Cell Biology Commons^™

Potential Counter Regulatory Effects Of A Gut Microbiota Metabolite In Alleviating Down-Regulation Krüppel-Like Factor 4 In Intestinal Inflammation, Ylva Forslund

Theses, Dissertations and Capstones

Inflammatory bowel disease (IBD) is a medical condition characterized by chronic inflammation of the intestinal epithelium. Krüppel-like factor 4 (KLF4), a zinc finger transcription factor, is vital for maintaining intestinal epithelial homeostasis. KLF4 promotes differentiation of goblet cells that generate the protective mucus layer. Reduced goblet cell number and defective mucus layer are associated with IBD. Shortchain fatty acids (SCFA) are known to play an important role in the maintenance of a strong and healthy intestinal epithelial layer and also in goblet cell differentiation. However, whether the positive effects of SCFAs on goblet cells are mediated, at least partly, via …

Development Of Endoplasmic Reticulum Targeted Probes And Red Fluorescent Probes For Detecting Zinc, Drew Maslar

Electronic Theses and Dissertations

Zinc (Zn²⁺) is the second most abundant transition metal in the body and is important in various biological functions. Fluorescent sensors based on circularly permuted fluorescent proteins (cpFPs) have been previously made to detect labile, or unbound, Zn²⁺ within the cytoplasm of cells. These sensors have proven invaluable for studying Zn²⁺, however, these sensors are limited to their use in the cytoplasm and by the fact that only green cpFP have been utilized to create fluorescent Zn²⁺ sensors. In this thesis, we use a combination of peptide targeting sequences, site-directed mutagenesis, and rational design …

Characterizing Ferroptosis Pathways In In Vitro Motor Neuron Models, Alejandra Martinez

Theses and Dissertations

Ferroptosis is a non-apoptotic regulated form of cell death driven by the toxic accumulation of lipid peroxides and the presence of iron. The mechanism by which ferroptosis operates requires further investigation; here I will discuss the findings regarding the role of ferroptosis in different cellular models as well as the genes that may be involved with either promoting or hindering the ferroptotic pathway. NSC-34 is a hybrid cell line of neuroblastoma and primary spinal cord cells that can be differentiated into a motor neuron-like state allowing the characterization of ferroptosis in two distinct cellular conditions. Additionally, iNIL cells are a …

Expansion Microscopy To Visualize Cell-Cycle Events In The Abbreviated Cell Cycle In Caenorhabditis Elegans (Roundworm) Germline Stem Cells, Taylor Campbell

Master's Theses and Doctoral Dissertations

The abbreviated cell cycle is a poorly understood form of the cell cycle essential for genome stability in stem cells. To visualize cell-cycle events in the abbreviated cell cycle, we optimized a protocol for expansion microscopy in stem cells of the reproductive system of the model organism C. elegans. Optimizations included development of new mounting techniques and modifications to DNA staining methods. These optimizations produced brighter samples that were easier to find and focus on at the microscope. These optimizations, combined with future labeling of DNA replication, will expand our understanding of how cells with an abbreviated cell cycle maintain …

Fxs-Causing Point Mutations In Fmrp Disrupt Neuronal Granule Formation And Function, Emily L. Starke

Electronic Theses and Dissertations

Fragile X Syndrome (FXS) is a neurodevelopmental disorder caused by the disruption of Fragile X Mental Retardation Protein (FMRP) function in neurons, affecting nearly 1 in 7,500 individuals. Although FXS typically occurs from a complete loss of FMRP expression due to a CGG trinucleotide expansion within the 5’UTR of the FMR1 gene, single nucleotide polymorphisms (SNPs) within the KH domains of FMRP have been shown to severely disrupt FMRP function. FMRP is an RNA-binding translation repressor that interacts with ~4% of the neuronal transcriptome. Many target mRNAs encode for proteins important for regulating synaptic processes and modulate synaptic plasticity. It …

Intestinal Endothelial Cells Promote Hiv-1 Infection In Resting Cd4+ T-Cells Without Causing T-Cell Activation, Jessica Eddy, Rachel Chee, Esther Park, Anding Shen

Summer Research

It is generally understood that HIV-1 does not effectively infect resting CD4+ T cells, and latent infection in those cells may arise when activated infected CD4+ T Cells return to a resting state. However, we found that stimulation by intestinal endothelial cells (IEC) can render resting CD4+ T cells permissible for direct HIV infection. Upon infection, these stimulated T cells remain largely phenotypically inactivated. This study was centered around HIV-1 infection in the context of intestinal tissues, as HIV has extensive gut pathology. Endothelial cells are abundant in mucosal tissues and would have direct, constant interactions with CD4+ T Cells …

Association Between Plasma Genistein And Health-Related Quality Of Life In Breast Cancer Survivors, Tran Pham

Honors Undergraduate Theses

According to the American Cancer Society, breast cancer is the most commonly diagnosed cancer and is the second leading cause of cancer death in American women. Breast cancer screenings and improvement in treatments have resulted in the rising number of survivors in the recent decade. This urged the need for post-diagnosis lifestyle changes to improve breast cancer patients' quality of life. Many studies found soy food, the primary dietary source of phytoestrogens, has a protective effect against breast cancer recurrence and mortality. Dietary phytoestrogens can be classified into two groups: isoflavones and lignans. Daidzein and genistein were identified as the …

Tracking The Subcellular Localization Of Surface Proteins In Staphylococcus Aureus By Immunofluorescence Microscopy, Salvatore J. Scaffidi, Mac A. Shebes, Wenqi Yu

Molecular Biosciences Faculty Publications

Surface proteins of Staphylococcus aureus and other Gram-positive bacteria play essential roles in bacterial colonization and host-microbe interactions. Surface protein precursors containing a YSIRK/GXXS signal peptide are translocated across the septal membrane at mid-cell, anchored to the cell wall peptidoglycan at the cross-wall compartment, and presented on the new hemispheres of the daughter cells following cell division. After several generations of cell division, these surface proteins will eventually cover the entire cell surface. To understand how these proteins travel from the bacterial cytoplasm to the cell surface, we describe a series of immunofluorescence microscopy protocols designed to detect the stepwise …

Dcaf14 Promotes Stalled Fork Stability To Maintain Genome Integrity, Arik Townsend, Gabriella Lora, Justin Engel, Neysha Tirado-Class, Huzefa Dungrawala

Molecular Biosciences Faculty Publications

No abstract provided.

The Characterization Of The Function(S) Of Crag In Basement Membrane Polarity, Hemin Pankajkumar Shah

Graduate Research Theses & Dissertations

The abundant epithelial cells play various roles in the development and maintenance of an organism, and their apical-basolateral polarity is a unique characteristic that is imperative to their function and integrity. This polarity is maintained via various environmental cues and tightly regulated intracellular trafficking, where the presence of the basement membrane (BM) provides a basal cue. The BM is a specialized extracellular matrix (ECM) secreted by the epithelial cells, which accumulates on the basal side and serves as their mechanical anchorage. Although the BM is of paramount importance in the apical-basolateral polarity and the loss of BM’s integrity is a …

Stobe Photography Mapping Of Cell Membrane Potential With Nanosecond Resolution, Allen S. Kiester, Bennett L. Ibey, Zachary N. Coker, Andrei G. Pakhomov, Joel N. Bixler

Bioelectrics Publications

The ability to directly observe membrane potential charging dynamics across a full microscopic field of view is vital for understanding interactions between a biological system and a given electrical stimulus. Accurate empirical knowledge of cell membrane electrodynamics will enable validation of fundamental hypotheses posited by the single shell model, which includes the degree of voltage change across a membrane and cellular sensitivity to external electric field non-uniformity and directionality. To this end, we have developed a high-speed strobe microscopy system with a time resolution of ~ 6 ns that allows us to acquire time-sequential data for temporally repeatable events (non-injurious …

Impact Of Targeting Glycosylated Ceramides On Tumorigenic Properties, And Characterization Of Sphingolipids In Head And Neck Tumors, Katherine E. Hylton

Theses and Dissertations

Sphingolipids play a crucial role in signaling, membrane structure, and migration, making them important molecules in cancer development, metastasis, and drug resistance. While some sphingolipids have been associated with pro-apoptotic or pro-survival behaviors, the role of many sphingolipids in cancer remains poorly defined. Chapter 1 of this study investigated the impact of three enzymes that compose most of the ceramide to Lc3 ceramide pathway – UGCG, GBA, and B3GNT5 – and how their alteration impacts chemoresistance and basal membrane invasion in vitro. It was found that the CΒE-induced inhibition of GBA, which converts glucosylceramide to ceramide, has no effects on …

Mimicking The Effect Of Prolactin On Stat3/Stat5 Activity In Breast Cancer, Jennifer N. Barbuto, Sarah R. Walker

Honors Theses and Capstones

Signal transducers and activators of transcription (STAT) 3 and 5 are commonly constitutively activated in breast cancer. STAT5 can outcompete STAT3 and reduce cell proliferation and metastasis. STAT5 activation is stimulated by prolactin, a natural hormone that can be harmful at high levels. The aim of this study is to identify some possible previously developed drugs that mimic the effect of prolactin and STAT5 without the added risk in MDA-MB231 breast cancer cells. Using the CLUE database query app and STAT5 up- and downregulation signatures, three drugs (X, K, and M) were chosen based on their similarity in signatures to …

Exploring The Connection Between The Spontaneous Regression Seen In Neuroblastomas, Hypertumors, And Reactive Oxygen Species, Shahad Musa, Manitha Mulpuru

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Peto’s Paradox is defined as the lack of correlation between larger animals and cancer risk. Under the assumption that all cells have equal risk of becoming cancerous, larger animals should have greater rates of cancer. However, the inverse is true. Determining the cause of this variation may allow a supplemental approach to cancer treatment. A combination of two reasons may account for this correlation including hypertumors and metabolism. Hypertumors, or cheater cells, are hypothesized to suppress cancer growth through spontaneous autophagic degradation and overexpression of the RAS g-protein. Both of these characteristics are exhibited in Neuroblastomas. An anticancer drug used …

Study Of Primary Cilium Structure And Intraflagellar Transport, Shufeng Sun

Legacy Theses & Dissertations (2009 - 2024)

Primary cilia are hair-like protrusions that stem from the basal bodies in the cytoplasm and extend into the extracellular space to sense signals. Intraflagellar transport (IFT) functions to transport cargo molecules into and out of the ciliary compartment to assemble, maintain, and disassemble the cilia. Accurate knowledge of the three-dimensional (3D) structure of primary cilia and precise details of the IFT profile is the foundation for understanding the sensory functions of primary cilia. This work covers three aspects of primary cilia. Firstly, we obtained and analyzed the overall 3D architecture of the complete primary cilia axoneme region using serial section …

Clinical Significance, Functional Role And Molecular Mechanism Of 2’-O-Methyltransferase Ftsj3 In Promoting Cancer Progression, Morenci Manning-Powell

Wayne State University Dissertations

2’-O-methylation (2’-O-Me), one of the most common modifications within RNA, has multiple roles in modulating RNA structure, stability, and interactions, as well as gene transcription and translation. We previously performed integrative genomic and transcriptomic analysis of 58 RNA methyltransferases, and identified FTSJ3 (FtsJ RNA 2ʹ-O-methyltransferase 3) as significantly amplified/overexpressed in breast cancer. Knockdown of FTSJ3 inhibits breast cancer cell growth in vitro. However, the clinical significance, functional role, and molecular mechanism of FTSJ3 in human cancer remains to be elucidated. In the present study, we first analyzed the differential mRNA and protein expression of FTSJ3 between tumor and normal tissues …

Human Regulatory T Cells Control Inflammation From Effector T Cells In Prediabetes, Rui Liu

Theses and Dissertations--Pharmacy

Type 2 diabetes (T2D) is a chronic low-grade inflammatory disease. A T cell cytokine profile (Th17) from PBMCs can distinguish obese T2D from obese non-diabetes subjects. Individual T cell subsets interact with each other and the diverse subsets jointly determine overall inflammation. Cellular metabolism drives cytokine production of CD4⁺ T cells, and therefore contributes to inflammation in T2D. However, specific changes in metabolism and function of CD4⁺ T cells during the progression from lean healthy to obese and diabetic stages in people have not been clarified.

We hypothesize that human regulatory T cells (Treg) impact metabolism of effector …

Elucidating The Role Of The Tyrosine Phosphatase, Shp-2, In Regulation Of Pd-L1 Expression In Non-Small Lung Cancer Using Both Biochemical Analyses And Real-World Genomic Information, Keller Toral

Theses and Dissertations--Pharmacy

Immune checkpoint inhibitors (ICIs), especially those that target programmed cell death protein 1 (PD-1) and programmed cell death ligand-1 (PD-L1), have been shown to provide substantial clinical benefit in many patients with non-small cell lung cancer (NSCLC). While these therapeutic agents can be highly effective in the correct context, the biological systems that malignant cells draft from normal activities of the cell are poorly characterized. Tumor cell-specific expression of PD-L1 is likely important for clinical benefit from PD-1 and PD-L1 inhibitors. It is known that PD-L1 is inappropriately expressed in many cancers harboring mutations in the RAS family of genes. …

Cop9 Signalosome Component Csn-5 Promotes Accumulation And Function Of Stem Cell Regulators Fbf-1 And Fbf-2, Emily Osterli

Graduate Student Theses, Dissertations, & Professional Papers

RNA-binding proteins FBF-1 and FBF-2 (FBFs) are required for stem cell maintenance in C. elegans, although the mechanisms by which FBFs protein levels are regulated remain unknown. Using a yeast two-hybrid screen, we identified an interaction between both FBFs and CSN-5, a component of the COP9 (constitutive photomorphogenesis 9) signalosome. This highly conserved COP9 complex can affect protein stability through a range of mechanisms including deneddylation, deubiquitination, and phosphorylation (Wolf et al., 2003). Mapping protein-protein interactions between FBFs and CSN-5 suggested that the MPN (Mpr1/Pad1 N-terminal) metalloprotease domain of CSN-5 interacts with the RNA-binding domain of FBFs at physiologically …

Cold-Induced Metabolic Changes In Lean, Nag-1 Transgenic Mice, Rachel J. Davey

All Master's Theses

Obesity is a multifaceted metabolic disorder with severe worldwide public health consequences. While obesity can often be treated using diet and exercise, there are complex genetic interactions driving obesity that don’t always respond to such changes. One important research focus for addressing genetic factors is activating brown adipose tissue which increases thermogenesis, the process of burning stored fats to generate heat. Cold exposure is a known way to activate brown adipose tissue through b3-adrenergic signaling. This signaling pathway causes an upregulation of thermogenesis in brown adipocytes and beige adipocytes, which is white adipose tissue that “browns” and becomes metabolically active. …