Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 23 of 23

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Structural And Functional Characterization Of Hyper-Phosphorylated Grk5 Protein Expressed From E. Coli, Joseph M. Krampen, John Tesmer, Qiuyan Chen Aug 2018

Structural And Functional Characterization Of Hyper-Phosphorylated Grk5 Protein Expressed From E. Coli, Joseph M. Krampen, John Tesmer, Qiuyan Chen

The Summer Undergraduate Research Fellowship (SURF) Symposium

G protein-coupled receptor (GPCR) kinases (GRKs) are proteins in the cell responsible for regulating GPCRs located on the cell membrane. GRKs regulate active GPCRs by phosphorylating them at certain sites which causes them to stop normal signaling on the membrane. This ultimately affects how the cell responds to its environment. GRK5 is a kinase of particular interest due to its involvement in the pathology of diseases such as cardiac failure, cancers, and diabetes. Understanding the structure and function of GRK5 is essential for discovering ways to manipulate its behavior with these diseases, but not much is known about how GRK5 …


Tumor Formation In Response To Loss Of Chromatin Remodeler Chd5 In Zebrafish, Taylor R. Sabato, Erin L. Sorlien, Dr. Joseph P. Ogas Aug 2017

Tumor Formation In Response To Loss Of Chromatin Remodeler Chd5 In Zebrafish, Taylor R. Sabato, Erin L. Sorlien, Dr. Joseph P. Ogas

The Summer Undergraduate Research Fellowship (SURF) Symposium

Chromodomain helicase DNA binding protein 5 (CHD5) has been identified as a tumor suppressor in humans. Deletion or mutation of CHD5 has been observed in numerous cancers, including neuroblastoma and melanoma. We hypothesize that chd5 is also a tumor suppressor in zebrafish, a powerful model system to study tumorigenesis. Many genes involved in tumorigenesis are conserved in zebrafish, and they develop fully penetrant tumor phenotypes. We have created chd5 knock-out zebrafish using CRISPR/Cas9 and are monitoring them for tumor development. In addition to the chd5 knock-outs, we are undertaking a double-mutant approach by coupling loss …


Investigating The Effects Of Ph On Alphaviral E3-E2 Glycoprotein Association, Organization, And Cellular Tropism, Jason Michael Sequra Dec 2016

Investigating The Effects Of Ph On Alphaviral E3-E2 Glycoprotein Association, Organization, And Cellular Tropism, Jason Michael Sequra

Open Access Dissertations

In alphaviruses the role of E3 is required in protecting the fusion peptide region of E1 during intracellular transport. Throughout viral processing, the association of E2 and E3 is required for the successful trafficking and incorporation of E1 into the mature virion. This E3-E2 association has been observed to extend to mature virions in the solved structure for the envelope of Semliki Forest virus (SFV) and supported by the solved structure for the entire Venezuelan equine encephalitis virion (VEEV) with exclusive contacts being made between E3-E2. Immunization with monoclonal antibodies against VEEV E3 provided protection for mice challenged by lethal …


Nanobubbles Provide Theranostic Relief To Cancer Hypoxia, Christopher M. Long, Pushpak N. Bhandari, Joseph Irudayaraj Aug 2016

Nanobubbles Provide Theranostic Relief To Cancer Hypoxia, Christopher M. Long, Pushpak N. Bhandari, Joseph Irudayaraj

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hypoxia is a common motif among tumors, contributing to metastasis, angiogenesis, cellular epigenetic abnormality, and resistance to cancer therapy. Hypoxia also plays a pivotal role in oncological studies, where it can be used as a principal target for new anti-cancer therapeutic methods. Oxygen nanobubbles were designed in an effort to target the hypoxic tumor regions, thus interrupting the hypoxia-inducible factor-1α (HIF-1α) regulatory pathway and inhibiting tumor progression. At less than 100nm, oxygen nanobubbles act as a vehicle for site-specific oxygen delivery, while also serving as an ultrasound contrast agent for advanced imaging purposes. Through in vitro and in vivo studies, …


Intestinal Cytoplasmic Lipid Droplets, Associated Proteins, And The Regulation Of Dietary Fat Absorption, Theresa M. D'Aquila Aug 2016

Intestinal Cytoplasmic Lipid Droplets, Associated Proteins, And The Regulation Of Dietary Fat Absorption, Theresa M. D'Aquila

Open Access Dissertations

Dietary fat provides essential nutrients, contributes to energy balance, and regulates blood lipid concentrations. These functions are important to health, but can also become dysregulated and contribute to diseases such as obesity, diabetes, and cardiovascular disease. The small intestine absorbs dietary fat through an efficient multi step process of digestion, uptake, metabolism, and secretion or storage. When dietary fat is taken up by the absorptive cells of the small intestine, enterocytes, it can be secreted into circulation where it contributes to blood lipid levels or temporarily stored in cytoplasmic lipid droplets (CLDs). The objective of this dissertation is to investigate …


Axonal Transport And Life Cycle Of Mitochondria In Parkinson's Disease Model, Hyun Sung Apr 2016

Axonal Transport And Life Cycle Of Mitochondria In Parkinson's Disease Model, Hyun Sung

Open Access Dissertations

In neurons, normal distribution and selective removal of mitochondria are essential for preserving compartmentalized cellular function. Parkin, an E3 ubiquitin ligase associated with familial Parkinson’s disease, has been implicated in mitochondrial dynamics and removal. However, it is not clear how Parkin plays a role in mitochondrial turnover in vivo, and whether the mature neurons possess a compartmentalized Parkin-dependent mitochondrial life cycle. Using the live Drosophila nervous system, here, I investigate the involvement of Parkin in mitochondrial dynamics; organelle distribution, morphology and removal. Parkin deficient animals displayed less number of axonal mitochondria without disturbing organelle motility behaviors, morphology and metabolic state. …


Viewing The Extracellular Matrix: An Imaging Method For Tissue Engineering, Michael Drakopoulos, Sarah Calve Aug 2015

Viewing The Extracellular Matrix: An Imaging Method For Tissue Engineering, Michael Drakopoulos, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

The field of regenerative medicine seeks to create replacement tissues and organs, both to repair deficiencies in biological function and to treat structural damage caused by injury. Scaffoldings mimicking extracellular matrix (ECM), the structure to which cells attach to form tissues, have been developed from synthetic polymers and also been prepared by decellularizing adult tissue. However, the structure of ECM undergoes significant remodeling during natural tissue repair, suggesting that ECM-replacement constructs that mirror developing tissues may promote better regeneration than those modeled on adult tissues. This work investigated the effectiveness of a method of viewing the extracellular matrix of developing …


A Screen To Identify Saga-Activated Genes That Are Required For Proper Photoreceptor Axon Targeting In Drosophila Melanogaster, Kaelan J. Brennan, Vikki M. Weake, Jingqun Q. Ma Aug 2015

A Screen To Identify Saga-Activated Genes That Are Required For Proper Photoreceptor Axon Targeting In Drosophila Melanogaster, Kaelan J. Brennan, Vikki M. Weake, Jingqun Q. Ma

The Summer Undergraduate Research Fellowship (SURF) Symposium

The inherited human genetic disease spinocerebellar ataxia type 7 (SCA7) is characterized by progressive neurodegeneration and visual impairment that ultimately leads to blindness. SCA7 results from a mutation in the human ATXN7 gene that causes an expansion of polyglutamine tracts in this gene’s corresponding protein. Human ATXN7 protein serves as a component of the deubiquitylase (DUB) module of the large, multi-subunit complex Spt-Ada-Gcn acetyltransferase, or SAGA. SAGA is a transcriptional coactivator and histone modifier that functions to deubiquitylate histone H2B and allow for transcription of SAGA-mediated genes to occur. In Drosophila, mutations in SAGA DUB’s Nonstop and sgf11 components …


Elucidating The Role Of Hausp Ubiquitin Like Domains In The Catalytic Function Of Usp7, Anuj Patel, Nicole Davis, Andrew Mesecar Aug 2015

Elucidating The Role Of Hausp Ubiquitin Like Domains In The Catalytic Function Of Usp7, Anuj Patel, Nicole Davis, Andrew Mesecar

The Summer Undergraduate Research Fellowship (SURF) Symposium

Ubiquitin specific proteases (USPs) are a class of enzymes involved in myriad cellular processes. One USP of great interest due to its oncogenic properties is USP7. In normal conditions USP7 is closely regulated due to its responsibility for destabilizing the tumor suppressor, p53, through the deubiquitination of MDM2. In multiple myeloma cases, it appears the regulation of USP7 subsides, as it is largely overexpressed, leading to the inappropriate degradation of p53. Inhibition of USP7 could, therefore, prove a viable target for cancer therapy. A greater understanding of USP7’s function and structure can lead to more insight into how this enzyme …


A Model Of How Different Biology Experts Explain Molecular And Cellular Mechanisms, Caleb M. Trujillo, Trevor R. Anderson, Nancy J. Pelaez Jun 2015

A Model Of How Different Biology Experts Explain Molecular And Cellular Mechanisms, Caleb M. Trujillo, Trevor R. Anderson, Nancy J. Pelaez

PIBERG Publications

Constructing explanations is an essential skill for all science learners. The goal of this project was to model the key components of expert explanation of molecular and cellular mechanisms. As such, we asked: What is an appropriate model of the components of explanation used by biology experts to explain molecular and cellular mechanisms? Do explanations made by experts from different biology subdisciplines at a university support the validity of this model? Guided by the modeling framework of R. S. Justi and J. K. Gilbert, the validity of an initial model was tested by asking seven biologists to explain a molecular …


Analysis Of Chd Remodelers During Development: A Tale In Two Organisms, Brett Bishop Apr 2015

Analysis Of Chd Remodelers During Development: A Tale In Two Organisms, Brett Bishop

Open Access Dissertations

The correct development of different organisms requires the precise timing of genes important for development transitions. Organisms have recruited ATP-dependent chromatin remodelers to ensure the correct timing of gene expression during developmental transitions. Here I show how different CHD ATP-dependent chromatin remodelers regulate developmental transitions of different organisms. I show that PICKLE not only promotes H3K27me3 during development to repress developmental genes but also is targeted to these genes. The association of PICKLE to these genes suggests that both repression and H3K27me3 levels is a direct action of PICKLE on these loci. Using zebrafish as a model system, I show …


Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo Jan 2015

Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo

Open Access Dissertations

Biologists use mechanistic explanations to understand behaviors of the immense complexity of molecular and cellular systems. In undergraduate biology courses, students are expected to explain molecular and cellular mechanisms, but teaching this skill presents many challenges due to the highly abstract, intangible nature of the cellular world, the influence of everyday language, and the tendency of students to overestimate how much they can explain. Therefore, across three studies this dissertation addresses these obstacles to teach undergraduate biology students to explain molecular and cellular mechanisms. ^ The first step was to model how biology experts explain molecular and cellular mechanisms, and …


Associated Behavioral, Genetic, And Gene Expression Variation With Alternative Life History Tactics In Salmonid Fishes, Ashley Chin-Baarstad Oct 2014

Associated Behavioral, Genetic, And Gene Expression Variation With Alternative Life History Tactics In Salmonid Fishes, Ashley Chin-Baarstad

Open Access Dissertations

Individual differences in behavior can have potential fitness consequences and often reflect underlying genetic variation. My research focuses on three objectives related to individual level variation: 1) evaluating the innate behavioral variation within and between individuals, families, and progeny of different life-history types across time; 2) testing for differences in gene expression within the brain associated with this behavioral variation; and 3) using genetic polymorphisms to test for associations with ecotype, as well as population structure, in polymorphic populations. First, we evaluated the variation in a suite of ecologically relevant behaviors across time in juvenile progeny produced from crosses within …


Intranuclear Strain Measured By Iterative Warping In Cells Under Mechanical And Osmotic Stress, Jonathan T Henderson Oct 2014

Intranuclear Strain Measured By Iterative Warping In Cells Under Mechanical And Osmotic Stress, Jonathan T Henderson

Open Access Dissertations

The nucleus is a membrane bound organelle and regulation center for gene expression in the cell. Mechanical forces transfer to the nucleus directly and indirectly through specific cellular cytoskeletal structures and pathways. There is increasing evidence that the transferred forces to the nucleus orchestrate gene expression activity. Methods to characterize nuclear mechanics typically study isolated cells or cells embedded in 3D gel matrices. Often report only aspect ratio and volume changes, measures that oversimplify the inherent complexity of internal strain patterns. This presents technical challenges to simultaneously observe small scale nuclear mechanics and gene expression levels inside the nuclei of …


Electrophoresis Staining: A New Method Of Whole Mount Staining, Mitchell G. Ayers, Sarah Calve, Zhiyu Li Aug 2014

Electrophoresis Staining: A New Method Of Whole Mount Staining, Mitchell G. Ayers, Sarah Calve, Zhiyu Li

The Summer Undergraduate Research Fellowship (SURF) Symposium

Advances in tissue clearing techniques have allowed almost a ten-fold increase in the viewing depth of confocal microscopy. This allows for intact cellular structures to be rendered in 3D. However, viewing tissues to this depth is often limited to endogenous fluorescence as passive diffusion of antibodies via whole mount staining can take weeks. Our lab is developing a new method involving electrophoresis as a driving force that will promote active antibody binding deep into tissue, reducing the amount of time needed to stain for cellular structures. Due to the inherent charge within antibodies, they are able to be directionally forced …


Key Residues Of Human Cytoplasmic Protein Tyrosine Phosphatase-A And -B For Substrate Binding And Specificity, Byunghyun Park Jul 2014

Key Residues Of Human Cytoplasmic Protein Tyrosine Phosphatase-A And -B For Substrate Binding And Specificity, Byunghyun Park

Open Access Theses

Reversible tyrosine phosphorylation plays an important role in signaling pathways that are essential for regulating cellular growth, differentiation and metabolism. Moreover, several human diseases such as diabetes, obesity and cancers are associated with the deregulation of protein tyrosine phosphatases (PTPs). Several studies provide evidence that PTPs not only contribute to cellular differentiation, but over-expression of these molecules also leads to transformation of non-transfomed cells as well. Based on these results, designing specific PTP inhibitors may ultimately function as potential therapeutic agents to treat various diseases including cancer, diabetes, and autoimmune diseases. EphA2 is a receptor tyrosine kinase which is hypo-phosphorylated …


Neurotrophins And Their Effects On Breast Cancer Cell Proliferation And Migration, Kayla Elise Minser Apr 2014

Neurotrophins And Their Effects On Breast Cancer Cell Proliferation And Migration, Kayla Elise Minser

Open Access Theses

Cancer is a large health issue in all parts of the world. In the United States alone, approximately 1 in 4 deaths are cancer related. Breast cancer is a particularly prevalent form, accounting for a little over 14 percent of all cancer incidence. The largest obstacle to overcome for breast cancer morbidity is metastasis. Over 90 percent of all breast cancer related deaths are due to metastasis. Because metastasis is a complex, multi-step process, it is difficult to treat. A recent observation in the Kirshner lab has revealed a type of phenotypic plasticity, where migratory cancer cells have a neuronal-like …


Study Of Coronavirus Protease Using Cfp-Yfp Fluorescent Assay, Caitlin E. Specht, Andrew Mesecar Ph.D., Katrina Molland Ph.D. Oct 2013

Study Of Coronavirus Protease Using Cfp-Yfp Fluorescent Assay, Caitlin E. Specht, Andrew Mesecar Ph.D., Katrina Molland Ph.D.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Middle Eastern Respiratory Syndrome (MERS) is an emerging viral disease originating in the Arabian Peninsula with a current mortality rate of nearly fifty percent throughout Europe and Asia according to the World Health Organization. Characterization of this disease is being done to understand the basis of viral replication. One target for viral inhibition are replication proteases. Replication proteases are enzymes that cleave proteins specific to cell growth and reproduction that form the viral replicase complex making them an ideal target for viral replication inhibition. First, replication proteases were characterized using a fluorescence resonance energy transfer (FRET) construct by measuring the …


Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs Oct 2013

Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Set1 complex, a histone methyltransferase complex found in S. cerevisiae (budding yeast), is the only histone methyltransferase responsible for catalyzing methylation of histone H3 at Lysine 4. It possesses homologues in other species, humans included. While yeast only have the Set1 complex, the human homologues of the yeast Set1 complex include mixed-lineage leukemia family (MLL1-4), Set1 A, Set1 B, among others. MLL1-4 has been shown to play a role in transcription, cell type specification, and the development of leukemia. One application of characterizing the role of a protein is that the information gained can provide insight into the function …


The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve Oct 2013

The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

To improve the treatment of musculoskeletal injuries, a better understanding of the transitional environment in which progenitor cells form mature musculoskeletal constructs is necessary. This need arises because injury repair requires restructuring of tissue, similar to the initial tissue construction that occurs during embryonic development by progenitor cells. Differences in both the biochemical and mechanical environments between a transitional and a differentiated state are known to take place, but how these differences affect cell behavior had not yet been characterized in mammalian tendon cells. In order to investigate this, we have determined the effects of exogenous extracellular matrix and the …


Measuring And Modeling The Response Characteristics Of The Environmental Phosphate Transducer In Escherichia Coli, Chetan Sood Oct 2013

Measuring And Modeling The Response Characteristics Of The Environmental Phosphate Transducer In Escherichia Coli, Chetan Sood

Open Access Dissertations

The PhoR/PhoB two-component system in Escherichia coli is a biological transducer that senses the limitation of environmental inorganic orthophosphate, the bacteria's preferred source of the essential nutrient phosphate, and transmits that information to the interior of the cell initiating a response that mitigates phosphate starvation. In the first part of this study, we present and apply a fluorescence microscopy technique to measure, in vivo, the dynamic response characteristics of the transducer with single-cell resolution. We report that the transience in the PhoR/PhoB TCS response is consistent with the transducer having a threshold sensitivity to the concentration of environmental phosphate, …


Interaction Between Centromeric Histone H3 Variant And Shugoshin, Visarut Buranasudja Jan 2013

Interaction Between Centromeric Histone H3 Variant And Shugoshin, Visarut Buranasudja

Open Access Theses

Precise and faithful segregation of chromosome segregation during mitosis depends on the ability of the cell to regulate chromosome bi-orientation on the mitotic spindle. Shugoshin (Sgo1), the protector of meiotic centromeric cohesin, is required for proper establishment of chromosome bi-orientation. Sgo1 plays a crucial role as part of a mitotic tension sensor between sister chromatids. Recently, Sgo1 has been reported to interact with histone H3 at the pericentromere region, as an important factor for tension sensing and chromosome segregation. However, the role of Sgo1 in tension sensing at centromere is still elusive. The centromere is the region of attachment of …


Combating Bioterrorism: Purification And Structural Analysis Of The E3 Proteins Of The Venezuelan Equine Encephalitis Virus And The Chikungunya Virus, Tyshia Gwin Jul 2011

Combating Bioterrorism: Purification And Structural Analysis Of The E3 Proteins Of The Venezuelan Equine Encephalitis Virus And The Chikungunya Virus, Tyshia Gwin

The Journal of Purdue Undergraduate Research

Outbreaks of the Venezuelan Equine Encephalitis Virus (VEEV) and the Chikungunya Virus (CHIKV) continue to emerge in Central and South America, Africa, and Asia, but there are currently no vaccines or anti-virals for these viruses. Given their ease of transmission, debilitating symptoms, and genetic alterability, VEEV and CHIKV have great potential for development into biological weapons. Therefore, there is an urgent need to determine possible methods of treatment or prevention. One possibility of prevention lies in determining the structure and biological function of the E3 protein that plays a key role in the infectivity of the viruses. In this research, …