Cell Biology Commons^™

Molecular Mechanisms Underlying Migratory And Immune-Evasion Properties Of Circulating Tumor Cells, Jeannette A. Huaman

Dissertations, Theses, and Capstone Projects

Metastasis is the leading cause of cancer deaths worldwide. However, there exist only limited treatment options and they are often ineffective. An important aspect of metastasis that requires study, but has previously been understudied is circulating tumor cells (CTCs). CTCs are a critical step in the metastatic cascade. They can be analyzed for the identification of key mechanisms in metastasis. To this end, we isolated CTCs from a syngeneic mouse model of hepatocellular carcinoma (HCC) and a human xenograft mouse model of castration-resistant prostate cancer (CRPC). From these mouse models, primary tumor and CTC lines were established. Functional characterization of …

Lps, A Tlr-4 Agonist And Viper A Tlr-4 Inhibitor Upregulate Phagocytosis Of Zymosan In Bv2 Cells, Sherouk Alzeory

Dissertations and Theses

Microglia cells are the first line of innate immunity defense in the central nervous system (CNS). They play a critical role in maintaining CNS homeostasis by having an active but yet balanced phagocytic activity. However, in various CNS related diseases, microglia cells have been shown to malfunction. In Alzheimer's Disease (AD), hyperactive microglia with impaired phagocytic activity is the main hallmark of this disease, along with the accumulation of amyloid-beta aggregates. Additionally, emerging new studies have suggested a fungal infection etiology to AD, specifically in relation to Candida albicans (C.albicans). Thus, understanding the mechanism of fungal clearance in the …

Analysis Of Adult Neural Retina Extracellular Vesicle Release, Rna Transport And Proteomic Cargo, Jason Mighty, Jing Zhou, Alberto Benito-Martin, Sami Sauma, Samer Hanna, Onyekwere Onwumere, Cui Shi, Martin Muntzel, Moira Sauane, Michael Young, Henrik Molina, Dianne Cox, Stephen Redenti

Publications and Research

PURPOSE. Extracellular vesicles (EVs) contain RNA and protein cargo reflective of the genotype and phenotype of the releasing cell of origin. Adult neural retina EV release, RNA transfer, and proteomic cargo are the focus of this study.

METHODS. Adult wild-type mouse retinae were cultured and released EV diameters and concentrations quantified using Nanosight. Immunogold transmission electron microscopy (TEM) was used to image EV ultrastructure and marker protein localization. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze retinal cell transcripts present in EVs. Super-resolution microscopy was used to image fluorescent (green) RNA and (red) lipid membrane labeled EVs, released …

Hyaluronan At The Brain-Environment Interface, Donald M. Thevalingam

Dissertations, Theses, and Capstone Projects

Hyaluronan (HA; Hyaluronic Acid), a primary scaffolding component of the brain extracellular matrix, serves as an integral structural component to the brain extracellular space (ECS). The fossorial African naked mole-rat (Heterocephalus glaber; NM-R), a mammal which lives in a low-oxygen environment and is capable of tolerating hypoxia and hypercapnia, has been shown to synthesize and sustain a unique high-molecular-mass variant of hyaluronan macromolecule (HMM-HA). This body of work highlights HA’s role in mediating the interplay between brain ECM composition, ECS structure, and cell viability.

Here we employ the NM-R as a unique animal model to observe the role of the …

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …

Anti-Cancer Effects Of Oleocanthal And Extra Virgin Olive Oil, Limor Goren

Dissertations, Theses, and Capstone Projects

Oleocanthal is a phenolic compound found in varying concentrations in extra virgin olive oil. Oleocanthal has been shown to be active physiologically, benefiting several diseased states by conferring anti-inflammatory and neuroprotective benefits. Recently, we and other groups have demonstrated its specific and selective toxicity toward cancer cells; however, the mechanism leading to cancer cell death is still disputed. The current study demonstrates that oleocanthal induced damage to cancer cells’ lysosomes leading to cellular toxicity in vitro. Non-cancer cells were significantly less affected. Lysosomal membrane permeabilization following oleocanthal treatment in various cell lines was assayed via three complementary methods. Additionally, …

Inhibition Of Mitochondrial Permeability Transition By Deletion Of The Ant Family And Cypd, Jason Karch, Michael J. Bround, Hadi Khalil, Michelle A. Sargent, Nadina Latchman, Naohiro Terada, Pablo M. Peixoto, Jeffery D. Molkentin

Publications and Research

The mitochondrial permeability transition pore (MPTP) has resisted molecular identification. The original model of the MPTP that proposed the adenine nucleotide translocator (ANT) as the inner membrane pore-forming component was challenged when mitochondria from Ant1/2 double null mouse liver still had MPTP activity. Because mice express three Ant genes, we reinvestigated whether the ANTs comprise the MPTP. Liver mitochondria from Ant1, Ant2, and Ant4 deficient mice were highly refractory to Ca2+-induced MPTP formation, and when also given cyclosporine A (CsA), the MPTP was completely inhibited. Moreover, liver mitochondria from mice with quadruple deletion of Ant1, Ant2, Ant4, and Ppif (cyclophilin …

Histology Atlas: Basic Mammalian Tissue Types (Biol 105), Joshua Barnes, Daniel J. Yakubov, Corinna Singleman, Nathalia G. Holtzman

Open Educational Resources

This book is a guide to the basic histology lab conducted as a part of the Queens College, CUNY Biology Department Bio105 General Biology: Physiology and Cell Biology course. This course is the first half our two-part series for biology majors. The actives are designed to be conducted over a single 3-hour lab periods which focus on the relationship of form and function of the cellular and organ level anatomy and physiology. Step by step instructions for each slide set are provided for all the key organs.

In addition to the full text of the book, we also provide a …

Fetal Pig Dissection Manual (Biol 105), Nathalia G. Holtzman, Daniel J. Yakubov

Open Educational Resources

This book is a guide to the basic fetal pig dissection conducted as a part of the Queens College, CUNY Biology Department Bio105 General Biology: Physiology and Cell Biology course. This course is the first half our two-part series for biology majors. The actives are designed to be conducted over a three- 3-hour lab periods which focus on the relationship of form and function of the pig anatomy and physiology. Step by step instructions for the dissection are provided along with some microscopy tasks to look at the histology of key organs.

In addition to the full text of the …

The 5-Ht1a-R Knockout Mouse As A Model Of Later Life Anxiety Disorders: Implications For Sex Differences, Tatyana Budylin

Dissertations, Theses, and Capstone Projects

Anxiety affects nearly twice as many women as it affects men across all cultures and economic groups. Importantly, girls have a higher chance of inheriting anxiety disorders than boys, and many anxiety disorders appear at a very young age. However, little is known about sex differences in brain and behavioral development and how they relate to anxiety in adulthood. Serotonin 1A receptor (5-HT_1A-R) mediated signaling has been implicated in depression and anxiety, however most studies that focus on the involvement of the 5-HT_1A-R have been conducted in adults. Little is known about how the 5-HT_{1A …}

The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy

Dissertations, Theses, and Capstone Projects

Cellular homeostasis is achieved by the dynamic flux in gene expression. Post-transcriptional regulation of coding and non-coding RNA offers a fast method of adapting to a changing cellular environment, including deadenylation, microRNA (miRNA) pathway, and alternative polyadenylation (APA). In this dissertation, I explored some of the mechanisms involved in the post-transcriptional regulation of gene expression. The main hypothesis in these studies is that a single APA event after DNA damage is governed by specific conditions and factors outside of current known regulators of APA, and that the resultant transcript has a role in the DNA damage response (DDR). My aims …

Human Anatomy And Physiology I: Course Map With Expected Learning Outcomes, Carlos Liachovitzky

Open Educational Resources

This document contains a list with all the Anatomy and Physiology I expected learning outcomes organized by topics, and grouped into ten units: 1. Introduction to A&P: body plan & organization; 2. Introduction to A&P: homeostasis; 3. The chemical level of organization; 4. Levels of organization: the cellular level of organization; 5. Levels of organization: the tissue level of organization; 6. Support and movement: integumentary system; 7. Support and movement: skeletal system & articulations; 8. Support and movement: muscular system; 9. Regulation, integration, and control: nervous system; 10. Regulation, integration, and control: special senses

Each learning outcome is referred to …

A Novel Kinesin Adapter Directly Mediates Dendritic Mrna Localization During Synapse Development, Hao Wu

Dissertations, Theses, and Capstone Projects

Cytoskeleton based active transport with motor proteins is essential for mRNA localization and local protein translation in animal cells, yet how mRNA granules interact with motor proteins remains poorly understood. Using an unbiased screen for interaction between mRNA binding proteins (RBP) and motor proteins, we identified protein interacting with APP tail 1 (PAT1) as a potential direct adapter between the β-actin mRNA Zipcode-binding protein 1 (ZBP1) and Kinesin-1 motor complex.

Mouse PAT1 is similar to the Kinesin Light Chain (KLC) in amino acid sequence and binds directly to KLC. High-resolution images from structured illumination microscopy (SIM) indicates that synaptic stimulation …

The Molecular Mechanisms Underlying The Cancer Killing Effect Of Interleukin-24, Leah Eshanie Persaud

Dissertations, Theses, and Capstone Projects

Interleukin-24 (IL-24) is an immunomodulatory cytokine that also displays specific anti-tumor effects across many cancer cell types. The tumor suppressor activities of IL-24 include inhibition of angiogenesis, metastasis, toxic autophagy, cancer-specific apoptosis, and sensitization to traditional cancer treatments like chemotherapy and radiation. Overexpression of IL-24 can selectively induce apoptosis in various cancer cells while having no adverse effects on normal cells. Due to this favorable killing effect, IL-24 is currently in phase II clinical trials. There is accumulating evidence that IL-24’s anti-cancer activity is primarily through the endoplasmic reticulum (ER) stress pathway but other pathways leading to cell death are …

Tryptophan Confers Resistance To Sds-Associated Cell Membrane Stress In Saccharomyces Cerevisiae, Lea Schroeder, Amy E. Ikui

Publications and Research

Sodium dodecyl sulfate is a detergent that disrupts cell membranes, activates cell wall integrity signaling and restricts cell growth in Saccharomyces cerevisiae. However, the underlying mechanism of how sodium dodecyl sulfate inhibits cell growth is not fully understood. Previously, we have shown that deletion of the MCK1 gene leads to sensitivity to sodium dodecyl sulfate; thus, we implemented a suppressor gene screening revealing that the overexpression of TAT2 tryptophan permease rescues cell growth in sodium dodecyl sulfatetreated Δmck1 cells. Therefore, we questioned the involvement of tryptophan in the response to sodium dodecyl sulfate treatment. In this work, we show that …

Advances In Geometric Techniques For Analyzing Blebbing In Chemotaxing Dictyostelium Cells, Zully Santiago, John Loustau, David Meretzky, Devarshi Rawal, Derrick Brazill

Publications and Research

We present a technical platform that allows us to monitor and measure cortex and membrane dynamics during bleb-based chemotaxis. Using D. discoideum cells expressing LifeAct-GFP and crawling under agarose containing RITC-dextran, we were able to simultaneously visualize the actin cortex and the cell membrane throughout bleb formation. Using these images, we then applied edge detect to generate points on the cell boundary with coordinates in a coordinate plane. Then we fitted these points to a curve with known x and y coordinate functions. The result was to parameterize the cell outline. With the parameterization, we demonstrate how to compute data …

Deletion Of Mgr2p Affects The Gating Behavior Of The Tim23 Complex, Oygul Mirzalieva, Shinhye Jeon, Kevin Damri, Ruth Hartke, Layla Drwesh, Keren Demishtein-Zohary, Abdussalam Azem, Cory D. Dunn, Pablo M. Peixoto

Publications and Research

The TIM23 complex is a hub for translocation of preproteins into or across the mitochondrial inner membrane. This dual sorting mechanism is currently being investigated, and in yeast appears to be regulated by a recently discovered subunit, the Mgr2 protein. Deletion of Mgr2p has been found to delay protein translocation into the matrix and accumulation in the inner membrane. This result and other findings suggested that Mgr2p controls the lateral release of inner membrane proteins harboring a stop-transfer signal that follows an N-terminal amino acid signal. However, the mechanism of lateral release is unknown. Here, we used patch clamp electrophysiology …

Characterizing Chromosomal Aberrations In Cells Deficient For Both Atm And Msh2, Yeliz Inalman

Dissertations and Theses

Ataxia telangiectasia mutated (ATM) and mutS homologue 2 (MSH2) are important DNA repair proteins that participate in DNA repair pathways to maintain genomic integrity. Mice deficient for ATM and MSH2 mice are viable. However, ATM^-/- mice show growth retardation, neurological defects, and spontaneous lymphomagenesis. MSH2^-/- mice suffer from aggressive lymphoid tumors between two to five months of age and have increased microsatellite instability, which predisposes MSH2^-/- mice to carcinomas. However, mice deficient in both ATM and MSH2 are unable to survive beyond postnatal day 21 (P21). The observed lethality in ATM^-/-MSH2^-/- mice may result …

Sonic Hedgehog Is Expressed By Hilar Mossy Cells And Regulates Cellular Survival And Neurogenesis In The Adult Hippocampus, Luis E. Gonzalez-Reyes, Chia-Chu Chiang, Mingming Zhang, Joshua Johnson, Manuel Arrillaga-Tamez, Nicholas H. Couturier, Neha Reddy, Lev Starikov, Jeffrey R. Capadona, Andreas H. Kottmann, Dominique M. Durand

Publications and Research

Sonic hedgehog (Shh) is a multifunctional signaling protein governing pattern formation, proliferation and cell survival during embryogenesis. In the adult brain, Shh has neurotrophic function and is implicated in hippocampal neurogenesis but the cellular source of Shh in the hippocampus remains ill defined. Here, we utilize a gene expression tracer allele of Shh (Shh-nlacZ) which allowed the identification of a subpopulation of hilar neurons known as mossy cells (MCs) as a prominent and dynamic source of Shh within the dentate gyrus. AAV-Cre mediated ablation of Shh in the adult dentate gyrus led to a marked degeneration …

Investigating The Impact Of Oxidative Stress On Tetrahymena Thermophila Sirtuin,Thd 18, Emmanuel Dubuisson

Publications and Research

Sirtuins are a family of enzymes that fulfill various important biological functions. Investigators have looked for the implication of Sirtuin genes in cell signaling mechanisms, in the formation and silencing of heterochromatin, in the regulation of ion channels, and in the modulation of the cellular redox reactions[2]. Different model organisms have been previously used to conduct these studies; among them, there are yeasts, nematodes, and fruit flies. Each one has made some valuable contribution into the vast body of knowledge related to this field.

However, gaps in the understanding of Sirtuins functions still remain to be filled. In this optic, …

Pyronaridine Exerts Potent Cytotoxicity On Human Breast And Hematological Cancer Cells Through Induction Of Apoptosis, Paulina J. Villanueva, Alberto Martinez, Sarah T. Baca, Rebecca E. Dejesus, Manuel Larragoity, Lisett Contreras, Denisse A. Gutierrez, Armando Varela-Ramirez, Renato J. Aguilera

Publications and Research

The potent antimalarial drug pyronaridine (PND) was tested for its potential as an anticancer drug. After exposing cancerous (17) and non-cancerous (2) cells to PND for 72 hr, PND was found to exhibit consistent and potent cytotoxic activity at low micromolar (μM) concentrations that ranged from 1.6 μM to 9.4 μM. Moreover, PND exerted a significant selective cytotoxicity index (SCI) on five out of seven breast cancer cell lines tested, with favorable values of 2.5 to 4.4, as compared with the non-cancerous breast MCF-10A cell line. By using the same comparison, PND exhibited a significant SCI on three out of …

Mechanisms Adopted By Dengue-2 Viruses To Induce Autophagy In Mammalian Cells, Sounak Ghosh Roy

Dissertations, Theses, and Capstone Projects

Dengue, the most rapidly spreading flavivirus, threatens to affect almost half of the human global population. We previously showed that dengue-2 protects canine kidney cells (MDCK) from cytotoxic chemicals. We showed, independently, that cell protection, as well as viral replication and maturation, are positively regulated by PI3K-dependent autophagy. However, we had not identified the specific pathway that induces autophagy in infected cells. The current study explores the role of a specific branch of the endoplasmic reticulum (ER) stress-mediated Unfolded Protein Response (UPR), the PERK/eIF2α/ATF4 pathway in the induction of autophagy by …

Renal Risk Variants Of Apolipoprotein L-1 Form Channels At The Plasma Membrane That Lead To A Cytotoxic Influx Of Calcium, Joseph A. Giovinazzo

Dissertations, Theses, and Capstone Projects

Apolipoprotein L-1 (APOL1) is a secreted protein that provides protection against several protozoan parasites due to its channel forming properties. Recently evolved variants, G1 and G2, increase kidney disease risk when present in two copies. In mammalian cells, overexpression of G1 and G2, but not wild-type G0, leads to swelling and eventual lysis. However, the mechanism of cell death remains elusive with multiple pathways being invoked, such as autophagic cell death mediated by a BH3 domain in APOL1, which we evaluated in this study. We hypothesized that the common trigger for these pathways is the APOL1 cation channel, which is …

Lim Protein Ajuba Associates With The Rpa Complex Through Direct Cell Cycle-Dependent Interaction With The Rpa70 Subunit, Sandy Fowler, Pascal Maguin, Sampada Kalan, Diego Loayza

Publications and Research

DNA damage response pathways are essential for genome stability and cell survival. Specifically, the ATR kinase is activated by DNA replication stress. An early event in this activation is the recruitment and phosphorylation of RPA, a single stranded DNA binding complex composed of three subunits, RPA70, RPA32 and RPA14. We have previously shown that the LIM protein Ajuba associates with RPA, and that depletion of Ajuba leads to potent activation of ATR. In this study, we provide evidence that the Ajuba-RPA interaction occurs through direct protein contact with RPA70, and that their association is cell cycle-regulated and is reduced upon …

Δ-9-Thc Effect On The Dopamine Transporter, Brooke E. Nielsen

Student Theses

Understanding the mechanism behind drugs of abuse is one of the key elements to understanding why addiction is so prevalent in society. The goal of this research was to determine the effect that a popular cannabinoid, Δ -9-tetrahydrocannabinol has on the regulation of dopamine neurotransmitter in the synapses. It was hypothesized that the addictive high users experience from using Δ-9-THC had a direct effect on lowering the dopamine transporter protein on cell surface causing a buildup of dopamine in the synapse. The results of the study show that the higher concentration of Δ-9-THC that the cells were exposed to caused …

Antioxidants And Cancer: Theories, Techniques, And Trials In Preventing Cancer, Gloria M. Calaf, Francisco Aguayo, Consolato M. Sergi, Angeles Juarranz, Debasish Roy

Publications and Research

No abstract provided.

Regulation Of The Tubulin Homolog Ftsz In Escherichia Coli, Monika S. Buczek

Dissertations, Theses, and Capstone Projects

Escherichia coli is a well-known pathogen, and importantly, a widely used model organism in all fields of biological sciences for cloning, protein purification, and as a model for Gram-negative bacterial species. And yet, researchers do not fully understand how this bacterium replicates and divides. Every year additional division proteins are discovered, which adds complexity to how we understand E. coli undergoes cell division. Due to their specific roles in cytokinesis, some of these proteins may be potential targets for development of antibacterials or bacteriostatics, which are much needed for fighting the current global antibacterial deficit. My thesis work focuses on …

Mechanisms For Survival And Drug Resistance In Cancer Cells, Matthew B. Utter

Dissertations, Theses, and Capstone Projects

PART I

Prostate cells are hormonally driven to grow and divide. Typical treatments for prostate cancer involve blocking the hormone androgen from activating the androgen receptor (AR) and thus inhibit growth and proliferation of the cancer. Androgen deprivation therapy (ADT) can lead to the selection of cancer cells that grow and divide independently of androgen receptor activation. Prostate cancer cells that are insensitive to androgens commonly display metastatic phenotypes and reduced long-term survival of patients. In this study, we provide evidence that androgen-insensitive prostate cancer cells have elevated phospholipase D (PLD) activity relative to the androgen-sensitive prostate cancer cells. PLD …

The Role Of Mdm2 In Dna Damage Signaling, Stanley Tam

Theses and Dissertations

The overexpression of the oncogene MDM2 is common in a variety of human cancers. MDM2 overexpression is known to increase genome instability in cells by delaying DNA double strand break repair and γH2AX levels. This study explores the knockdown of MDM2 and how it may affect DNA damage signaling.

Zero Textbook Cost Syllabus For Bio 3005 (Molecular And Cellular Biology), Krista Dobi, Kim Macklin

Open Educational Resources

The biology of cells is examined with an emphasis on the relationship between organelle structure and function. Activity of the nucleus, cell structure, division and growth, and tools for studying genes will be discussed. Laboratory experiments are performed with isolated organelles or intact cells. Techniques include cell fractionation, bio-chemical assays, and DNA isolation and modification. Students will also read and analyze articles from scientific journals.