Biochemistry, Biophysics, and Structural Biology Commons^™

Protein-Protein Interactions In Cell Cycle Proteins: An In Silico Investigation Of Two Important Players, Andriele Eichner

Dissertations, Theses, and Capstone Projects

The examination of the cell cycle carries significant implications for the biology, health, and overall existence of all living things. These implications span from the development and growth of these organisms to the aging process and cancer, as well as the potential of stem cell therapies to repair diseases and injuries. Numerous proteins of the cell cycle are essential for cellular division and proliferation and are widely conserved over the course of evolution. In this work, we aimed to investigate the molecular processes of protein-protein interactions in cell cycle proteins, centering on two key players: Cdc6 in budding yeast and …

Characterizing The Multifaceted Roles Of The Proteasomal Deubiquitinase Uch37 In Proteostasis, Heather A. Bisbee

Doctoral Dissertations

Cellular protein pools are maintained through the biological processes of synthesis, degradation and quality control. As the dysregulation of these processes has been implicated in diseases such as neurodegeneration and cancer, understanding their functions is critical for drug development. Modification of proteins with ubiquitin may direct them to the proteasome, a large cellular protease complex, for degradation. Yet, the proteasome contains three deubiquitinating enzymes (DUBs) which remove ubiquitin from proteins, potentially altering their fate. As each DUB recognizes specific ubiquitin linkages and architectures, their activity may regulate how the proteasome handles substrates in dynamic cellular contexts. In this work, we …

Characterization Of The Wee1 Homologues And The Investigation Of Factors Promoting Cellular Enlargement In Cryptococcus Neoformans, Rodney J. Colón Reyes

All Dissertations

Cryptococcus neoformans is an opportunistic fungal pathogen, infecting mainly immunocompromised individuals. As the main cause of cryptococcosis, it is responsible for over 180,000 deaths every year. As an environmental yeast, it has unique adaptations that allow it to proliferate in the human host. Among these adaptations its capacity to transition to an extreme phenotype known as Titan cells is of special interest to researchers. With sizes above 10 um and able to reach 70 um or more in cell size. This size is accompanied with a large vacuole, larger polysaccharide capsule, and an increased resistance to fluconazole (FLC). FLC is …

The Role Of Isothiocyanates As Cancer Chemo‐Preventive, Chemo‐Therapeutic And Anti‐Melanoma Agents, Melina Mitsiogianni, Georgios Koutsidis, Nikos Mavroudis, Dimitrios T. Trafalis, Sotiris Botaitis, Rodrigo Franco, Vasilis Zoumpourlis, Tom Amery, Alex Galanis, Aglaia Pappa, Mihalis I. Panayiotidis

School of Veterinary and Biomedical Sciences: Faculty Publications

Many studies have shown evidence in support of the beneficial effects of phytochemicals in preventing chronic diseases, including cancer. Among such phytochemicals, sulphur‐containing compounds (e.g., isothiocyanates (ITCs)) have raised scientific interest by exerting unique chemopreventive properties against cancer pathogenesis. ITCs are the major biologically active compounds capable of mediating the anticancer effect of cruciferous vegetables. Recently, many studies have shown that a higher intake of cruciferous vegetables is associated with reduced risk of developing various forms of cancers primarily due to a plurality of effects, including (i) metabolic activation and detoxification, (ii) inflammation, (iii) angiogenesis, (iv) metastasis and (v) regulation …

Novel Docosahexaenoic Acid Ester Of Phloridzin Inhibits Proliferation And Triggers Apoptosis In An In Vitro Model Of Skin Cancer, Theodora Mantso, Dimitrios T. Trafalis, Sotiris Botaitis, Rodrigo Franco, Aglaia Pappa, H. P. Vasantha Rupasinghe, Mihalis I. Panayiotidis

School of Veterinary and Biomedical Sciences: Faculty Publications

Skin cancer is among the most common cancer types accompanied by rapidly increasing incidence rates, thus making the development of more efficient therapeutic approaches a necessity. Recent studies have revealed the potential role of decosahexaenoic acid ester of phloridzin (PZDHA) in suppressing proliferation of liver, breast, and blood cancer cell lines. In the present study, we investigated the cytotoxic potential of PZDHA in an in vitro model of skin cancer consisting of melanoma (A375), epidermoid carcinoma (A431), and non-tumorigenic (HaCaT) cell lines. Decosahexaenoic acid ester of phloridzin led to increased cytotoxicity in all cell lines as revealed by cell viability …

Interaction Between Atm Kinase And P53 In Determining Glioma Radiosensitivity, Syed F. Ahmad

Theses and Dissertations

Glioblastoma multiforme (GBM) is the most common primary brain tumor. Studies have shown that targeting the DNA damage response can sensitize cancer cells to DNA damaging agents. Ataxia telangiectasia mutated (ATM) is involved in signaling DNA double strand breaks. Our group has previously shown that ATM inhibitors (ATMi) sensitize GBM cells and tumors to ionizing radiation. This effect is greater when the tumor suppressor p53 is mutated.

The goals of this work include validation of a new ATM inhibitor, AZ32, and elucidation of how ATMi and p53 status interact to promote cell death after radiation. We propose that ATMi and …

Transcriptional Regulation Of Sinorhizobium Meliloti Cell Cycle-Related Genes In The Δcbra Mutant And Root Nodules Of Medicago Sativa, Corey S. Hazekamp

Graduate Masters Theses

Sinorhizobium meliloti is a Gram-negative alphaproteobacterium and nitrogen-fixing symbiont, which undergoes a novel cell cycle modification during its' host-microbe interaction. I intend to monitor the transcriptional regulation of cell cycle-related genes during free-loving growth, in addition to monitoring their expression during symbiosis. Using genes known to be regulated by CtrA in C. crescentus or predicted to be regulated by CtrA in S. meliloti, I aim to show how certain cell cycle genes are regulated in S. meliloti. In C. crescentus, CtrA acts as a transcription factor that is active when phosphorylated and inactive when not phosphorylated. In …

Characterizing The Role Of The Retinoblastoma Protein Lxcxe Binding Cleft In Cellular Senescence And Tumor Suppression, Srikanth Talluri

Electronic Thesis and Dissertation Repository

The Retinoblastoma protein (pRB) is a key regulator of the cell cycle and is functionally inactivated in most cancers. pRB has been proposed to utilize simultaneous interactions with E2F transcription factors and chromatin regulatory proteins to repress transcription and block cell cycle progression. The goal of this study is to characterize the physiological role of pRB interactions with chromatin regulatory proteins. I used gene targeted mice carrying point mutations in the murine Rb1 gene (Rb1^∆L) that specifically disrupt pRB’s LXCXE binding cleft, and thereby its ability to interact with chromatin regulatory proteins while leaving its ability to …

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 …

Nanosecond Pulsed Electric Field Effects On Cell Cycle And Apoptosis, Emily H. Hall

Theses and Dissertations in Biomedical Sciences

Apoptosis, programmed cell death, is a highly regulated and complex pathway essential for embryonic development, immune-system function and maintenance of tissue homeostasis where cells induce their own cell death. Cells undergoing apoptosis exhibit a distinctive phenotype characterized by maintenance of membrane integrity, cell shrinkage, phosphatidylserine (PS) externalization at the plasma membrane, caspase protease activation, DNA fragmentation, release of cytochrome c from the mitochondrion, and membrane blebbing. An important regulatory protein in the apoptotic pathway is p53. The p53 protein functions to modulate the cell cycle by arresting cells in the G1 and G 2 phases to repair DNA damage, and/or …