Cell Biology Commons^™

K847a Mutation And Anionic Lipid-Presence Modify Opa1 Enzyme Kinetics And Function, J. Rafael Tolentino, Kate Walsh, Andrew D. Kehr

Annual Student Research Poster Session

Opa1 is a dynamin superfamily protein that is responsible for the fusion of the mitochondrial membrane. However, nobody knows the specific chemical mechanisms of how it interacts with lipids. Our research focuses on investigating how Opa1 interacts with lipids. In other words, we want to figure out which amino acids are crucial for Opa1's ability to bind with lipids. In hopes of understanding how Opa1 mutations affect neurodegenerative diseases, such as dominant optic atrophy.

Er Stress Tolerance Is Regulated By Copper-Dependent Perk Kinase Activity., Sarah E. Bond Newton, Xinglong Shi, Noah R. Beratan, Julia Perhacs, Jitendra K. Arya, Margaret K. Bond, Tali Gidalevitz, Cagla Akay-Espinoza, Donita C. Brady, Kelly L. Jordan-Sciutto

Farber Institute for Neuroscience Faculty Papers

Pancreatic/PKR-like endoplasmic reticulum (ER) kinase (PERK) is a kinase that, in response to ER stress, mediates dual homeostatic and pro-apoptotic signaling. Thus, intricate regulation is required for physiological function. Attempts to modulate PERK activity have shown that the determinants of adaptive vs. maladaptive signaling remain ambiguous. Here, with purified protein, we provide evidence that PERK binds copper, identifies residues required for interaction, and demonstrates that copper is necessary for kinase activity. Furthermore, cellular PERK activity can be modulated via copper availability, and this regulatory relationship can be manipulated to dictate ER stress tolerance. Critically, these phenomena translate to phenotypes in …

Editorial: Molecular Mechanisms Of Ion Channel Activation And Modulation, Meng Cui, Miao Zhang

Pharmacy Faculty Articles and Research

"Ion channels are integral membrane proteins that regulate the passage of ions across cell membranes, thereby shaping processes as diverse as neuronal signaling, muscle contraction, and hormone secretion. Channel activation is typically initiated by a stimulus such as voltage, ligand binding, or mechanical stress that induces conformational changes and opens the channel pore. Beyond activation, channels are subject to fine-tuned modulation by a wide range of endogenous and exogenous agents, from lipids and neurotransmitters to pharmacological drugs. Modulators can stabilize the open, closed, or inactivated states, shift ligand affinities, or alter gating kinetics. Dissecting the structural and dynamic basis of …

The Chromosome Complement Of Male Chrysoperla Rufilabris (Burmeister, 1839), With Evidence Of Distance Segregation In Meiosis I, Valoria G. Maslin, Allison M. Eisenhauer, Leocadia V. Paliulis

Faculty Journal Articles

Neuropteran insects display a phenomenon called distance segregation during male meiosis I, where the X and Y chromosomes are unconnected from prometaphase I through anaphase I. Here we investigate chromosome number and patterns of chromosome segregation of a previously unstudied Neuropteran: the green lacewing, Chrysoperla rufilabris (Burmeister, 1839). Testes of male C. rufilabris were isolated and prepared following a chromosome squash method. Living meiosis I spermatocytes were also imaged. The data revealed a chromosome number of 2n=12 in males (2n=10+XY) and evidence of distance segregation of X and Y chromosomes in meiosis I spermatocytes.

Retinal Precursor Cell Enriched Multiomic And Pseudo-Time Analysis Of Developing And Reprogrammed Photoreceptors, Brendon M. Patierno

Dissertations, Theses, and Capstone Projects

The vertebrate retina is a complex tissue made up of seven major cell subtypes which during development must differentiate and localize into a highly organized structure. These neuronal cells do not regenerate if damaged or diseased, and the progressive deterioration of cone photoreceptor cells is the leading cause of age related blindness. Currently there are no cures for this disease, but one promising therapeutic avenue is cell transplantation research. If we can further elucidate the gene regulatory networks that define cone cell development, this knowledge could be applied to the generation of healthy cone cells in clinically relevant models.

The …

The Sonic Hedgehog Effector Smoothened Modulates Cholinergic Interneuron Activity, Physiology, And Striatum-Dependent Behaviors, Santiago Uribe-Cano

Dissertations, Theses, and Capstone Projects

The striatum is a central node in action selection and associative learning, integrating cortical, thalamic, and neuromodulatory input. Among its principal modulators, dopamine (DA) and acetylcholine (ACh) are known for their temporally coordinated yet mechanistically distinct influences on striatal output. However, the upstream signals that regulate their dynamic interplay, particularly within cholinergic interneurons (CINs)—the primary source of striatal ACh—remain incompletely characterized. This dissertation investigates the role of Smoothened (Smo), a G protein-coupled receptor (GPCR) effector of Sonic Hedgehog (Shh) signaling, in modulating ACh signaling dynamics in the striatum.

Building on evidence that midbrain DA neurons co-release Shh and that CINs …

Mechanistic Insights Into The Neuroprotective Effects Of The Antidepressant Agomelatine In Alzheimer's Disease, Grace Terry

Dissertations, Theses, and Capstone Projects

Alzheimer’s Disease (AD) is a complex neurodegenerative disease that has limited treatment options and no cure. AD is characterized by robust pathology including extracellular amyloid beta plaques, intracellular neurofibrillary tangles, neuronal and synaptic loss, neuroinflammation, and brain atrophy. AD presents with cognitive decline and memory loss but only years after neuropathology has started to accumulate. This robust pathology has made AD difficult to treat and highlights the need for therapeutics that modulate multiple pathways. Agomelatine (AGO) was selected by a high-throughput machine learning drug repurposing algorithm by our collaborator Dr. Lie Xie (Hunter College Dept. of Comp. Sci.) as having …

Bmp Signaling Co-Regulation Of Immune Response And Lipid Metabolism, Katerina K. Yamamoto

Dissertations, Theses, and Capstone Projects

The Bone Morphogenetic Proteins (BMPs) are secreted peptide ligands of the Transforming Growth Factor beta (TGF-β) family, initially identified for their roles in development and differentiation across animal species. They are now increasingly recognized for their roles in physiology and infectious disease. In the nematode Caenorhabditis elegans, the BMP ligand DBL-1 controls fat metabolism and immune response, in addition to its roles in body size regulation and development. DBL-1 regulates classical aspects of innate immunity, including the induction of anti-microbial peptides. We theorized that BMP-dependent regulation of fat metabolism could also promote resilience against microbial pathogens. We found that …

Investigating The Role Of Early Growth Response 1 (Egr1) Gene In Riluzole-Induced Apoptosis In Osteosarcoma, Syeda Maryam Azeem

Dissertations, Theses, and Capstone Projects

Osteosarcoma is a rare but aggressive bone malignancy most commonly affecting adolescents and young adults (AYA). With 5-year survival rate stagnating over the last four decades despite the advancements in multi-modal therapy, drug repurposing offers a rapid path to new osteosarcoma treatments. Recent studies suggest that Riluzole, a drug approved for amyotrophic lateral sclerosis (ALS), may be repurposed for osteosarcoma treatment due to its ability to slow tumor progression and induce apoptosis. Previously, we have shown that Riluzole increases reactive oxygen species (ROS), activating c-Abl, which phosphorylates YAP in the nucleus. YAP then forms a complex with p73 to enhance …

Centrosomal And Non-Centrosomal Microtubule Networks Coordinate To Drive Nuclear Dynamics In Developing Epithelium, Rashmi Budhathoki

Electronic Theses and Dissertations

The morphogenesis of developing tissues relies on extensive cellular rearrangements in shape, position, and identity. A key process in reshaping tissues is cell intercalation-driven elongation, where epithelial cells align and intercalate along a common axis. Typically, analyses focus on how peripheral cortical forces influence cell shape changes. Less attention is given to how inhomogeneities in internal structures, particularly the nucleus, impact cell shaping. Here, we examine how pulsed contractile and extension dynamics interact with the nucleus in elongating Drosophila embryos. Our data show that tightly packed nuclei in apical layers hinder tissue remodeling/oscillatory behaviors. We identify two mechanisms for resolving …

Kinase Suppressor Of Ras 2 Regulates Energy Balance And Tumor Initiation, Dianna H. Huisman

Theses & Dissertations

Kinase Suppressor of Ras 2 (KSR2) is a scaffold that facilitates Raf-MEK-ERK signaling and is expressed in the brain, pituitary, and adrenal gland. Here, we demonstrate that KSR2 functions in the adult brain to maintain organismal energy balance and in small-cell lung carcinoma (SCLC) to promote self-renewal and clonogenicity. Disruption of KSR2 in adult mice results in hyperphagia, obesity, reduced metabolic rate, and altered activity. Using spatial transcriptomics, we identify regions of the brain associated with regulation of feeding and energy expenditure with altered gene expression following KSR2 disruption. These findings reveal regions of interest in which targeted KSR2 disruption …

Protocol For Vibratome Sectioning, Immunofluorescence, And S-Phase Labeling Of Inner Ear Organoids, Jiayi Wu, Stefan Heller, Maggie S. Matern

Biology Faculty Publications

Inner ear organoids represent a potentially inexhaustible source of otic tissues, including sensory hair cells and supporting cells, for in vitro manipulation. Here, we present a protocol for labeling S-phase entry of cells in inner ear organoids using 5-ethynyl-2′-deoxyuridine (EdU), followed by fixation and vibratome sectioning. Nuclear EdU is then detected alongside protein markers of interest via immunofluorescence. This workflow enables the visualization of cell and tissue morphologies within developing organoids and assessment of how different manipulations affect cell proliferation.

Development Of Emerin Mrna Lipid Nanoparticles To Rescue Myogenic Differentiation., Nicholas Marano, Liza Elif Guner, Rachel S Riley, James M Holaska

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Emery-Dreifuss muscular dystrophy 1 (EDMD1) arises from mutations in EMD. Most EDMD1 patients lack detectable emerin expression. They experience symptoms such as skeletal muscle wasting, joint contractures, and cardiac conduction defects. Currently, physicians rely on treating patient symptoms without addressing the underlying cause-lack of functional emerin protein. Thus, there is a need for therapeutic approaches that restore emerin protein expression to improve patient outcomes. One way would be to deliver emerin mRNA or protein directly to affected tissues to restore tissue homeostasis. Here, we evaluated the utility of lipid nanoparticles (LNPs) to deliver emerin mRNA to diseased cells. LNPs …

Global Erk/Mapk Activation Determines Oncogenic Fitness In Kras-Mutant Pancreatic Ductal Adenocarcinoma, Rachel A. Burge

MUSC Theses and Dissertations

In pancreatic ductal adenocarcinoma (PDAC), ~95% of cases harbor an activating KRAS mutation. The most common KRAS mutations in PDAC are KRAS^G12D (42%), KRAS^G12V (31%), and KRAS^G12R (15%). Patients harboring KRAS^G12R mutations have increased overall survival compared to those with KRAS^G12D/V-mutations. While KRAS^G12D/Vare common in all KRAS-mutant cancers, KRAS^G12Ris only common in PDAC.

KRAS^G12R is unable to activate the lipid kinase PIK3CA, a KRAS effector that is important for tumorigenesis in murine models. To investigate the tumorigenic potential of KRAS^G12R and the mechanisms that enable this mutation …

Effect Of Moderate Decrease In Contractility On Epithelial Cell-Cell Contacts Under External Stretch, Saika Sharmin

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial tissues are characterized by extensive cell–cell contacts and often subject to stretch during normal function. Cell-cell contact adhesion strength maintains mechanical continuity from cell to cell. Mechanical forces exerted by cells via actomyosin contractility are known to strengthen cell-cell adhesions to a certain extent. While it is known that a large decrease in contractility causes cell-cell contact rupture due to weakened adhesions, it is unclear how a moderate reduction in contractility affects cell-cell junction stability. Here, we studied how a moderate inhibition of non-muscle myosin II (NMII) affects the integrity of epithelial cell-cell contacts, especially when subject to the …

Advanced Interactions Of Directed Energy With Retinal Pigment Epithelial Cells And Their Photochemical And Photothermal Responses, Jin B. Ha

Theses & Dissertations

Excess optical radiation can injure the retina through either rapid heat deposition (photothermal damage) or cumulative photo‑oxidative stress (photochemical damage), yet current laser‑safety limits treat these mechanisms as independent. To test that assumption, this dissertation integrated systematic wavelength, duration and temperature‑controlled laser exposures with live/dead fluorescence imaging in a melanin‑loaded hTERT‑RPE1 monolayer model. First, concurrent 447 nm (blue) and 2 µm (infra‑red) beams delivered for 200 s demonstrated a strong thermal–photochemical synergy: each beam alone was sub‑threshold (≤25 % lethality) but together produced 100 % RPE death without exceeding 50 °C, proving that modest heating markedly lowers the photon dose …

Assessing The Impact Of Pll And Ple Concentrations And Aging On Protein Condensates Formation Via Llps, Nabil Harche

Theses, Dissertations and Culminating Projects

Protein droplets, also referred to as condensates, are membrane-less organelles formed through a biophysical process known as liquid-liquid phase separation (LLPS). These structures play an indispensable role in a wide range of cellular functions, including compartmentalizing biochemical reactions, regulating gene expression, and responding to cellular stress. Unlike traditional membrane-bound organelles, these condensates form dynamically and reversibly within the cytoplasm or nucleus, without the need for lipid membranes. The formation of these protein droplets is affected by several physicochemical factors, including pH, temperature, ionic strength, concentration of biomolecules, and specific molecular interactions such as electrostatics and hydrophobic forces. LLPS results in …

Crevice Corrosion Mechanisms Of Cocrmo Alloys In Orthopedic Implants: Retrieval Analysis, Nano-Tribocorrosion And Cellular Responses, Hwaran Lee

All Dissertations

Mechanically assisted corrosion and non-mechanically (chemically) driven corrosion in modular junctions of orthopedic implants using cobalt-chromium-molybdenum (CoCrMo) alloys remain clinical concerns and may contribute to implant failure. The underlying corrosion mechanisms are not yet fully understood, leaving a critical research gap. We hypothesized that corrosion in modular junctions may be driven by aggressive local environments, including fretting, metal ion release (cobalt ion, Co²⁺), low pH and reactive oxygen species (ROS). This dissertation aims to (1) analyze corrosion modes and potential causes in modular junctions; (2) identify chemically driven corrosion modes on CoCrMo alloys using simulated inflammatory modular taper …

The Role Of Cleavage And Polyadenylation Spcific Factor 6 (Cpsf6) In Hematopoiesis, Fengxi Ye

Dissertations and Theses (Open Access)

Cleavage and polyadenylation specific factor 6 (Cpsf6) translocation is frequently reported in APLL, which is Acute Promyelocytic Leukemia (APL)-like acute myeloid leukemia (AML) and other types of blood diseases associated with abnormal hematopoiesis. CPSF6 is a subunit of the Cleavage Factor I mammalian (CFIm) complex, which regulates post-transcriptional alternative polyadenylation (APA) of pre-mRNAs. Previous research indicated that Cpsf6 plays an essential role in alternative polyadenylation, development, and tumorigenesis. However, the role of Cpsf6 in hematopoiesis is unknown. Given its roles in APA, development and cancer, we hypothesize that Cpsf6 plays a critical role in hematopoiesis and that its …

Impact Of S-Phase Kinase Protien 2 Blockades On Hematopoetic Stem Cell Metabolism, Nicole Elmaraghy

Electronic Theses, Projects, and Dissertations

Hematopoietic stem and progenitor cells (HSPCs) quiescence is vital for the success of bone marrow transplantation, as it preserves long term self- renewal and prevents premature exhaustion (Takubo et al., 2013; Wilson et al., 2008). However, bone marrow transplant (BMT) failure remains a clinical challenge, often due to lack of long-term engraftment and insufficient stress reliance. Both of these characteristics are tightly linked to disrupted stem cell quiescence and metabolic imbalance (Anso et al., 2017; Vannini et al., 2016). One key player is S-phase kinase protein (SKP2), an E3 ubiquitin ligase that targets cell cycle inhibitors, like p27, for proteosome …