Cell Biology Commons^™

Identification Of New Cell Size Control Genes In S. Cerevisiae, Huzefa Dungrawala, Hui Hua, Jill Wright, Lesley Abraham, Thivakorn Kasemsri, Anthony Mcdowell, Jessica Stilwell, Brandt L. Schneider

Molecular Biosciences Faculty Publications

Cell size homeostasis is a conserved attribute in many eukaryotic species involving a tight regulation between the processes of growth and proliferation. In budding yeast S. cerevisiae, growth to a “critical cell size” must be achieved before a cell can progress past START and commit to cell division. Numerous studies have shown that progression past START is actively regulated by cell size control genes, many of which have implications in cell cycle control and cancer. Two initial screens identified genes that strongly modulate cell size in yeast. Since a second generation yeast gene knockout collection has been generated, we screened …

The Two-Component Signal Transduction System Arlrs Regulates Staphylococcus Epidermidis Biofilm Formation In An Ica-Dependent Manner, Yang Wu, Jiaxue Wang, Tao Xu, Jingran Liu, Wenqi Yu, Qiang Lou, Tao Zhu, Nianan He, Haijing Ben, Jian Hu, Friedrich Götz, Di Qu

Molecular Biosciences Faculty Publications

Due to its ability to form biofilms on medical devices, Staphylococcus epidermidis has emerged as a major pathogen of nosocomial infections. In this study, we investigated the role of the two-component signal transduction system ArlRS in regulating S. epidermidis biofilm formation. An ArlRS-deficient mutant, WW06, was constructed using S. epidermidis strain 1457 as a parental strain. Although the growth curve of WW06 was similar to that of SE1457, the mutant strain was unable to form biofilms in vitro. In a rabbit subcutaneous infection model, sterile disks made of polymeric materials were implanted subcutaneously followed with inoculation of WW06 or SE1457. …

Wipi-1 Positive Autophagosome-Like Vesicles Entrap Pathogenic Staphylococcus Aureus For Lysosomal Degradation, Mario Mauthe, Wenqi Yu, Oleg Krut, Martin Krönke, Friedrich Götz, Horst Robenek, Tassula Proikas-Cezanne

Molecular Biosciences Faculty Publications

Invading pathogens provoke the autophagic machinery and, in a process termed xenophagy, the host cell survives because autophagy is employed as a safeguard for pathogens that escaped phagosomes. However, some pathogens can manipulate the autophagic pathway and replicate within the niche of generated autophagosome-like vesicles. By automated fluorescence-based high content analyses, we demonstrate that Staphylococcus aureus strains (USA300, HG001, SA113) stimulate autophagy and become entrapped in intracellular PtdIns(3)P-enriched vesicles that are decorated with human WIPI-1, an essential PtdIns(3)P effector of canonical autophagy and membrane protein of both phagophores and autophagosomes. Further, agr-positive S. aureus (USA300, HG001) strains were more efficiently …

One-Pot Regioselective Synthesis Of Tetrahydroindazolones And Evaluation Of Their Anti-Proliferative And Src Kinase Inhibitory Activities, V. Kameshwara Rao, Bhupender S. Chhikara, Rakesh Tiwari, Amir Nasrolahi Shirazi, Keykavous Parang, Anil Kumar

Pharmacy Faculty Articles and Research

A number of 2-substituted tetrahydroindazolones were synthesized by three-component condensation reaction of 1,3- diketones, substituted hydrazines, benzaldehydes, and Yb(OTf)3 as a catalyst in [bmim][BF4] ionic liquid using a simple, efficient, and economical one-pot method. The synthesized tetrahydroindazolones were evaluated for inhibition of cell proliferation of human colon carcinoma (HT-29), human ovarian adenocarcinoma (SK-OV-3), and c-Src kinase activity. 3,4-Dichlorophenyl tetrahydroindazolone derivative (15) inhibited the cell proliferation of HT-29 and SK-OV-3 cells by 62% and 58%, respectively. 2,3-Diphenylsubstituted tetrahydroindazolone derivatives, 19, 25, and 33, inhibited the cell proliferation of HT-29 cells by 6572% at a concentration of 50 μM. In general, the …

A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel

CMC Senior Theses

The field of stem cell research has been growing more because of the interest in using stem cells to cure diseases and heal injuries. Human embryonic stem cells, because of the controversy surrounding them—and subsequently the difficulties in acquiring samples of the existing aging cell lines—can only be used in limited capacities. While the development of induced pluripotent stem cells in the last decade has allowed the field to progress closer to medical treatments, the low efficiency of reprogramming a somatic cell to a pluripotent state, and the vast molecular and genomic differences between human embryonic stem cells and human …

Melatonin Membrane Receptors In Peripheral Tissues: Distribution And Functions, Radomir M. Slominski, Russel J. Reiter, Natalia Schlabritz-Loutsevich, Rennolds S. Ostrom, Andrzej T. Slominski

Pharmacy Faculty Articles and Research

Many of melatonin’s actions are mediated through interaction with the G-protein coupled membrane bound melatonin receptors type 1 and type 2 (MT1 and MT2, respectively) or, indirectly with nuclear orphan receptors from the RORα/RZR family. Melatonin also binds to the quinone reductase II enzyme, previously defined the MT3 receptor. Melatonin receptors are widely distributed in the body; herein we summarize their expression and actions in non-neural tissues. Several controversies still exist regarding, for example, whether melatonin binds the RORα/RZR family. Studies of the peripheral distribution of melatonin receptors are important since they are attractive targets for immunomodulation, regulation of endocrine, …

A Preliminary Study On The Potential Of Manuka Honey And Platelet-Rich Plasma In Wound Healing, Scott A. Sell, Patricia S. Wolfe, Andrew J. Spence, Isaac A. Rodriguez, Jennifer M. Mccoll, Rebecca L. Petrella, Koyal Garg, Jeffery J. Ericksen, Gary L. Bowlin

Ellmer School of Nursing Faculty Publications

Aim. The purpose of this study was to determine the in vitro response of cells critical to the wound healing process in culture media supplemented with a lyophilized preparation rich in growth factors (PRGF) and Manuka honey. Materials and Methods. This study utilized cell culture media supplemented with PRGF, as well as whole Manuka honey and the medical-grade Medihoney (MH), a Manuka honey product. The response of human fibroblasts (hDF), macrophages, and endothelial cells (hPMEC) was evaluated, with respect to cell proliferation, chemotaxis, collagen matrix production, and angiogenic potential, when subjected to culture with media containing PRGF, MH, Manuka honey, …

Lenalidomide Targets The T-Cell Co-Stimulatory Pathway To Mediate Immune Modulation, Jessica Marie Mcdaniel

USF Tampa Graduate Theses and Dissertations

T-cells are lymphocytes that make up part of the adaptive arm of the immune system, and are essential for efficient protection from and eradication of viruses and pathogens. T-cells not only play an important role in protection from external agents, but also regulate and prevent activation towards self-peptides and detect and remove erratically growing cells. Alterations in T-cell activation and suppression contribute to auto-immunity, immunocompromised disorders, and cancer progression.

The immune system, and T-cells in particular, provides daily surveillance, recognition and destruction of aberrant cells. Although the immune system is proficient at suppressing malignant progression, tumor cells acquire various methods …

Hyperosmotic Stress Enzyme Signaling Modulates Oct4, Nanog, And Rex1 Expression And Induces Prioritized Differentiation Of Murine Embryonic Stem Cells, Jill A. Slater

Wayne State University Dissertations

HYPEROSMOTIC STRESS ENZYME SIGNALING MODULATES OCT4, NANOG,

AND REX1 EXPRESSION AND INDUCES PRIORITIZED DIFFERENTIATION OF

MURINE EMBRYONIC STEM CELLS

by

JILL SLATER

MAY 2013

Advisor: Daniel Rappolee, Ph.D.

Major: Physiology

Degree: Doctor of Philosophy

Transcription factor expression and therefore lineage identity in the periimplantation

embryo and its stem cells may be influenced by extracellular stresses,

potentially affecting pregnancy outcome. Cellular stress forces cells to suppress some

normal activities (such as protein synthesis and cell proliferation) in order to repair

stress-damaged macromolecules and restore homeostasis. Therefore, any new

activities that embryonic cells initiate while concurrently funding the demands of the

stress …

Effects Of Binge Alcohol Exposure On Canonical Wnt Signaling During Fracture Repair, Kristen Leigh Lauing

Dissertations

Excessive alcohol consumption is associated with increased fracture risk, delayed bone healing and fracture non-union. Binge alcohol consumption has occurred in 25-40% of all orthopaedic trauma cases. The canonical Wnt pathway, through tight regulation of stabilized beta-catenin, plays an essential and pivotal role in the formation of new bone and cartilage to initiate bone repair. We sought to determine the molecular mechanisms behind alcohol-related fracture complications by testing the hypothesis that binge alcohol exposure deregulates canonical Wnt signaling in the fracture callus, leading to impaired healing.

To test this, C57BL/6 or beta-catenin/TCF-reporter male mice were exposed to intraperitoneal alcohol or …

The Role Of Nucleotide Excision Repair In Restoring Replication Following Uv-Induced Damage In Escherichia Coli, Kelley Nicole Newton

Dissertations and Theses

Following low levels of UV exposure, Escherichia coli cells deficient in nucleotide excision repair recover and synthesize DNA at near wild type levels, an observation that formed the basis of the post replication recombination repair model. In this study, we characterized the DNA synthesis that occurs following UV-irradiation in the absence of nucleotide excision repair and show that although this synthesis resumes at near wild type levels, it is coincident with a high degree of cell death. We confirm that the replication occurring under these conditions involves extensive levels of strand exchange. However, cells undergoing this form of replication accumulate …

Choreographing The Adenylyl Cyclase Signalosome: Sorting Out The Partners And The Steps, Rennolds S. Ostrom, Amy S. Bogard, Robert Gros

Pharmacy Faculty Articles and Research

Adenylyl cyclases are a ubiquitous family of enzymes and are critical regulators of metabolic and cardiovascular function. Multiple isoforms of the enzyme are expressed in a range of tissues. However, for many processes, the adenylyl cyclase isoforms have been thought of as essentially interchangeable, with their impact more dependent on their common actions to increase intracellular cyclic adenosine monophosphate content regardless of the isoform involved. It has long been appreciated that each subfamily of isoforms demonstrate a specific pattern of “upstream” regulation, i.e., specific patterns of ion dependence (e.g., calcium-dependence) and specific patterns of regulation by kinases (protein kinase A …

Higher Il-6 And Il6:Igf Ratio In Patients With Barth Syndrome, Lori D. Wilson, Sadeeka Al-Majid, Cyril Rakovski, Christina D. Schwindt

Mathematics, Physics, and Computer Science Faculty Articles and Research

Background: Barth Syndrome (BTHS) is a serious X-linked genetic disorder associated with mutations in the tafazzin gene (TAZ, also called G4.5). The multi-system disorder is primarily characterized by the following pathologies: cardiac and skeletal myopathies, neutropenia, growth delay, and exercise intolerance. Although growth anomalies have been widely reported in BTHS, there is a paucity of research on the role of inflammation and the potential link to alterations in growth factors levels in BTHS patients.

Methods: Plasma from 36 subjects, 22 patients with Barth Syndrome (0.5 - 24 yrs) and 14 healthy control males (8 - 21 yrs) was …

In Vitro Study Of The Microsporidian Parasite Loma Morhua, Using Cod-Derived Cells And Novel Culture Techniques, Michael J. Macleod

Theses and Dissertations (Comprehensive)

The cod populations of the Canadian Atlantic were once highly productive, generating enormous annual harvests and attracting fishing fleets from many nations. However, through the late 1980s improved fishing technology, unprecedented capture rates, and poor fishery management brought wild stocks beyond the point of collapse. Dwindling harvests in the early 1990s resulted in cod fishing moratoriums, and an end to the productivity for which the fishery was once renowned. Atlantic cod remains a popular food worldwide and the collapse of cod fisheries has done little to abate market demands. Consequently, the cod is considered a prime candidate for aquaculture production, …

A Mathematical Model For Cell Cycle-Specific Cancer Virotherapy, Joanna R. Wares, Joseph J. Crivelli, Juraj Földes, Peter S. Kim

Department of Math & Statistics Faculty Publications

Oncolytic viruses preferentially infect and replicate in cancerous cells, leading to elimination of tumour populations, while sparing most healthy cells. Here, we study the cell cycle-specific activity of viruses such as vesicular stomatitis virus (VSV). In spite of its capacity as a robust cytolytic agent,VSVcannot effectively attack certain tumour cell types during the quiescent, or resting, phase of the cell cycle. In an effort to understand the interplay between the time course of the cell cycle and the specificity of VSV, we develop a mathematical model for cycle-specific virus therapeutics. We incorporate the minimum biologically required time spent in the …

Toward A Functional Characterization Of The Acidic-Domain Of The Chloroplast Protein Import Receptor Toc159, Joseph K. Weston

Theses and Dissertations (Comprehensive)

Chloroplasts are members of a diverse class of organelles called plastids that differentiate plants from other eukaryotes, and are the site of a number of essential biochemical pathways including photosynthesis. Nuclear-encoded pre-proteins, which account for ~95% of chloroplast proteins, are post-translationally imported into plastids across the double envelope membrane. In the model plant Arabidopsis thaliana, the majority of pre-proteins are imported via the Toc (translocon at outer envelope membrane of chloroplasts) and Tic (translocon at inner envelope membrane of chloroplasts) complexes, the key components of which have been identified. The Toc159 …

Electric Field Exposure Triggers And Guides Formation Of Pseudopod-Like Blebs In U937 Monocytes, Mikhail A. Rassokhin, Andrei G. Pakhomov

Bioelectrics Publications

We describe a new phenomenon of anodotropic pseudopod-like blebbing in U937 cells stimulated by nanosecond pulsed electric field (nsPEF). In contrast to "regular," round-shaped blebs, which are often seen in response to cell damage, pseudopod-like blebs (PLBs) formed as longitudinal membrane protrusions toward anode. PLB length could exceed the cell diameter in 2 min of exposure to 60-ns, 10-kV/cm pulses delivered at 10-20 Hz. Both PLBs and round-shaped nsPEF-induced blebs could be efficiently inhibited by partial isosmotic replacement of bath NaCl for a larger solute (sucrose), thereby pointing to the colloid-osmotic water uptake as the principal driving force for bleb …

Inefficient Replication Reduces Reca-Mediated Repair Of Uvdamaged Plasmids Introduced Into Competent Escherichia Coli, Harout Arthur Jeiranian, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

Transformation of Escherichia coli with purified plasmids containing DNA damage is frequently used as a tool to characterize repair pathways that operate on chromosomes. In this study, we used an assay that allowed us to quantify plasmid survival and to compare how efficiently various repair pathways operate on plasmid DNA introduced into cells relative to their efficiency on chromosomal DNA. We observed distinct differences between the mechanisms operating on the transforming plasmid DNA and the chromosome. An average of one UV-induced lesion was sufficient to inactivate ColE1-based plasmids introduced into nucleotide excision repair mutants, suggesting an essential role for repair …

Uvrd Participation In Nucleotide Excision Repair Is Required For The Recovery Of Dna Synthesis Following Uv-Induced Damage In Escherichia Coli, Kelley Nicole Newton, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

UvrD is a DNA helicase that participates in nucleotide excision repair and several replication-associated processes, including methyl-directed mismatch repair and recombination. UvrD is capable of displacing oligonucleotides from synthetic forked DNA structures in vitro and is essential for viability in the absence of Rep, a helicase associated with processing replication forks. These observations have led others to propose that UvrD may promote fork regression and facilitate resetting of the replication fork following arrest. However, the molecular activity of UvrD at replication forks in vivo has not been directly examined. In this study, we characterized the role UvrD has in processing …

Protein Folding By 'Levels Of Separation': A Hypothesis, Lesley H. Greene, Terri M. Grant

Chemistry & Biochemistry Faculty Publications

The protein folding process has been studied both computationally and experimentally for over 30 years. To date there is no detailed mechanism to explain the formation of long-range interactions between the transition and native states. Long-range interactions are the principle determinants of the tertiary structure. We present a theoretical model which proposes a mechanism for the acquisition of these interactions as they form in a modified version of ‘degrees of separation’, that we term ‘levels of separation’. It is based on the integration of network science and biochemistry. (C) 2012 Federation of European Biochemical Societies.