Molecular Biology Commons^™

Regulation Of P53 By Trpm6 And Trpm7, Thomas Whitbread

Theses and Dissertations

TRPM6 and TRPM7 are two divalent metal cation channels that also possess a serine/threonine kinase domain. They both play critical roles in cellular and organismal metal homeostasis, and are necessary for proper embryonic development and human health. They may function independently in homomeric units, or act together as heterotetramers that display unique characteristics compared to the homomeric channels. These channel-kinases have increasingly been linked to cancer, displaying altered expression levels in a variety of human cancers and contributing to disease progression. Prior work has shown that TRPM6 and TRPM7 can participate in cancer-related signaling pathways. Here, the potential for TRPM6 …

Comparing The Performance Of A Targeted Pull-Down Assay To Shotgun Sequencing For Improving Respiratory Infectious Disease Surveillance, Monica R. Christian

Browse all Theses and Dissertations

Current surveillance focuses on well characterized pathogens such as influenza. Since 2000, there have been multiple outbreaks of respiratory disease. These outbreaks have demonstrated the need for robust and collaborative global efforts to identify, monitor, and contain novel respiratory viruses. This study aims to improve the ability of public health agencies to monitor and respond to respiratory disease outbreaks. Using five respiratory pathogens, this study compares a molecular capture technology from Twist Biosciences to the shotgun sequencing approach of whole transcriptome amplification (WTA, Qiagen) with the goal of determining which method is most effective using cost, usability, and sequencing quality …

Trichloroethylene (Tce) And Metabolite S-(1,2-Dichlorovinyl)-L-Cysteine (Dcvc) Alters Pregnancy Mediators In Rat Amniotic Fluid And Thp-1 Cells, Audrey Luce, Lyric Johnson, Karena Moleakunnel, Eleanor Scheeres, Emily Schellenboom, Sean Harris, Erica Boldenow

Summer Research

• Proinflammatory cytokines, such as TNF-α recruit immune cells to help fight infection and aid in cervical ripening (i.e. dilation).

• Matrix metalloproteinases (MMPs) such as MMP-9 help with rupture of the gestational membranes (i.e. breaking of the water).

• Prostaglandins, such as PGE2 contribute to myometrial contractions and labor induction.

• Working pregnant women are exposed to both toxicants and pathogens which can contribute to adverse birth outcomes such as preterm birth.

Molecular And Systemic Epigenetic Inheritance: Integrating Development, Genetics, And Evolution, Robert Lickliter, David S. Moore

Pitzer Faculty Publications and Research

Currently, a central problem for theoretical biology is the integration of development with genetics and evolutionary theory. Through the late 20^th century, biologists held that animals resemble their ancestors strictly because of the transgenerational transmission of DNA. This view effectively wrote development out of evolutionary biology. However, many molecular and developmental biologists now understand that phenotypes—anatomical, physiological, and behavioral traits—are not determined by genes (i.e., DNA segments) alone; instead, they emerge epigenetically from developmental processes involving co-acting genetic factors, environmental factors, molecular epigenetic factors, and other non-genetic factors within organisms’ bodies. This insight forces a rethinking of biological inheritance. …

Effect Of Molecular Crowders On The Activation Of Cholera Toxin By Protein Disulfide Isomerase, Niral Shah

Honors Undergraduate Theses

Cholera toxin (CT) is a classic A-B type protein toxin that has an A subunit (A1 + A2) and a pentameric B subunit. The catalytic A1 domain is linked to the A2 domain via a disulfide linkage. CTA1 must be dissociated from the rest of the toxin to cause a cytopathic effect. Protein disulfide isomerase (PDI) can reduce the CTA1/CTA2 disulfide bond, but disassembly of the reduced toxin requires the partial unfolding of PDI that occurs when it binds to CTA1. This unfolding event allows PDI to push CTA1 away from the rest of the toxin.

My research question is …

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 …

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 …

Establishing A Biochemical System For The Purification And Atpase Activity Of Gst-Dbp5, Sarah Utley, Rachel E. Rigsby Phd, Rebecca L. Adams Phd

Science University Research Symposium (SURS)

The export of mRNA out of the nucleus is a crucial step for eukaryotic gene expression. The export of mRNA transcripts is aided by Mex67, which allows export through the nuclear pore complex doorways in the nuclear envelope. Once out of the nucleus, a protein known as Dbp5, bound to ATP, Gle1, and Nup42 aids in the directionality of mRNA export by helping remove Mex67 from the mRNA strand. Following interaction with RNA, Dbp5 then hydrolyzes ATP so that it unbinds the mRNA, allowing for enzyme recycling. The goal of this study is to explore the ATPase activity of Saccharomyces …

Detecting Linc Complex Mps3 And Nuclear Pore Complex Ndj1 Protein Interactions On Yeast Nuclear Membrane S Through Fluorescence Microscopy, Dean Boecher, Rebecca Adams

Science University Research Symposium (SURS)

Though cancer cells have been shown to have abnormal nuclear morphologies and responses to mechanical forces, the mechanisms of how mechanical stress is translated into cellular action and structural reorganization within the nuclear envelope are largely unexplored. The Linker of Nucleoskeleton and Cytoskeleton (LINC) complex is a transmembrane protein complex that connects the actin cytoskeleton to the lamin nucleoskeleton, enabling mechanical forces to be translated between the cytoplasm and the nucleus. In cells exposed to physical stress, nuclear pore complexes (NPCs) –which control the exchange of biochemical signals and macromolecules in and out of the nucleus through mRNA export –have …

Analyzing Mex67 Interaction With The Ssa4 Transcript For Selective Export, Gretchen E. Stalnaker, Rebecca Adams

Science University Research Symposium (SURS)

In eukaryotic cells, such as the budding yeast Saccharomyces cerevisiae, mRNA export is the essential process in which mature mRNA is transported from its site of production, the nucleus, through the nuclear pore complex (NPC) to the cytoplasm, where it can then be translated into protein. This is accomplished when a transcript interacts with the mRNA export protein Mex67, which shuttles the message across the NPC. When the cell is under conditions of stress, such as heat shock, most mRNA export is prohibited, allowing for selective gene expression that prioritizes cell recovery. Specifically, SSA4, which encodes a protein that …

Testing Ssa4:Ade3 Reporters For Mcs Screening, Karah Edmonds, Rebecca Adams

Science University Research Symposium (SURS)

In eukaryotic cells, after transcription, mRNA is escorted from the nucleus to the cytoplasm to be translated. This process, called mRNA export, is essential for gene expression. However, when the cell exists in stressful conditions, mRNA export becomes regulated, and only select transcripts, including the stress-responsive SSA4 mRNA, can be exported. This project aims to uncover the mechanism of selective SSA4 mRNA export by generating a reporter that enables phenotypically visible expression under stressful conditions. Specifically, the ADE3 ORF was placed under the regulatory sequence of SSA4, which was anticipated to induce a red color for colonies only following stress. …

Rnai-Mediated Gene Silencing In The Exotic Redbay Ambrosia Beetle, Xyleborus Glabratus, And Insect-Fungal Interactions Within The Laurel Wilt Complex, Morgan Christine Knutsen

Theses and Dissertations--Entomology

Laurel wilt disease (LWD) is a lethal vascular disease impacting lauraceous hosts caused by Harringtonia lauricola, the fungal symbiont of the redbay ambrosia beetle (Xyleborus glabratus Eichoff) (RAB) (Coleoptera: Curculionidae). LWD has caused tree mortality throughout the southeastern United States and is continuing to spread into new regions. Current management methods have not been successful in preventing spread, warranting investigation into innovative techniques including RNA interference (RNAi).

Elongation factor-1 alpha (ef1a) and actin (act) were established as stably expressed reference genes after exposing beetles to different photoperiod, temperature, and dsRNA exposure. After RAB oral …

Regulation Of Erk3 By Kras Signalling And Its Role In The Growth Of Lung Adenocarcinoma (Luad) Cells, Shreya Akunapuram

Browse all Theses and Dissertations

Extracellular signal related kinase 3 (ERK3) is one of the atypical mitogen activated protein kinases (MAPK). It is expressed ubiquitously and plays a role in a variety of cellular processes, including cell growth and differentiation. ERK3’s role in promoting migration and invasion in various cancers has been well established. ERK3 is upregulated in non-small cell lung cancers (NSCLCs) and has been shown to promote NSCLC tumor growth and progression. However, the regulation of ERK3 in lung cancers remains largely unclear. A recent study indicates that ERK3 phosphorylation at S189, an indicator of ERK3 activity, is upregulated by KRAS in NSCLCs. …

Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson

College of Graduate Studies: Theses & Dissertations

Epigenetics is the study of molecular modification of a genome without changing its base pairs. The most studied type of epigenetic mechanism is DNA methylation, which is capable of turning a gene “on” or “off.” Epigenetic potential is the capacity to which an individual can have methylation on its genome. The more CpGs available, the greater the epigenetic potential. In invasive species, genetic variation has been observed to be paradoxical: not much of it exists on a genomic level, but epigenetically, phenotypic variation can occur. The focus on shift in gene expression in this study is on Toll-Like Receptor 4 …

Effects Of Depth, Distance To Shore, And Water Velocity On Organismal And Extra-Organismal Environmental Dna Concentrations In A Large River, Dylan Keel

Cal Poly Humboldt theses and projects

Environmental DNA (eDNA) is a sensitive tool for detection of aquatic species and concentrations of eDNA in water samples have been useful for estimating abundance. This study evaluated the effects of depth, distance to shore, and water velocity on the concentration of organismal and extra-organismal eDNA concentrations in the Klamath River, California (basin area ≅ 40,000 km²). At each of six river cross sections 32 water samples were collected, including surface samples and depth samples evenly distributed across the cross section, and eDNA concentrations were determined for the parasite Ceratonova shasta and Chinook salmon, Oncorhynchus tshawytscha, using …

The Role Of Myocardin In The Progression Of Non-Small Cell Lung Cancer, Soromidayo Akinsiku

Biotechnology Theses

Lung cancer is the leading cause of cancer-related mortality in the world and NSCLC accounts for 85% of all lung cancer cases. The mainstay of treatment for patients with stage I, II and IIIA NSCLC is surgery, followed by post-operative cisplatin-based chemotherapy. Additional adjuvant therapy involving targeted tyrosine kinase inhibitors has been in use, however even for the targeted therapy, resistance eventually develops. Therefore, there is a need for identifying novel targets for this life-threatening disease. Given that preliminary studies in Ikebe lab revealed that myocardin knockdown significantly promoted caspase-3 degradation, in this study, using myocardin siRNA, we investigated the …

Development And Biological Evaluation Of Selective Small-Molecule Inhibitors Of The Human Cytochrome P450 1b1, Austin Hachey

Theses and Dissertations--Chemistry

The human cytochrome P450 1B1 (CYP1B1) is an emerging target for small- molecule therapeutics. Several solid tumors overexpress CYP1B1 to the degree that it has been referred to as a universal tumor antigen. Conversely, its expression is low in healthy tissues. CYP1B1 may drive tumorigenesis through promoting the formation of reactive toxins from environmental pollutants or from endogenous hormone substrates. Additionally, the expression of CYP1B1 in tumors is associated with resistance to several common chemotherapies and with poor prognoses in cancer patients. However, inhibiting CYP1B1 with small molecules has been demonstrated in cellular and murine model systems to reverse this …

Characterization Of Parp1-Dependent Poly-Adp-Ribosylation Of Sprtn, Quincee Simonson

Electronic Theses and Dissertations

DNA-protein crosslinks (DPCs) are a type of DNA lesion that form when proteins become covalently linked to DNA. It is estimated that replicating cells experience approximately 6,000 DPCs per day per genome during exponential growth (Ruggiano & Ramadan, 2021). If left unrepaired, DPCs can be lethal to cells. For this reason, cells have evolved multiple pathways to repair or bypass DPCs to survive. One such pathway involves SPRTN, a nuclear metalloprotease that plays a key role in the repair of DPCs through direct proteolysis (Lopez-Mosqueda et al., 2016; Vaz et al., 2016). Once SPRTN degrades the bulky protein component of …

Approaches To Avoid Proteolysis During Protein Expression And Purification, Gary T. Henehan, Barry J. Ryan, Gemma K. Kinsella

Books/Book Chapters/ Proceedings

All cells contain proteases, which hydrolyze the peptide bonds between amino acids of a protein backbone. Typically, proteases are prevented from nonspecific proteolysis by regulation and by their physical separation into different subcellular compartments; however, this segregation is not retained during cell lysis, which is the initial step in any protein isolation procedure. Prevention of proteolysis during protein purification often takes the form of a two-pronged approach: first, inhibition of proteolysis in situ, followed by the early separation of the protease from the protein of interest via chromatographic purification. Protease inhibitors are routinely used to limit the effect of the …