnenicka, 2011). It was further demonstrated that a reduction in synaptic strength occurs following synaptic stimulation. It was hypothesized that the increase in postsynaptic Ca2+ following synaptic stimulation activates the gCS and causes a …

Characterizing The Heavy Metal Chelator, Tpen, As A Ca2+ Tool In The Mammalian Oocyte, Robert A. Agreda Mccaughin

Masters Theses 1911 - February 2014

N,N,N’,N’-tetrakis-(2-Pyridylmethyl) ethylenediamine (TPEN) is a heavy metal chelator with high affinity for zinc. TPEN causes important responses in mammalian eggs. For example, these eggs are arrested at the MII stage by the Endogenous Mitotic Inhibitor 2 (Emi2), which prevents activation of the Anaphase Promoting Complex (APC) and degradation of Cyclin B. By chelating zinc, TPEN inactivates Emi2 and eggs undergo spontaneous exit of meiosis and egg activation. TPEN chelates Ca²⁺ with lower affinity, although in the Endoplasmic Reticulum (ER), where Ca²⁺ concentrations are high, TPEN may sequester Ca²⁺ preventing release into the cytoplasm. Initial exposure of TPEN …

Cell Surface-Binding Sites For Progesterone Mediate Calcium Uptake In Human Sperm, Peter F. Blackmore, Joseph Neulan, Frank Lattanzio, Stephen J. Beebe

Bioelectrics Publications

Recent studies (e.g. Blackmore, P. F., Beebe, S. J., Danforth, D. R., and Alexander, N.) (1990) J. Biol. Chem. 265, 1376-1380) have shown that in human sperm, progesterone produces a rapid increase in intracellular free calcium ([Ca2+]i) and an induction of the acrosome reaction (e.g. Osman, R. A., Andria, M. L., Jones, A. D., and Meizel, S. (1989) Biochem. Biophys. Res. Commun. 160, 828-833). In this study, the location of progesterone receptors on the cell surface of human sperm was identified using progesterone immobilized on bovine serum albumin (BSA) (progesterone 3-(O-carboxymethyl)oxime:BSA) as well as progesterone and its 3-O-carboxymethyloxime derivative. Using …