Life Sciences Commons^™

The Investigation Of Novel Bovine Oocyte-Specific Long Non-Coding Rnas And Their Roles In Oocyte Maturation And Early Embryonic Development, Jaelyn Zoe Current

Graduate Theses, Dissertations, and Problem Reports

Early embryonic loss is a significant factor in livestock species' infertility, resulting in an economic deficit. In cattle, the in vivo fertilization rate is ~90%, with an average calving rate of about 55%, indicating an embryonic-fetal mortality rate of roughly 35%. Further, 70-80% of total embryonic loss in cattle occurs during the first three weeks after insemination, particularly between days 7-16. Growing evidence indicates that the oocyte plays an active role in regulating critical aspects of the reproductive process required for successful fertilization, embryo development, and pregnancy. However, defining oocyte quality remains enigmatic. Recently, many have abandoned the notion that …

Defining The Role Of Rbbp4 In Oocyte Maturation And Preimplantation Development Using Trim-Away, Holly L. Barletta

Masters Theses

Retinoblastoma-binding protein 4 (RBBP4) is a subunit of chromatin remodeling factor 1 (CAF-1) and is essential for mammalian oocyte maturation, embryo survival, and embryo implantation. RBBP4 also localizes to the chromatin and is a ubiquitously expressed nuclear protein. Previous methods used to study this protein include short interfacing RNAs (siRNAs) and CRISPR/Cas9. These techniques have limitations such as determining an indirect depletion of proteins, may trigger compensatory mechanisms, and may not be useful in non-dividing primary cells. A new, acute, and rapid endogenous protein depletion technique called Trim-Away, can overcome these limitations. Trim-Away is also widely applicable since it can …

Pannexin 1 Inhibition Delays Maturation And Improves Development Of Bos Taurus Oocytes, Zachary Timothy Dye, Lauren Virginia Rutledge, Silvia Penuela, Paul William Dyce

Anatomy and Cell Biology Publications

© 2020 The Author(s). Background: Intercellular exchange between the oocyte and its surrounding cells within the follicular environment is critical for oocyte maturation and subsequent development. In vertebrates this exchange is facilitated through gap junctions formed by connexin membrane proteins. Another family of membrane proteins called pannexins are able to form single membrane channels that allow cellular exchanges with the extracellular environment. The most ubiquitously expressed and studied member, pannexin 1 (PANX1), has yet to be described thoroughly in female reproductive tissues or functionally studied during oocyte maturation. Here, we look into the expression of pannexin 1 in bovine cumulus-oocyte …

Characterization Of Ca2+ Influx Pathway(S) During Mouse Oocyte Maturation, Banyoon Cheon

Doctoral Dissertations

Ca²⁺ signaling induced at fertilization, also known as oscillations, is essential in mammalian eggs to initiate early embryonic development. The generation of the oscillations relies on optimization of Ca²⁺ toolkit components during oocyte maturation. In this dissertation, we intend to deepen our understanding of how this differentiation of the Ca²⁺ toolkit, especially those components associated with Ca²⁺ influx, is achieved during maturation, and how it contributes to the filling of the ER Ca²⁺ store during the maturation and fertilization. We first identified the expression and characterized the function of the components of the Store Operated …

Determining The Potential Activity Of Wnt Signaling During Zebrafish Oocyte Maturation, Nathan Pincus

Honors Program Theses

During maturation, the oocyte (immature egg) progresses from prophase I to metaphase II of meiosis and a multitude of cellular changes occur. In zebrafish, oocyte maturation is triggered by 17α,20β-dihydroprogesterone (DHP), which binds to a membrane-bound receptor, however the extent of communication between the oocyte and its environment is not fully understood. Wnt signaling pathways are known to regulate gene expression, cell behavior, cell adhesion, and cell polarity, as well as play an essential role in embryonic development. In this study, I investigated the potential activity of Wnt signaling pathways during zebrafish oocyte maturation by examining the gene expression of …

Evidence For The Requirement Of 14-3-3eta (Ywhah) In Meiotic Spindle Assembly During Mouse Oocyte Maturation, Santanu De, Douglas Kline

Biology Faculty Articles

Background

The 14-3-3 (YWHA) proteins are central mediators in various cellular signaling pathways regulating development and growth, including cell cycle regulation. We previously reported that all seven mammalian 14-3-3 isoforms are expressed in mouse oocytes and eggs and that, 14-3-3η (YWHAH) accumulates and co-localizes in the region of meiotic spindle in mouse eggs matured in vivo. Therefore, we investigated the role of 14-3-3η in spindle formation during mouse oocyte maturation.

Results

Examination of oocytes matured in vitro demonstrated that 14-3-3η accumulates in both meiosis I and II spindles. To explore if 14-3-3η interacts directly with α-tubulin in meiotic spindles, …

Expression Of 14-3-3 Protein Isoforms In Mouse Oocytes, Eggs And Ovarian Follicular Development, Santanu De, Jennifer Marcinkiewicz, Srinivasan Vijayaraghavan, Douglas Kline

Biology Faculty Articles

Background

The 14-3-3 (YWHA) proteins are a highly conserved, ubiquitously expressed family of proteins. Seven mammalian isoforms of 14-3-3 are known (β, γ, ε, ζ, η, τ and, σ). These proteins associate with many intracellular proteins involved in a variety of cellular processes including regulation of the cell cycle, metabolism and protein trafficking. We are particularly interested in the role of 14-3-3 in meiosis in mammalian eggs and the role 14-3-3 proteins may play in ovarian function. Therefore, we examined the expression of 14-3-3 proteins in mouse oocyte and egg extracts by Western blotting after polyacrylamide gel electrophoresis, viewed fixed …

Determining The Role Of Wnt Signaling In Zebrafish Oocyte Maturation Through Examination Of Β-Catenin And Dishevelled Mrna Concentrations, Nathan Pincus

Summer Research

During oocyte maturation, the oocyte progresses from prophase I to metaphase II of meiosis, and a multitude of other cellular changes occur1. Wnt singaling pathways are known to regulate gene expression, cell behavior, cell adhesion, and cell polarity, as well as play an essential role in embryonic development. Because of this, I am examining the role of Wnt signaling pathways in the earlier process of oocyte maturation, specifically by looking at two Wnt signaling pathway components: β-catenin (ctnnb1) and Dishevelled (dvl2). β-catenin is a an interesting protein to study because it plays a dual role as both a cell adhesion …

Determining The Origin Of Changing Β-Catenin Concentrations In Zebrafish Oocytes During Maturation, Nathan Pincus

Summer Research

During maturation, oocytes (immature eggs) progress from prophase I to metaphase II of meiosis, and a multitude of other cellular changes occur. β-catenin is a unique protein as it is involved in cell-cell adhesion when it is bound in plasma membrane complexes, and acts as a transcription factor when freed into the cytoplasm and allowed to move into the nucleus. β-catenin has been found to take part in signaling pathways such as the Wnt/β-catenin pathway, which inhibits β-catenin degradation, and subsequently regulates gene transcription. β-catenin has also been found to exist in distinct molecular forms depending on its role, which …

The Time Progression Of Bub1 And Cdc2 Activation In Zebrafish (Danio Rerio) During Egg Maturation, Julie Swinson

Summer Research

The genes bub1 and cdc20 are involved in regulation of meiotic arrest during maturation of the oocyte (immature egg). Meiotic arrest is important in oogenesis, the development of fertilizable eggs, and allows for identification of any DNA mutations or chromosome assembly errors, thus preventing damaged eggs from being ovulated. This study has examined the expression of spindle assembly checkpoint genes bub1 and cdc20. Oocytes were treated with DHP (hormone to induce maturation) or by nocodazole, a spindle destabilizing agent, and relative amounts of mRNA were measured using RT-PCR. These experiments will establish a timeline of bub1 and cdc20 activation …