Life Sciences Commons^™

Perfluorooctane Sulfonate (Pfos)-Induced Disruption Of Mitochondrial Activity And Cell Adhesion In Liver Cells, Phuong Dam Nam Tran

Graduate Theses/Dissertations

Perfluorooctane sulfonate (PFOS) is a persistent environmental pollutant associated with potential hepatoxic effects and other health risks. Despite its widespread distribution, the mechanisms underlying its toxicities remain to be fully understood. To investigate PFOS toxicology, my study utilized HepG2 and THLE-2 human hepatic cell models to replicate conditions reflecting PFOS accumulation in the liver. Cell viability, cell stress, and cell death assays were conducted to assess the toxicological influence of the chemical on both cell lines. Total RNA extraction was performed, followed by cDNA sequencing, and RT-qPCR. The XTT viability assay revealed a dose-dependent decrease in number of viable cells …

The C-Terminal Phdvc5hch Tandem Domain Of Nsd2 Is A Combinatorial Reader Of Modified H3k4 And Tri-Methylated H3k27 That Regulates Transcription Of Cell Adhesion Genes In Multiple Myeloma, Andrea Berardi, Charlotte Leonie Kaestner, Michela Ghitti, Giacomo Quilici, Paolo Cocomazzi, Jianping Li, Federico Ballabio, Chiara Zucchelli, Stefan Knapp, Jonathan Licht, Giovanna Musco

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Histone methyltransferase NSD2 (MMSET) overexpression in multiple myeloma (MM) patients plays an important role in the development of this disease subtype. Through the expansion of transcriptional activating H3K36me2 and the suppression of repressive H3K27me3 marks, NSD2 activates an aberrant set of genes that contribute to myeloma growth, adhesive and invasive activities. NSD2 transcriptional activity also depends on its non-catalytic domains, which facilitate its recruitment to chromatin through histone binding. In this study, using NMR, ITC and molecular dynamics simulations, we show that the tandem PHD domain of NSD2 (PHDVC5HCHNSD2) is a combinatorial reader of unmodified histone H3K4 and tri-methylated H3K27 …

Cams In Command: Aging Brain Macrophages Fine-Tune Stroke Immune Responses, Rodney M Ritzel, Danye Jiang, Louise D Mccullough

Faculty, Staff and Student Publications

Central nervous system-associated macrophages (CAMs) are a unique subset of immune cells located at the interface between the blood and the brain parenchyma. In a recent study in mice, Levard and colleagues found that CAMs regulate immune cell trafficking, endothelial activation, and antigen presentation following stroke exclusively in aged animals, underscoring the importance of using translationally relevant models for studying age-related diseases.

Role Of Kindlin 2 In Prostate Cancer, Katarzyna Bialkowska, Lamyae El Khalki, Priyanka Rana, Wei Wang, Daniel Lindner, Yvonne Parker, Lucia Languino, Dario Altieri, Elzbieta Pluskota, Khalid Sossey-Alaoui, Edward Plow

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Kindlin-2 is a cytoskeletal adapter protein that is present in many different cell types. By virtue of its interaction with multiple binding partners, Kindlin-2 intercalates into numerous signaling pathways and cytoskeletal nodes. A specific interaction of Kindlin-2 that is of paramount importance in many cellular responses is its direct binding to the cytoplasmic tails of integrins, an interaction that controls many of the adhesive, migratory and signaling responses mediated by members of the integrin family of cell-surface heterodimers. Kindlin-2 is highly expressed in many cancers and is particularly prominent in prostate cancer cells. CRISPR/cas9 was used as a primary approach …

Spontaneous Alignment Of Myotubes Through Myogenic Progenitor Cell Migration, Lauren E. Mehanna, Adrianna R. Osborne, Charlotte A. Peterson, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

In large-volume muscle injuries, widespread damage to muscle fibers and the surrounding connective tissue prevents myogenic progenitor cells (MPCs) from initiating repair. There is a clinical need to rapidly fabricate large muscle tissue constructs for integration at the site of large volume muscle injuries. Most strategies for myotube alignment require microfabricated structures or prolonged orientation times. We utilize the MPC’s natural propensity to close gaps across an injury site to guide alignment on collagen I. When MPCs are exposed to an open boundary free of cells, they migrate unidirectionally into the cell-free region and align perpendicular to the original boundary …

Comparative Characteristics Of Integrin Αdβ2 Binding To Native Fibrinogen And Fibrinogen Modified By Dha Oxidation During Inflammation, Ajibola Ilesanmi

Electronic Theses and Dissertations

2-ω-carboxyethylpyrrole (CEP) is a product of docosahexaenoic acid (DHA) oxidation, which forms covalent adducts with different proteins. CEP-modified proteins can interact with macrophage receptor, integrin αDβ2. This study aims to compare αDβ2 binding to its physiological ligand, fibrinogen, and CEP-modified fibrinogen, which is formed during inflammation. We hypothesize that modification of fibrinogen changes its ligand-binding properties to integrin αDβ2 which can affect macrophage migration and retention. Recombinant αD I-domain and αDβ2-transfected HEK293 cells were used for the experiments. Using biolayer interferometry, we found that the affinity of αD I-domain binding to fibrinogen-CEP was higher than fibrinogen and inhibited by the …

The Alpha7 Integrin Subunit In Astrocytes Promotes Endothelial Blood-Brain Barrier Integrity, Zhihua Chen, Jack R Kelly, John E Morales, Raymond C Sun, Arpan De, Dean J Burkin, Joseph H Mccarty

Faculty, Staff and Student Publications

The blood-brain barrier (BBB) is a vascular endothelial cell boundary that partitions the circulation from the central nervous system to promote normal brain health. We have a limited understanding of how the BBB is formed during development and maintained in adulthood. We used quantitative transcriptional profiling to investigate whether specific adhesion molecules are involved in BBB functions, with an emphasis on understanding how astrocytes interact with endothelial cells. Our results reveal a striking enrichment of multiple genes encoding laminin subunits as well as the laminin receptor gene Itga7, which encodes the alpha7 integrin subunit, in astrocytes. Genetic ablation of Itga7 …

Ubiquitination Of The Protocadherin-Γa3 Variable Cytoplasmic Domain Modulates Cell-Cell Interaction, Albert Ptashnik, Nicole Lamassa, Aliya Mambetalieva, Emily Schnall, Mike Bucaro, Greg R. Phillips

Publications and Research

The family of ∼60 clustered protocadherins (Pcdhs) are cell adhesion molecules encoded by a genomic locus that regulates expression of distinct combinations of isoforms in individual neurons resulting in what is thought to be a neural surface “barcode” which mediates same-cell interactions of dendrites, as well as interactions with other cells in the environment. Pcdh mediated same-cell dendrite interactions were shown to result in avoidance while interactions between different cells through Pcdhs, such as between neurons and astrocytes, appear to be stable. The cell biological mechanism of the consequences of Pcdh based adhesion is not well understood although various signaling …

Gamma Protocadherin Synaptic Localization And Intracellular Trafficking Is Consistent With Distinct Adhesive And Anti-Adhesive Roles In Development, Nicole Lamassa

Dissertations, Theses, and Capstone Projects

Clustered protocadherins (Pcdhs) constitute a family of cell adhesion molecules with approximately 60 Pcdh genes clustered in a 1 MB locus on chromosome 5q31 in humans. The Pcdh gene cluster is subdivided into α, β, and γ subclusters which encode related proteins. Individual neurons activate different subsets of Pcdh-α, Pcdh-β and Pcdh-γ genes by epigenetic mechanisms to generate distinct Pcdh adhesive units expressed by each neuron. This is thought to serve as a “surface barcode” for single-cell identity and synaptic recognition in the nervous system. The actual role for Pcdhs in neural development is still relatively unknown and different roles …

Cyclase-Associated Protein 1 (Cap1) In Cyclic Adenosine Monophosphate (Camp) And Protein Kinase C (Pkc) Signals To Regulate Cancer Cell Functions, Lokesh Kalki Mani Sai Akana

Student Theses and Dissertations

Cyclase-Associated Protein 1 (CAP1) is an actin-regulating protein that promotes actin dynamics and is also involved in cell adhesion and proliferation as well as implicated in human cancers. We previously found that phosphorylation at the Ser307/Ser309 tandem regulatory site on CAP1 is critical for CAP1 functions in breast and pancreatic cancer cells. We silenced CAP1 through RNAi in HCT116 and SW480 colon cancer cells as confirmed in Western blotting. We have found that depletion of CAP1 led to reduced FAK (Focal Adhesion Kinase) activity and matrix adhesion in SW480 cells, while it stimulated FAK activity and cell adhesion in HCT116 …

Potential Regulation Of Breast Cancer Invasion By Thymidine Kinase 1, Eliza E. Bitter, Rachel M. Morris, Toni O. Mortimer, Kai Barlow, Abigail Schekall, Michelle H. Townsend, Jonathan Skidmore, Brett E. Pickett, Kim L. O'Neill

Library/Life Sciences Undergraduate Poster Competition 2022

Breast cancer is the most common cancer in women and is largely treatable within the early stages of the disease. However, patient mortality drastically declines as the tumor begins to invade other tissues and metastasize, making aggressive phenotypes especially problematic to treat. Such treatment typically requires an aggressive and decisive multidisciplinary approach. The recent expansion of immunotherapy as a viable treatment option has greatly improved treatment outcomes, especially with aggressive breast cancer phenotypes. Thymidine kinase 1 (TK1) is a DNA salvage pathway enzyme that is highly expressed during S phase and involved in cell cycle repair. Past studies indicated that …

The Role Of Daam1 In Kidney Development, Vanja Krneta-Stankic

Dissertations and Theses (Open Access)

Kidneys, like most organs in our bodies, consist of a network of epithelial tubules. Kidney tubules are called nephrons, and their morphology is important for kidney function. Nephrons develop from mesodermally derived aggregates of progenitor cells. The nephric progenitors organize into nephric tubules lined with hair-like sensory projections called cilia. Many diseases of the kidney are characterized by abnormal nephron morphology with current treatment aimed at symptom control. To understand the mechanisms underlying kidney diseases and achieve the development of novel therapies, a better understanding of how nephrons develop is needed. Although the actin cytoskeleton is critical for cell behaviors …

The Role Of Daam1 In Kidney Development, Vanja Krneta-Stankic

Dissertations and Theses (Open Access)

Kidneys, like most organs in our bodies, consist of a network of epithelial tubules. Kidney tubules are called nephrons, and their morphology is important for kidney function. Nephrons develop from mesodermally derived aggregates of progenitor cells. The nephric progenitors organize into nephric tubules lined with hair-like sensory projections called cilia. Many diseases of the kidney are characterized by abnormal nephron morphology with current treatment aimed at symptom control. To understand the mechanisms underlying kidney diseases and achieve the development of novel therapies, a better understanding of how nephrons develop is needed. Although the actin cytoskeleton is critical for cell behaviors …

Dynamic Phosphorylation And Dephosphorylation Of Cyclase-Associated Protein 1 By Antagonistic Signaling Through Cyclin-Dependent Kinase 5 And Camp Are Critical For The Protein Functions In Actin Filament Disassembly And Cell Adhesion, Haitao Zhang, Auburn Ramsey, Yitong Xiao, Uddhab Karki, Jennifer Y. Xie, Jianfeng Xu, Thomas Kelly, Shoichiro Ono, Guo-Lei Zhou

Arkansas Biosciences Institute

yclase-ssociated rotein (CAP1) is a conserved actin-regulating protein that enhances actin filament dynamics and also regulates adhesion in mammalian cells. We previously found that phosphorylation at the Ser307/Ser309 tandem site controls its association with cofilin and actin and is important for CAP1 to regulate the actin cytoskeleton. Here, we report that transient Ser307/Ser309 phosphorylation is required for CAP1 function in both actin filament disassembly and cell adhesion. Both the phosphomimetic and the nonphosphorylatable CAP1 mutant, which resist transition between phosphorylated and dephosphorylated forms, had defects in rescuing the reduced rate of actin filament disassembly in the CAP1 knockdown HeLa cells. …

Origins Of Animal Cell Adhesion, Jennyfer Mora Mitchell

Electronic Theses and Dissertations

A fundamental requirement for multicellularity is cell adhesion. This includes mechanisms by which cells adhere to each other and to their secreted extracellular matrix (ECM). Two well characterized adhesion complexes in animals include: 1) adherens junctions (AJs), which are involved in cell-cell adhesion and composed of cadherin receptors, p120-, α- and β-catenin, and 2) focal adhesions (FAs), which are involved in cell-ECM adhesion and include proteins such as integrins, vinculin, paxillin, talin and focal adhesion kinase (FAK). The molecular components of AJs are widely conserved in animals, and largely absent in non-animals. In contrast, the molecular components of FAs have …

Structure, Dynamics, And Regulation Of Collective Cell Migration, Andrew J. Loza

Arts & Sciences Graduate Student Theses and Dissertations

Collective migration is the process by which cells organize individual motions to productively migrate as a group and plays a fundamental role in organism development, tissue regeneration, and cancer invasion. In development, coordinated migration facilitates the formation of complex organ structures and is required for proper dissemination of neural crest cells throughout an organism. After injury, this process allows breaches in epithelial layers to be repaired while maintaining tissue integrity, and in cancer, collective behavior enhances invasion of tumor cells into the surrounding tissue. Chapter 1 provides an introduction for the role of collective migration across an organism’s lifespan, the …

The Study Of The Functions And Regulation Of Mammalian Cap1 (Cyclase-Associated Protein 1), Haitao Zhang

Student Theses and Dissertations

CAP is a conserved actin-binding protein with versatile roles in promoting actin dynamics across species. Mammalian CAPs had been understudied compared to the first identified yeast homologues; their cellular functions remained to be better established. Moreover, CAP function regulation remained a completely uncharted area. Recent studies also implicated CAP in the invasiveness of human cancers. However, some of the evidence was not convincing and further studies were needed. The present study established and identified new cellular functions for mammalian CAP1, identified a regulatory mechanism as phosphorylation at the S307/S309 tandem site along with the cell signals controlling both phosphorylation and …

Effects Of Anchor Structure And Glycosylation Of Fcî³ Receptor Iii On Ligand Binding Affinity, Ning Jiang, Wei Chen, Prithiviraj Jothikumar, Jaina M. Patel, Rangaiah Shashidharamurthy, Periasamy Selvaraj, Cheng Zhu

PCOM Scholarly Works

Isoforms of the Fcγ receptor III (FcγRIII or CD16) are cell surface receptors for the Fc portion of IgG and important regulators of humoral immune responses. Different ligand binding kinetics of FcγRIII isoforms are obtained in three dimensions by surface plasmon resonance and in two dimensions by a micropipette adhesion frequency assay. We show that the anchor structure of CD16 isoforms isolated from the cell membrane affects their binding affinities in a ligand-specific manner. Changing the receptor anchor structure from full to partial to none decreases the ligand binding affinity for human IgG1 (hIgG1) but increases it for murine IgG2a …

Elevated Integrin Α6Β4 Expression Is Associated With Venous Invasion And Decreased Overall Survival In Non-Small Cell Lung Cancer, Rachel L. Stewart, Dava West, Chi Wang, Heidi L. Weiss, Tamas S. Gal, Eric B. Durbin, William O'Connor, Min Chen, Kathleen L. O'Connor

Pathology and Laboratory Medicine Faculty Publications

Lung cancer carries a poor prognosis and is the most common cause of cancer-related death worldwide. The integrin α6β4, a laminin receptor, promotes carcinoma progression in part by cooperating with various growth factor receptors to facilitate invasion and metastasis. In carcinoma cells with mutant TP53, the integrin α6β4 promotes cell survival. TP53 mutations and integrin α6β4 overexpression co-occur in many aggressive malignancies. Because of the high frequency of TP53 mutations in lung squamous cell carcinoma (SCC), we sought to investigate the association of integrin β4 expression with clinicopathologic features and survival in non–small cell lung cancer (NSCLC). We constructed …

Kin Discrimination In Dictyostelium Social Amoebae, Joan E. Strassmann

Biology Faculty Research

Presentation delivered at the symposium Evidence of Taxa, Clone, and Kin Discrimination in Protists: Ecological and Evolutionary Implications, VII European Congress of Protistology, University of Seville, 5–10 September 2015, Seville Spain.

Evolved cooperation is stable only when the benefactor is compensated, either directly or through its relatives. Social amoebae cooperate by forming a mobile multicellular body in which, about 20% of participants ultimately die to form a stalk. This benefits the remaining individuals that become hardy spores at the top of the stalk, together making up the fruiting body. In studied species with stalked migration, P. violaceum, D. purpureum, and …

Cytotoxicity And Antibiofilm Activity Of Sio2/Cellulose Derivative Hybrid Materials Containing Silver Nanoparticles, Tsvetelina Angelova, Nadezhda Rangelova, Veselina Uzunova, Nelly Georgieva, Tonya Andreeva, Albena Momchilova, Rumiana Tzoneva, Rudolf Müller

Turkish Journal of Biology

Hybrid materials based on tetraethyl orthosilicate (TEOS), hydroxypropyl cellulose (HPC), or hydroxypropyl methyl cellulose (HPMC) with silver nanoparticles were synthesized. They were analyzed and characterized using differential thermal analysis and thermogravimetry, atomic force microscopy, and static contact angle measurements. It was experimentally demonstrated that the silver-doped hybrid materials have pronounced antibacterial behavior by studying the reduction of Pseudomonas aeruginosa PAO1 biofilm formation on the tested materials. The results revealed biofilm reduction of 35.7% and 30% by SiO2/HPC/2.5% Ag and SiO2/HPMC/2.5% Ag hybrid materials, respectively, compared to the control. Cytotoxicity of examined materials and actin cytoskeleton organization of fibroblasts seeded on …

Mouse Osns Express 10,000 Genes, Timothy S. Mcclintock

Physiology Research Data

This Excel file (both full and compressed versions are available) contains processed GeneChip microarray data that allows predictions of whether a gene is expressed in mature olfactory sensory neurons of mice.

Coral Spawning In The Gulf Of Oman And Relationship To Latitudinal Variation In Spawning Season In The Northwest Indian Ocean, E. J. Howells, D. Abrego, G. O. Vaughan, J. A. Burt

All Works

Despite a wealth of information on sexual reproduction in scleractinian corals, there are regional gaps in reproductive records. In the Gulf of the Oman in the Arabian Sea, reproductive timing was assessed in four common species of broadcast spawning corals using field surveys of gamete maturity and aquarium observations of spawning activity. The appearance of mature gametes within the same month for Acropora downingi, A. hemprichii, Cyphastrea microphthalma and Platygyra daedalea (≥ 75% of colonies, n = 848) indicated a synchronous and multi-specific spawning season. Based on gamete disappearance and direct observations, spawning predominantly occurred during April in 2013 (75- …

The Formin Fmnl3 Assembles Plasma Membrane Protrusions That Participate In Cell–Cell Adhesion, Timothy J. Gauvin, Lorna E. Young, Henry N. Higgs

Dartmouth Scholarship

FMNL3 is a vertebrate-specific formin protein previously shown to play a role in angiogenesis and cell migration. Here we define the cellular localization of endogenous FMNL3, the dynamics of GFP-tagged FMNL3 during cell migration, and the effects of FMNL3 suppression in mammalian culture cells. The majority of FMNL3 localizes in a punctate pattern, with >95% of these puncta being indistinguishable from the plasma membrane by fluorescence microscopy. A small number of dynamic cytoplasmic FMNL3 patches also exist, which enrich near cell–cell contact sites and fuse with the plasma membrane at these sites. These cytoplasmic puncta appear to be part of …

Conformational Regulation Of Membrane Localization And Activation Of Talin, Pallavi Dwivedi

ETD Archive

Talin is a cytosolic protein which is known to be one of the key players involved in integrin mediated cell adhesion dependent processes, including blood coagulation, and tissue remodeling. It connects the extracellular matrix with the actin cytoskeleton. Talin comprises of a head domain (talin-H) and a rod domain (talin-R). Talin-H is further subdivided in F0, F1, F2 and F3 domains. Talin-R contains 13 contiguous helical bundle domains (R1-R13) followed by an actin binding dimerization domain (DD). The F3 domain contains a key integrin binding site that regulates integrin activation. In our previous studies, we have shown that cytosolic talin …

Global Approaches To The Role Of Mirnas In Drug-Induced Changes In Gene Expression, Jodi E. Eipper-Mains, Betty A. Eipper, Richard E. Mains

UCHC Articles - Research

Neurons modulate gene expression with subcellular precision through excitation-coupled local protein synthesis, a process that is regulated in part through the involvement of microRNAs (miRNAs), a class of small non-coding RNAs. The biosynthesis of miRNAs is reviewed, with special emphasis on miRNA families, the subcellular localization of specific miRNAs in neurons, and their potential roles in the response to drugs of abuse. For over a decade, DNA microarrays have dominated genome-wide gene expression studies, revealing widespread effects of drug exposure on neuronal gene expression. We review a number of recent studies that explore the emerging role of miRNAs in the …

Analysis Of Band 4.1b In Integrin-Mediated Cell Adhesion And Signaling, Youngsin Jung

Dissertations and Theses (Open Access)

Band 4.1B is a cytoskeletal adaptor protein that regulates various cellular behavior; however, the mechanisms by which Band 4.1B contributes to intracellular signaling are unclear. This project addresses in vivo and in vitro functions for Band 4.1B in integrin-mediated cell adhesion and signaling. Band 4.1B has been shown to bind to β8 integrin, although cooperative functions of these two proteins have not been determined. Here, functional links between β8 integrin and Band 4.1B were investigated using gene knockout strategies. Ablation of β8 integrin and Band 4.1B genes resulted in impaired cardiac morphogenesis, leading to embryonic lethality by E11.5. These embryos …

Gene Synthesis, Cloning, Expression, Purification And Biophysical Characterization Of The C2 Domain Of Human Tensin, Kiran Sukumar Gajula

Doctoral Dissertations

Tensin is a large "docking" protein found in the adhesive junctions of animal cells and recruited early in the development of cell-substrate contacts. There it binds to the cytoplasmic domain of integrin β1 and caps the barbed ends of filamentous actin. This forms a rational basis for its implication in a direct role in the mechanics of membrane-cytoskeleton interactions. Tensin provides a physical link between the actin cytoskeleton, integrins, and other proteins at the cell-substrate contacts. Its overall biochemical properties are a function of its domain composition and architecture, i.e., the domains that are present and their relative positions in …

Biophysical Study Of The Sh2 Domain Of Human Tensin, Yogesh Mohan Kulkarni

Doctoral Dissertations

Cell migration is a key characteristic of embryogenesis, inflammation, wound healing, tumor cell metastasis and a broad range of other normal and pathological processes. Accumulating evidence suggests that the protein tensin provides a physical link between transmembrane receptors, proteins commonly associated with signal transduction, and the actin cytoskeleton. Adhesion involves three broad classes of macromolecules: ExtraCellular Matrix (ECM) molecules, transmembrane adhesion receptors, and intracellular adhesion plaque proteins. Tensin is particularly enriched in Fibrillar Adhesions (FA's), though it is also present to a modest extent in Focal Contacts (FC's). Src Homology 2 (SH2) domains function in the transmission of molecular signals …

The Role Of Protein Synthesis On The Adhesionstrength Of Chl Cells, Ali Yildirim, William Jd Whish

Turkish Journal of Biology

Cells require protein synthesis to perform the adhesion function properly. In order to dis-cover the effect of endogenous protein synthesis on CHL cell adhesion; the adhesion strengths of cul-tured Chinese Hamster Lung (CHL) cells that were grown for 24 hours on the glass surface in the pres-ence of 1µgml -1 of cycloheximide or emetine or, both were measured quantitatively using a converg-ing laminar flow chamber. The inhibition of protein synthesis by above drug(s) reduced cell adhesion strength significantly. Hence critical shear stress of detachment of cell were 8.68±1.52 Nm -2 , 8.13±1.48Nm -2 , and 6.57±1.01Nm -2 , respectively. While …