Medical Biochemistry Commons^™

Understanding Blue Light Retinal Damages And The Methods Of Prevention, Amelia Lee

Senior Honors Theses

Light emitting diode (LED) lights that comprise television screens, phone displays, laptops, and tablets have been studied by scientists in order to understand the implications of blue light radiation and the effects that it has on the human body—especially the retina of the eye. The retina is comprised of highly metabolic cells, and when those cells are placed under oxidative stress, death occurs causing ocular disease. Additionally, excess blue light exposure causes shifts in biological rhythms that govern patterns of alertness and sleep. Recently scientists began studying the methods of blue light prevention. Some studies show that blue light radiation …

A Characterization Of Rgnef Biophysical Properties And Interactome, Brooke E. Wile

Electronic Thesis and Dissertation Repository

ALS is a progressive and fatal neurodegenerative disorder whose pathologic hallmark is the presence of neuronal cytoplasmic inclusions (NCIs). In approximately 97% of ALS cases, NCIs are found to be TDP-43+. Rho-guanine nucleotide exchange factor (RGNEF) has recently been implicated in ALS pathophysiology through its co-localization and coimmunoprecipitation with TDP-43+. RGNEF has also been shown to harbour cytoprotective effects in the N-terminal region and is responsible for the regulation of low molecular weight-neurofilament (NFL), intimately involved neural structure, through its predicted RNA-binding domain (RBD). This study looked to purify constructs of RGNEF through nickel immobilized metal affinity chromatography (Ni-IMAC) and …

Tera-Seq: True End-To-End Sequencing Of Native Rna Molecules For Transcriptome Characterization, Fadia Ibrahim, Jan Oppelt, Manolis Maragkakis, Zissimos Mourelatos

Department of Biochemistry and Molecular Biology Faculty Papers

Direct sequencing of single, native RNA molecules through nanopores has a strong potential to transform research in all aspects of RNA biology and clinical diagnostics. The existing platform from Oxford Nanopore Technologies is unable to sequence the very 5′ ends of RNAs and is limited to polyadenylated molecules. Here, we develop True End-to-end RNA Sequencing (TERA-Seq), a platform that addresses these limitations, permitting more thorough transcriptome characterization. TERA-Seq describes both poly-and non-polyadenylated RNA molecules and accurately identifies their native 5′ and 3′ ends by ligating uniquely designed adapters that are sequenced along with the transcript. We find that capped, full-length …

Expression And Purification Of Phage T7 Ejection Proteins For Cryo-Em Analysis, Nicholas A. Swanson, Ravi K Lokareddy, Fenglin Li, Chun-Feng Hou, Mikhail Pavlenok, Michael Niederweis, Gino Cingolani

Department of Biochemistry and Molecular Biology Faculty Papers

Bacteriophages of the Podoviridae family densely package their genomes into precursor capsids alongside internal virion proteins called ejection proteins. In phage T7 these proteins (gp14, gp15, and gp16) are ejected into the host envelope forming a DNA-ejectosome for genome delivery. Here, we describe the purification and characterization of recombinant gp14, gp15, and gp16. This protocol was used for high-resolution cryo-EM structure analysis of the T7 periplasmic tunnel and can be adapted to study ejection proteins from other phages. For complete details on the use and execution of this protocol, please refer to Swanson et al.

Inability To Switch From Arid1a-Baf To Arid1b-Baf Impairs Exit From Pluripotency And Commitment Towards Neural Crest Formation In Arid1b-Related Neurodevelopmental Disorders, Luca Pagliaroli, Patrizia Porazzi, Alyxandra T Curtis, Chiara Scopa, Harald M M Mikkers, Christian Freund, Lucia Daxinger, Sandra Deliard, Sarah A Welsh, Sarah Offley, Connor A Ott, Bruno Calabretta, Samantha A Brugmann, Gijs W E Santen, Marco Trizzino

Department of Biochemistry and Molecular Biology Faculty Papers

Subunit switches in the BAF chromatin remodeler are essential during development. ARID1B and its paralog ARID1A encode for mutually exclusive BAF subunits. De novo ARID1B haploinsufficient mutations cause neurodevelopmental disorders, including Coffin-Siris syndrome, which is characterized by neurological and craniofacial features. Here, we leveraged ARID1B+/- Coffin-Siris patient-derived iPSCs and modeled cranial neural crest cell (CNCC) formation. We discovered that ARID1B is active only during the first stage of this process, coinciding with neuroectoderm specification, where it is part of a lineage-specific BAF configuration (ARID1B-BAF). ARID1B-BAF regulates exit from pluripotency and lineage commitment by attenuating thousands of enhancers and genes of …

Creating Tools To Study The Signaling And Function Of The Adhesion Family Of Gpcrs, Victor M. Mirka

Electronic Thesis and Dissertation Repository

Adhesion GPCRs (aGPCRs) are difficult to study because they are activated by mechanical force. aGPCRs are autoproteolytically cleaved into N-terminal and C-terminal fragments. Mechanical force removes the N-terminal fragment revealing a tethered ligand activating the receptor. Proteinase Activated Receptors (PARs) are N-terminally cleaved by proteinases revealing a tethered ligand activating the receptor. We hypothesized the tethered ligand of aGPCRs could be revealed by replacing the N-terminal fragment with a PAR N-terminus. We fused the PAR2 N-terminus to the C-terminal fragments of four aGPCRs: CD97, EMR2, GPR56, and BAI1. PAR2-aGPCR chimeric receptors dose dependently recruited G-proteins and β-arrestins, supporting our hypothesis. …

Multifunctionality Of Prostatic Acid Phosphatase In Prostate Cancer Pathogenesis, Evgenia Alpert, Armin Akhavan, Arie Gruzman, William J. Hansen, Joshua Lehrer-Graiwer, Steven C. Hall, Eric Johansen, Sean Mcallister, Mittul Gulati, Ming-Fong Lin, Vishwanath R Lingappa

Journal Articles: Biochemistry & Molecular Biology

The role of human prostatic acid phosphatase (PAcP, P15309|PPAP_HUMAN) in prostate cancer was investigated using a new proteomics tool termed signal sequence swapping (replacement of domains from the native cleaved amino terminal signal sequence of secretory/membrane proteins with corresponding regions of functionally distinct signal sequence subtypes). This manipulation preferentially redirects proteins to different pathways of biogenesis at the endoplasmic reticulum (ER), magnifying normally difficult to detect subsets of the protein of interest. For PAcP, this technique reveals three forms identical in amino acid sequence but profoundly different in physiological functions, subcellular location, and biochemical properties. These three forms of PAcP …

Physiological Roles Of Mammalian Transmembrane Adenylyl Cyclase Isoforms, Katrina F. Ostrom, Justin E. Lavigne, Tarsis F. Brust, Roland Seifert, Carmen Dessauer, Val J. Watts, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors. The transmembrane ACs display varying expression patterns across tissues, giving potential for them having a wide array of physiologic roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gα_s so it was long assumed that all ACs are activated by Gα_s-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form …

Regulatory Function Of The Anticoagulant Protein S In Patients With Chuvashpolycythemia, Devin M. Melancon, Verima Pereira, Rinku Majumder

Medical Student Research Poster Symposium

Background: Chuvash polycythemia is a hematological disorder that is present worldwide but endemic to the Chuvash population, a Turkish ethnic group, in Russia. The disorder is caused by a homozygous germline mutation (R200W) in the von Hippel Lindau gene. This mutation impairs binding of pVHL to hypoxia-inducible factor 1-alpha (HIF-1α); lack of this interaction prevents degradation of HIF-1α. The resultant upregulation of HIF-1α, even in a normal oxygen state, increases the activity of erythropoietin, thereby causing polycythemia. Affected individuals experience increased rates of arterial and venous thrombosis unrelated to the increased concentration of hemoglobin. Aims: To determine whether upregulation of …

Novel Biomarkers For Early And Accurate Detection Of A Fatal Gut Inflammatory Diseasein Preemie Babies, Lana Thaljeh, Rebecca Buckley, Anne Tufton, Maya Heath, Brian Barkemeyer, Zhide Fang, Lee Mcdaniel, Andrew Chapple, Kelly Laborde, Beverly Ogden, Misty Good, Duna Penn, Steven Spedale, Sunyoung Kim

Medical Student Research Poster Symposium

Necrotizing enterocolitis (NEC) is an inflammatory disease that primarily affects the intestinal tract of premature and low birthweight infants. It is one of the most common complications that occur with prematurity, which also results in high morbidity and mortality due to unchecked pathogenic bacterial growth. The median time between death and x-ray diagnosis is 1 day and, currently, there are no reliable molecular methods to predict the onset of NEC in infants. Association of intestinal alkaline phosphatase (iAP) with moderate and severe forms of the disease suggested that iAP can be a diagnostic tool that is accurate and specific for …

Cellular Origins Of Egfr-Driven Lung Cancer Cells Determine Sensitivity To Therapy, Fan Chen, Jinpeng Liu, Robert M. Flight, Kassandra J. Naughton, Alexsandr Lukyanchuk, Abigail R Edgin, Xiulong Song, Haikuo Zhang, Kwok-Kin Wong, Hunter N. B. Moseley, Chi Wang, Christine F. Brainson

Toxicology and Cancer Biology Faculty Publications

Targeting the epidermal growth factor receptor (EGFR) with tyrosine kinase inhibitors (TKIs) is one of the major precision medicine treatment options for lung adenocarcinoma. Due to common development of drug resistance to first- and second-generation TKIs, third-generation inhibitors, including osimertinib and rociletinib, have been developed. A model of EGFR-driven lung cancer and a method to develop tumors of distinct epigenetic states through 3D organotypic cultures are described here. It is discovered that activation of the EGFR T790M/L858R mutation in lung epithelial cells can drive lung cancers with alveolar or bronchiolar features, which can originate from alveolar type 2 (AT2) cells …

Atomistic Simulations And In Silico Mutational Profiling Of Protein Stability And Binding In The Sars-Cov-2 Spike Protein Complexes With Nanobodies: Molecular Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Deniz Yasar Oztas, Grace Gupta

Mathematics, Physics, and Computer Science Faculty Articles and Research

Structure-functional studies have recently revealed a spectrum of diverse high-affinity nanobodies with efficient neutralizing capacity against SARS-CoV-2 virus and resilience against mutational escape. In this study, we combine atomistic simulations with the ensemble-based mutational profiling of binding for the SARS-CoV-2 S-RBD complexes with a wide range of nanobodies to identify dynamic and binding affinity fingerprints and characterize the energetic determinants of nanobody-escaping mutations. Using an in silico mutational profiling approach for probing the protein stability and binding, we examine dynamics and energetics of the SARS-CoV-2 complexes with single nanobodies Nb6 and Nb20, VHH E, a pair combination VHH E + …

Targeting The Cdk6 Dependence Of Ph+ Acute Lymphoblastic Leukemia, Patrizia Porazzi, Marco De Dominici, Joseph Salvino, Bruno Calabretta

Department of Cancer Biology Faculty Papers

Ph+ ALL is a poor-prognosis leukemia subtype driven by the BCR-ABL1 oncogene, either the p190-or the p210-BCR/ABL isoform in a 70:30 ratio. Tyrosine Kinase inhibitors (TKIs) are the drugs of choice in the therapy of Ph+ ALL. In combination with standard chemotherapy, TKIs have markedly improved the outcome of Ph+ ALL, in particular if this treatment is followed by bone marrow transplantation. However, resistance to TKIs develops with high frequency, causing leukemia relapse that results in

Subtype-Selective Positive Modulation Of KCa 2 Channels Depends On The Ha/Hb Helices, Young-Woo Nam, Meng Cui, Naglaa Salem, Razan Orfali, Misa Nguyen, Grace Yang, Mohammad Asikur Rahman, Judy Lee, Miao Zhang

Pharmacy Faculty Articles and Research

Background and Purpose

In the activated state of small-conductance Ca2+-activated potassium (KCa 2) channels, calmodulin interacts with the HA/HB helices and the S4-S5 linker. CyPPA potentiates KCa 2.2a and KCa 2.3 channel activity but not the KCa 2.1 and KCa 3.1 subtypes.

Experimental Approach

Site-directed mutagenesis, patch-clamp recordings and in silico modeling were utilized to explore the structural determinants for the subtype-selective modulation of KCa 2 channels by CyPPA.

Key Results

Mutating residues in the HA (V420) and HB (K467) helices of KCa 2.2a channels to their equivalent residues in KCa 3.1 channels diminished the potency of CyPPA. CyPPA elicited …

The Effects Of Estrogen In The Glucoregulatory Response To Exercise In Type 1 Diabetes, Mitchell James Sammut

Undergraduate Student Research Internships Conference

Regular exercise has shown to benefit the health of individuals with type 1 diabetes mellitus (T1DM). However, a barrier to regular exercise for this population is the fear of low blood glucose (BG) levels, also known as hypoglycemia. Hypoglycemia can result in short and long-term side-effects, such as recurring loss of consciousness or in severe cases death.

In non-diabetics, sex-related differences in fuel selection during exercise are well established. Women shift towards using fats as fuel whereas men rely mostly on sugars (i.e., carbohydrates) for energy production. Exercise during the luteal phase of the female menstrual cycle, where estrogen levels …

The Penn State Protein Ladder System For Inexpensive Protein Molecular Weight Markers, Ryan T Santilli, John E Williamson, Yoshitaka Shibata, Rosalie P Sowers, Andrew N. Fleischman, Song Tan

Department of Anesthesiology Faculty Papers

We have created the Penn State Protein Ladder system to produce protein molecular weight markers easily and inexpensively (less than a penny a lane). The system includes plasmids which express 10, 15, 20, 30, 40, 50, 60, 80 and 100 kD proteins in E. coli. Each protein migrates appropriately on SDS-PAGE gels, is expressed at very high levels (10–50 mg per liter of culture), is easy to purify via histidine tags and can be detected directly on Western blots via engineered immunoglobulin binding domains. We have also constructed plasmids to express 150 and 250 kD proteins. For more efficient production, …

Thermal Properties Of 18f-Fdg Uptake And Imaging In Positron Emission Tomography Scans Of Cancerous Cells, Carleigh R. Eagle

PANDION: The Osprey Journal of Research and Ideas

Positron Emission Tomography (PET) scans can utilize a radioactive tracer, in this case 2-deoxy2-[fluorine-18] fluoro-D-glucose (¹⁸F-FDG), to visualize malignant tumors in cancer patients. The uptake was compared to glucose to understand the difference in thermal properties, which contribute to the ability to image the cancerous cells. The uptake of ¹⁸F-FDG by cancer cells and the imaging process of positron emission tomography were reviewed from a thermodynamic perspective. Gastrointestinal and neurological imaging techniques were reviewed to understand the role of PET imaging in different areas of the human body.

Nucleotide P2y₂ Receptor-Dependent Leukocyte-Endothelial Interaction, Spencer E. Thomas

MSU Graduate Theses

Extracellular nucleotides (ATP, UTP) released from cells act on nucleotide receptors to promote vascular inflammation. Increased leukocyte-endothelial interaction is a hallmark of vascular inflammation. The nucleotide P2Y₂ receptor (P2Y₂R), activated by extracellular ATP≈UTP, plays a role in cardiovascular homeostasis and immune regulation. Moreover, accumulating evidence from studies in vitro and in vivo models have implicated the P2Y₂R in the inflammatory response significantly contributing to the progression and pathogenesis of asthma, atherosclerosis, sepsis, and ischemia. I hypothesized that P2Y₂R activation by UTP, an agonist of the receptor, increased leukocyte rolling and adhesion in the microvasculature from baseline. To test the hypothesis, …

Structural Basis For +1 Ribosomal Frameshifting During Ef-G-Catalyzed Translocation., Gabriel Demo, Howard Gamper, Anna B. Loveland, Isao Masuda, Christine E. Carbone, Egor Svidritskiy, Ya-Ming Hou, Andrei A. Korostelev

Department of Biochemistry and Molecular Biology Faculty Papers

Frameshifting of mRNA during translation provides a strategy to expand the coding repertoire of cells and viruses. How and where in the elongation cycle +1-frameshifting occurs remains poorly understood. We describe seven ~3.5-Å-resolution cryo-EM structures of 70S ribosome complexes, allowing visualization of elongation and translocation by the GTPase elongation factor G (EF-G). Four structures with a + 1-frameshifting-prone mRNA reveal that frameshifting takes place during translocation of tRNA and mRNA. Prior to EF-G binding, the pre-translocation complex features an in-frame tRNA-mRNA pairing in the A site. In the partially translocated structure with EF-G•GDPCP, the tRNA shifts to the +1-frame near …

Chloride Sensing By Wnk1 Regulates Nlrp3 Inflammasome Activation And Pyroptosis., Lindsey Mayes-Hopfinger, Aura Enache, Jian Xie, Chou-Long Huang, Robert Köchl, Victor L.J. Tybulewicz, Teresa Fernandes-Alnemri, Emad S. Alnemri

Department of Biochemistry and Molecular Biology Faculty Papers

The NLRP3 inflammasome mediates the production of proinflammatory cytokines and initiates inflammatory cell death. Although NLRP3 is essential for innate immunity, aberrant NLRP3 inflammasome activation contributes to a wide variety of inflammatory diseases. Understanding the pathways that control NLRP3 activation will help develop strategies to treat these diseases. Here we identify WNK1 as a negative regulator of the NLRP3 inflammasome. Macrophages deficient in WNK1 protein or kinase activity have increased NLRP3 activation and pyroptosis compared with control macrophages. Mice with conditional knockout of WNK1 in macrophages have increased IL-1β production in response to NLRP3 stimulation compared with control mice. Mechanistically, …