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Why Should Early-Career Scientists Publish In Society Journals, Stephen K. Dolan, Lori D. Banks, Wenqi Yu

Molecular Biosciences Faculty Publications

In this editorial, written by early-career scientists, we advocate for the invaluable role of society journals in our scientific community. By choosing to support these journals as authors, peer reviewers, and as editors, we can reinforce our academic growth and benefit from their re-investment back into the scientific ecosystem. Considering the numerous clear merits of this system for future generations of microbiologists and more broadly, society, we argue that early-career researchers should publish our high-quality research in society journals to shape the future of science and scientific publishing landscape.

The Inaugural Mbio Junior Editorial Board—Lessons Learned And The Path Forward Toward Improving The Peer Review Process, Cynthia Ayefoumi Adinortey, Stephen K. Dolan, Sarah Doore, Rebeccah Lijek, Diana Priscila Pires, Wenqi Yu, Elizabeth B. Draganova, Lennart Schada Von Borzyskowski

Molecular Biosciences Faculty Publications

The inaugural Junior Editorial Board (JEB) of mBio consisted of 64 early-career researchers active from 2022 to 2023. The goal of the JEB was to train early-career researchers in the art of peer review under the guidance of experienced editors. JEB members gained hands-on experience in peer review by participating in modules detailing the publishing process through the lenses of the journal, editor, and reviewer. Ultimately, JEB members applied this new knowledge by reviewing mBio manuscripts. Here, we summarize the background, the mission, and the achievements of the first mBio JEB. We also include possible trajectories for the future editions …

Targeting Bet Proteins Downregulates Mir-33a To Promote Synergy With Pim Inhibitors In Cmml, Christopher T. Letson

USF Tampa Graduate Theses and Dissertations

Chronic Myelomonocytic Leukemia (CMML) is a rare myeloid malignancy with a dismal prognosis and no therapeutic options which are capable of altering the natural course of the disease. There remains a significant need for novel therapies that are able to meaningfully improve patient outcomes. In this study we explore the effectiveness of Bromodomain and Extra-Terminal domain protein inhibitor (BETi) combinations in CMML. Preclinical studies in myeloid neoplasms have demonstrated efficacy of BETi. However, BETi demonstrate poor single agent activity in clinical trials. Several studies suggest that combinations with other anti-cancer inhibitors may enhance the efficacy of BETi. To nominate BETi …

Thermodynamic Frustration Of Tad2 And Prr Contribute To Autoinhibition Of P53, Emily Gregory

USF Tampa Graduate Theses and Dissertations

The intrinsically disordered transcription factor and tumor suppressor p53 binds to promoter response element DNA upon cellular stress and activates genes associated with cell cycle arrest, senescence, and apoptosis. Disruption of sequence specific binding to target gene promoters is heavily implicated in human health, where a majority of cancers contain mutations localized to the DNA binding domain (DBD) of p53. p53 DNA binding is regulated by posttranslational modifications, associations with cellular factors, and by an autoinhibitory intramolecular interaction. The autoinhibitory intramolecular interaction occurs when the disordered N-terminal transactivation domain (TAD) interacts with the ordered DBD. Previous work in the Daughdrill …

Withaferin A And Immune Checkpoint Blocker Therapy For The Treatment Of Non-Small Cell Lung Cancer, Roukiah Khalil

USF Tampa Graduate Theses and Dissertations

Lung cancer is the first cause of cancer-related deaths in both men and women with an overall five-year survival rate of 28%. Although immune checkpoint blockers (ICBs) are currently FDA-approved for the treatment of non-small cell lung cancer (NSCLC), only 17-20% of patients achieve durable responses by the induction of immunologic memory. The lack of response in most patients can be attributed to the tumor-intrinsic or tumor-extrinsic immune resistance mechanisms. A biomarker of importance is the Programmed Death Ligand-1 (PD-L1), as higher PD-L1 expression is usually associated with a better response to ICBs. Although studies have attempted to combine ICBs …

Exploring Strain Variation And Bacteriophage Predation In The Gut Microbiome Of Ciona Robusta, Celine Grace F. Atkinson

USF Tampa Graduate Theses and Dissertations

Current microbiome studies have shown that the maintenance of homeostasis betweenmicrobial populations (e.g. bacteria, viruses) and the host immune system (e.g. innate immune molecules) is necessary for balancing health and disease outcomes within the host. These studies most often utilize vertebrate models; however, research in this field can benefit from diverse model systems that facilitate our ability to conduct experiments to identify phylogenically conserved rules influencing homeostasis in the gut of animals. The Dishaw has developed the use of a filter-feeding marine invertebrate chordate, Ciona robusta, to model such fundamental interactions[1]–[6]. While most biological diversity and functional contribution within microbiomes …

A Novel Role For Enos In Regulating Lymphatic Valve Development During Embryogenesis, Drishya Iyer

USF Tampa Graduate Theses and Dissertations

Lymphedema is a disease that occurs when lymph flow is impaired, resulting in tissue swelling, fibrosis, chronic inflammation and recurrent secondary infections. Lymphatic valves play a critical role in maintaining unidirectional lymph flow and evidence for valve defects have been reported in lymphedema patients. The lack of drugs that can correct lymphatic valve defects warrants a better understanding of the molecular regulators of lymphatic valve development and maintenance. Lymphatic valves first develop during embryogenesis in response to mechanotransduction signaling pathways triggered by oscillatory lymph flow. Since eNOS (gene name: Nos3) is a well characterized mechanotransduction signaling molecule in blood vessels, …

Otud5 Limits Replication Fork Instability By Organizing Chromatin Remodelers, Angelo De Vivo, Hongseon Song, Yujin Lee, Neysha Tirado-Class, Anthony Sanchez, Sandy D. Westerheide, Huzefa Dungrawala, Younghoon Kee

Molecular Biosciences Faculty Publications

Proper regulation of replication fork progression is important for genomic maintenance. Subverting the transcription-induced conflicts is crucial in preserving the integrity of replication forks. Various chromatin remodelers, such as histone chaperone and histone deacetylases are known to modulate replication stress, but how these factors are organized or collaborate are not well understood. Here we found a new role of the OTUD5 deubiquitinase in limiting replication stress. We found that OTUD5 is recruited to replication forks, and its depletion causes replication fork stress. Through its C-terminal disordered tail, OTUD5 assembles a complex containing FACT, HDAC1 and HDAC2 at replication forks. A …

The Identification Of Two M20b Family Peptidases Required For Full Virulence In Staphylococcus Aureus, Nathanial James Torres, Devon Rizzo, Maria A. Reinberg, Mary-Elizabeth Jobson, Brendan C. Totzke, Jessica K. Jackson, Wenqi Yu, Lindsey Neil Shaw

Molecular Biosciences Faculty Publications

We have previously demonstrated that deletion of an intracellular leucine aminopeptidase results in attenuated virulence of S. aureus. Herein we explore the role of 10 other aminopeptidases in S. aureus pathogenesis. Using a human blood survival assay we identified mutations in two enzymes from the M20B family (PepT1 and PepT2) as having markedly decreased survival compared to the parent. We further reveal that pepT1, pepT2 and pepT1/2 mutant strains are impaired in their ability to resist phagocytosis by, and engender survival within, human macrophages. Using a co-infection model of murine sepsis, we demonstrate impairment of dissemination and survival …

Dcaf14 Regulates Cdt2 To Promote Set8-Dependent Replication Fork Protection, Neysha Tirado-Class, Caitlin Hathaway, Anthony Nelligan, Huzefa Dungrawala

Molecular Biosciences Faculty Publications

DDB1- and CUL4-associated factors (DCAFs) CDT2 and DCAF14 are substrate receptors for Cullin4–RING E3 ubiquitin ligase (CRL4) complexes. CDT2 is responsible for PCNA-coupled proteolysis of substrates CDT1, p21, and SET8 during S-phase of cell cycle. DCAF14 functions at stalled replication forks to promote genome stability, but the mechanism is unknown. We find that DCAF14 mediates replication fork protection by regulating CRL4CDT2 activity. Absence of DCAF14 causes increased proteasomal degradation of CDT2 substrates. When forks are challenged with replication stress, increased CDT2 function causes stalled fork collapse and impairs fork recovery in DCAF14-deficient conditions. We further show that stalled fork protection …

X-Linked Ubiquitin-Specific Peptidase 11 Increases Tauopathy Vulnerability In Women, Yan Yan

USF Tampa Graduate Theses and Dissertations

Women experience significantly higher tau burden and increased risk for Alzheimer’s disease (AD) than men, yet the underlying mechanism for this vulnerability has not been explained. Here, we demonstrate through in vitro and in vivo models, as well as human AD brain tissue, that X-linked ubiquitin specific peptidase 11 (USP11) augments pathological tau aggregation via tau deubiquitination initiated at lysine-281. Removal of ubiquitin provides access for enzymatic tau acetylation at lysines 281 and 274. USP11 escapes complete X-inactivation, and female mice and people both exhibit higher USP11 levels than males. Genetic elimination of usp11 in a tauopathy mouse model preferentially …

Regulation Of The Heat Shock Response Via Lysine Acetyltransferase Cbp-1 And In Neurodegenerative Disease In Caenorhabditis Elegans, Lindsey N. Barrett

USF Tampa Graduate Theses and Dissertations

The decline of proteostasis is a hallmark of aging that is, in part, affected by the dysregulation of the heat shock response (HSR), a highly conserved cellular response to proteotoxic stress in the cell. The heat shock transcription factor HSF-1 is well-studied as a key regulator of proteostasis, but mechanisms that could be used to modulate HSF-1 function to enhance proteostasis during aging are largely unknown. In this study, we examined lysine acetyltransferase regulation of the HSR and HSF-1 in C. elegans. We performed an RNA interference screen of lysine acetyltransferases and examined mRNA expression of the heat-shock inducible gene …

A Protein-Based Therapeutic Combination For The Treatment Of Hard-To-Heal Wounds, Graham L. Strauss

USF Tampa Graduate Theses and Dissertations

Chronic wounds present many clinical challenges in relation to the successful treatment and closure of the damaged tissue. Most current treatment methods focused on one or two aspects to drive wound closure, while most chronic wounds are multifactorial environments with many of those dependencies relying on the termination of one another to effectively gain tissue construction, closure, and full skin thickness and composition. Natural wound healing processes allude to potential biologics that can impede the chronic breakdown of tissue, while restoring deposition of new tissue, and effectively leading to a healed wound. Proteases secreted by the body’s immune system lay …

The Role Of Eicosanoid Metabolism In Mammalian Wound Healing And Inflammation, Kenneth D. Maus

USF Tampa Graduate Theses and Dissertations

Inflammatory wounds, both chronic and acute, lead to increased morbidity and mortality rates, especially in the elderly population. The annual healthcare cost for chronic wound care alone is over $39B in the US and the demographic of susceptible patients is steadily increasing due to an aging population and lifestyle-related diseases (e.g., hyperlipidemia, obesity, and type 2 diabetes). In fact, many chronic wounds currently have a worse 5-year outlook than certain types of cancers. This shows the need for expediting the wound healing process in such a way that compresses inflammatory signaling and encourages wound resolution without sacrificing pathogen removal and …

Role Of Bmi1 In Acute Lung Injury, María Helena Hernández-Cuervo

USF Tampa Graduate Theses and Dissertations

Acute Lung Injury (ALI) is a set of signs and symptoms that lead to acute hypoxemic respiratory failure characterized by bilateral pulmonary infiltrates not attributed to cardiogenic origin. It is caused by a massive innate immune response, with the migration of white blood cells (neutrophils and macrophages principally) and a cytokine storm, followed by alterations in mitochondrial function, increase in reactive oxygen species production, and oxidative stress that in turn induces more mitochondrial damage. Several studies have shown that mitochondrial alterations are key events in the mechanism of ALI and reducing mitochondrial dysfunction could be a possible target in the …

Sequence Properties Of An Intramolecular Interaction That Inhibits P53 Dna Binding, Emily Gregory, Gary W. Daughdrill

Molecular Biosciences Faculty Publications

An intramolecular interaction between the p53 transactivation and DNA binding domains inhibits DNA binding. To study this autoinhibition, we used a fragment of p53, referred to as ND WT, containing the N-terminal transactivation domains (TAD1 and TAD2), a proline rich region (PRR), and the DNA binding domain (DBD). We mutated acidic, nonpolar, and aromatic amino acids in TAD2 to disrupt the interaction with DBD and measured the effects on DNA binding affinity at different ionic strengths using fluorescence anisotropy. We observed a large increase in DNA binding affinity for the mutants consistent with reduced autoinhibition. The ΔΔG between DBD and …

Phip Variants Associated With Chung–Jansen Syndrome Disrupt Replication Fork Stability And Genome Integrity, Neysha Tirado-Class, Caitlin Hathaway, Wendy K. Chung, Huzefa Dungrawala

Molecular Biosciences Faculty Publications

Chung–Jansen syndrome (CJS) is a rare, autosomal dominant disorder characterized by developmental delay, intellectual disability/cognitive impairment, behavioral challenges, obesity, and dysmorphic features. CJS is associated with heterozygous variants in PHIP (Pleckstrin-Homology Interacting Protein), a gene that encodes one of several substrate receptors for Cullin4-RING (CRL4) E3 ubiquitin ligase complex. Full-length PHIP, also called DCAF14, was recently identified to function as a replication stress response protein. Herein, we report the identification of two PHIP missense variants identified by exome sequencing in unrelated individuals with CJS. The variants p.D488V and p.E963G occur in different functional elements of DCAF14-WD40 repeat domain and pleckstrin …

Unraveling The Role Of Novel G5 Peptidase Family Proteins In Virulence And Cell Envelope Biogenesis Of Staphylococcus Aureus, Stephanie M. Marroquin

USF Tampa Graduate Theses and Dissertations

Virulence factors and the bacterial cell envelope are two important components in S. aureus pathogenesis and survival. More importantly, understanding the regulation of these cellular processes is crucial to further understanding and combating this successful pathogen. To date, numerous factors have been identified as playing a role in the regulation of Agr activity in S. aureus, including transcription factors, antisense RNAs, and host elements. Herein we investigate the product of SAUSA300_1984 (termed MroQ), a transmembrane G5 peptidase family protein, as a novel effector of this system. Using a USA300 mroQ mutant we observed a drastic reduction in proteolysis, hemolysis, and …

The Role Of Cpeb2 Alternative Splicing In Tnbc Metastasis, Shaun C. Stevens

USF Tampa Graduate Theses and Dissertations

Breast cancer is the second leading cause of cancer-related deaths for women in the U.S. Although the overall 5-year survival rate for breast cancer is 90%, this rate drops substantially for triple-negative breast cancer (TNBC) due to its high metastatic potential. Furthermore, there is a lack of targeted therapeutics for TNBC, and clinical trials have been largely unsuccessful. These characteristics validate the need for identifying novel therapeutic targets for the treatment of TNBC. The study of alternative splicing (AS) has emerged as a powerful tool to elucidate the molecular underpinnings driving cancer.

Our lab has identified cytoplasmic polyadenylation element-binding protein …

Investigation Of An Alternative Protocol For The Production Of Sars-Cov-2 Antigenic Proteins, Nichole Ninaltowski

USF Tampa Graduate Theses and Dissertations

With the COVID-19 pandemic showing no signs of slowing down, large-scale antigenic protein production is still needed for surveillance using serologic assays. From screening to vaccines to biotherapeutics, being able to produce the proteins for these assays is essential; however, the current gold standard method for producing SARS-CoV-2 spike proteins is prohibitively expensive for most research groups.

Alternative methods of transfecting mammalian cells to produce recombinant proteins that are relatively inexpensive have been used for years. Unlike the expensive, commercially available lipid-based methods, other established methods such as polyethyleneimine (PEI), are considerably easier, and cheaper to meet the needs of …

Cellular And Molecular Alterations Associated With Ovarian And Renal Cancer Pathophysiology, Ravneet Kaur Chhabra

USF Tampa Graduate Theses and Dissertations

Elucidating molecular alterations underlying tumor development and chemoresistance are critical to expand our understanding of the disease pathophysiology. This dissertation is focused on analyzing the cellular and molecular alterations associated with LPA-induced chemoresistance in clear cell renal cell carcinoma (ccRCC) cells and chronic iron-induced deregulation of miRNA expression in fallopian tube secretory epithelial cells (FTSECs).

Kidney cancer is one of the ten most common cancers worldwide with <15% survival rate at advanced stage (American Cancer Society). ccRCC is the most common type of kidney cancer and is described as a metabolic disease characterized by deregulated lipid metabolism leading to increased intracellular lipid droplets [9, 10]. The current molecular-targeted treatment strategies involve VEGF/VEGFR and mTOR inhibition [9, 12]. However, there are limitations to these approaches leading to the reduced efficacy and/or increased resistance in ccRCC cells [13, 14]. Therefore, it is important to decipher the factors involved in compromising the chemosensitivity in these cells.

Lysophosphatidic acid (LPA), a bioactive phospholipid, was previously reported to increase resistance against Sunitinib (VEGFR/PDGFR inhibitor) in ccRCC cells and to increase migration and invasion in various tumors [15-17]. In Chapter 3 of …

Screening Next-Generation Fluorine-19 Probe And Preparation Of Yeast-Derived G Proteins For Gpcr Conformation And Dynamics Study, Wenjie Zhao

USF Tampa Graduate Theses and Dissertations

GPCR regulates numerous diverse physiological processes relevant to diabetes, obesity, Alzheimer's diseases, and several central nervous system disorders and targets proteins in signaling pathways. It has created nearly 200 billion profits from its derivative drugs in 2018. There are near 400 structures of over 70 GPCRs have been resolved by X-ray crystallography, cryo-electron microscopy, and NMR spectroscopy. One of the current challenges that remain in the conformational transition and dynamics study using NMR spectroscopy is to obtain sufficient quantities of the G proteins and GPCRs. Pichia pastoris has shown its tremendous promise in expressing the GPCRs in a high yield, …

Evolution Of Targeted Therapy Resistance In Eml4-Alk Positive Non-Small Cell Lung Cancer, Robert Vander Velde

USF Tampa Graduate Theses and Dissertations

Targeted therapies have emerged as potent treatments that lead to the remission of many tumors. However, they rarely cure cancers in advanced, metastatic settings. This is due to the evolution of resistance, which in turn can be ascribed to the survival of small subpopulations of tolerant and/or resistant cells. Here we investigated the evolution of resistance to EML4-ALK inhibitors in non-small cell lung cancer (NSCLC) and demonstrated that resistance evolves gradually, from unique pre-treatment sub-populations, as multiple resistance mechanisms accumulate in a Darwinian fashion. Despite accumulating multiple changes, cells evolved, in parallel, toward similar inhibitor specific phenotypes. Evolving cells have …

Transcriptomic And Functional Investigation Of Bacterial Biofilm Formation, Brooke R. Nemec

USF Tampa Graduate Theses and Dissertations

Staphylococcus aureus and Acinetobacter baumannii are two highly successful human pathogens, which have adopted very different, but effective survival strategies. The success of S. aureus is attributed to the tight regulation of an arsenal of virulence factors. Conversely, A. baumannii lacks what would be considered traditional virulence factors and, instead, has developed a high tolerance for environmental stress, which allows it to persist in unforgiving environments, including nosocomial settings and the human body. One common characteristic of these two organisms is their proclivity for biofilm formation. Herein, we discuss the diverse mechanisms governing biofilm formation for A. baumannii and S. …

Cytoplasmic Polyadenylation Element Binding Protein 2 Alternative Splicing Regulates Hif1Α During Chronic Hypoxia, Emily M. Mayo

USF Tampa Graduate Theses and Dissertations

Chronic pulmonary hypoxia commonly results in the sustained expression of HIF1 (hypoxia inducible factor 1), a heterodimeric transcription factor, that, if unrestrained, can result in dramatic vasculature remodeling, pulmonary arterial hypertension, and right-sided heart failure. Together, these pulmonary disorders cost approximately $100 billion annually to treat due to the limited therapeutic targets designed to inhibit HIF1 expression. In this study, we introduce a translational regulator of HIF1 expression, known as Cytosolic polyadenylation element binding proteins 2 (CPEB2). Our lab has previously demonstrated in cancer cells that alternatively spliced isoforms of CPEB2 regulate the translation of the HIF1 oxygen-dependent subunit, HIF1α, …

Circrev1 Expression In Triple-Negative Breast Cancer, Meagan P. Horton

USF Tampa Graduate Theses and Dissertations

Triple-negative breast cancer (TNBC) comprises only 24% of breast cancer cases, yet is the second leading cause of cancer mortality in women due to its aggressive nature (1). This increase in mortality is due to the lack of receptors for three targetable growth factors (HER2, progesterone, and estrogen receptors). Our previous studies have indicated that these cancers are highly dysregulated in respect to alternative splicing. Hence, we undertook a study aimed at identifying circular RNAs (circRNAs) generated from back-splicing events which were dysregulated in TNBC. We have identified a novel circRNA transcript, circular REV1 (circREV1), which is upregulated in our …

Bone Microenvironmental Control Of Skeletal Malignancy, Chen Hao Lo

USF Tampa Graduate Theses and Dissertations

Bone is a common site of metastasis for many solid malignancies. Bone-metastatic cancers pose a significant clinical problem worldwide and is among the main causes for cancer patient morbidity and mortality. Patients with advanced bone-metastatic diseases often present with either osteolytic or osteogenic bone diseases as their cancers progress. These bone pathologies are products of the cancer co-opting the local bone remodeling stroma to yield important growth nutrients and factors. Unfortunately, skeletal metastases remain incurable and are fatal. Identifying and understanding the causal multicellular and molecular interactions underlying skeletal malignancies can yield crucial ideas for targeting and inhibiting disease progression. …

Dcaf14 Promotes Stalled Fork Stability To Maintain Genome Integrity, Arik Townsend, Gabriella Lora, Justin Engel, Neysha Tirado-Class, Huzefa Dungrawala

Molecular Biosciences Faculty Publications

No abstract provided.

Tracking The Subcellular Localization Of Surface Proteins In Staphylococcus Aureus By Immunofluorescence Microscopy, Salvatore J. Scaffidi, Mac A. Shebes, Wenqi Yu

Molecular Biosciences Faculty Publications

Surface proteins of Staphylococcus aureus and other Gram-positive bacteria play essential roles in bacterial colonization and host-microbe interactions. Surface protein precursors containing a YSIRK/GXXS signal peptide are translocated across the septal membrane at mid-cell, anchored to the cell wall peptidoglycan at the cross-wall compartment, and presented on the new hemispheres of the daughter cells following cell division. After several generations of cell division, these surface proteins will eventually cover the entire cell surface. To understand how these proteins travel from the bacterial cytoplasm to the cell surface, we describe a series of immunofluorescence microscopy protocols designed to detect the stepwise …

Posttranslational Modification And Protein Disorder Regulate Protein-Protein Interactions And Dna Binding Specificity Of P53, Robin Levy

USF Tampa Graduate Theses and Dissertations

p53 is an intrinsically disordered transcription factor that suppresses tumor development by arresting the cell cycle and promoting DNA repair. p53 deletions or mutations can lead to cancer due to the inability of cells to respond to stress. The protein levels and post-translational modification state of p53 changes in response to cellular stress like DNA damage. Previous studies have shown that p53 can undergo coupled folding and binding with the E3 ubiquitin ligase, Mdm2, and the histone deacetylase, p300. In normal cells, p53 is kept at a low level by Mdm2, which marks it with ubiquitin, targeting p53 for proteasome …