Medical Biochemistry Commons^™

Novel Combination Bmp7 And Hgf Gene Therapy Instigates Selective Myofibroblast Apoptosis And Reduces Corneal Haze In Vivo, Suneel Gupta, Michael K. Fink, Arkasubhra Ghosh, Ratnakar Tripathi, Prashant R. Sinha, Ajay Sharma, Nathan P. Hesemann, Shyam S. Chaurasia, Elizabeth A. Giuliano, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE. We tested the potential of bone morphogenic protein 7 (BMP7) and hepatocyte growth factor (HGF) combination gene therapy to treat preformed corneal fibrosis using established rabbit in vivo and human in vitro models.

METHODS. Eighteen New Zealand White rabbits were used. Corneal fibrosis was produced by alkali injury. Twenty-four hours after scar formation, cornea received topically either balanced salt solution (BSS; n ¼ 6), polyethylenimine-conjugated gold nanoparticle (PEI2-GNP)-naked plasmid (n ¼ 6) or PEI2-GNP plasmids expressing BMP7 and HGF genes (n ¼ 6). Donor human corneas were used to obtain primary human corneal fibroblasts and myofibroblasts for mechanistic studies. …

V-Atpase Roles In Prostate Cancer, Yamhilette Licon Munoz

Biomedical Sciences ETDs

Vacuolar ATPase (V-ATPase) is responsible for maintaining the acidic pH of the endomembrane system in eukaryotic cells. V-ATPase active transport of protons generates the differential luminal pH in lysosomes, endosomes, and the Golgi. In addition to intracellular V-ATPase, cancer cells have V-ATPase at the plasma membrane. Plasmalemmal V-ATPase acidifies the extracellular milieu and enhances cell motility and invasion, evidence that V-ATPase contributes to tumorigenic phenotypes. We studied V-ATPase cellular functions in prostate cancer (PCa), the most commonly diagnosed cancer for men in the United States. V-ATPase inhibitors decreased invasion and migration of PCa cells. In aggressive PCa cell lines, C4-2B …

Arylquinoline And Analog Compounds And Use Thereof To Treat Cancer, David S. Watt, Chunming Liu, Vivek M. Rangnekar, Vitaliy M. Sviripa, Ravshan Burikhanov, Wen Zhang

Molecular and Cellular Biochemistry Faculty Patents

The subject technology relates to arylquinoline compounds and their use for treating cancer or cancer metastasis. The compounds of the subject technology promote cells to secrete a pro-apoptotic tumor suppressor, i.e., prostate apoptosis response-4 (Par-4), which in turn promote apoptosis in cancer cells or metastatic cells.

Curcumin Potentiates The Function Of Human Α7-Nicotinic Acetylcholine Receptors Expressed In Sh-Ep1 Cells, Eslam El Nebrisi, Lina T. Al Kury, Keun-Hang Susan Yang, Petrilla Jayaprakash, Frank Christopher Howarth, Nadine Kabbani, Murat Oz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Effects of curcumin, a biologically active ingredient of turmeric, were tested on the Ca²⁺transients induced by the activation of α₇ subunit of the human nicotinic acetylcholine (α₇nACh) receptor expressed in SH-EP1 cells. Curcumin caused a significant potentiation of choline (1 mM)-induced Ca²⁺ transients with an EC₅₀ value of 133 nM. The potentiating effect of curcumin was not observed in Ca²⁺ transients induced by high K⁺ (60 mM) containing solutions or activation of α₄β₂ nACh receptors and the extent of curcumin potentiation was not altered in the presence of …

Sphingomyelin And Gm1 Influence Huntingtin Binding To, Disruption Of, And Aggregation On Lipid Membranes, Maxmore Chaibva, Xiang Gao, Pranav Jain, Warren A. Campbell, Shelli L. Frey, Justin Legleiter

Chemistry Faculty Publications

Huntington disease (HD) is an inherited neurodegenerative disease caused by the expansion beyond a critical threshold of a polyglutamine (polyQ) tract near the N-terminus of the huntingtin (htt) protein. Expanded polyQ promotes the formation of a variety of oligomeric and fibrillar aggregates of htt that accumulate into the hallmark proteinaceous inclusion bodies associated with HD. htt is also highly associated with numerous cellular and subcellular membranes that contain a variety of lipids. As lipid homeostasis and metabolism abnormalities are observed in HD patients, we investigated how varying both the sphingomyelin (SM) and ganglioside (GM1) contents modifies the interactions between htt …

Glia-To-Neuron Transfer Of Mirnas Via Extracellular Vesicles: A New Mechanism Underlying Inflammation-Induced Synaptic Alterations, Ilaria Prada, Martina Gabrielli, Elena Turola, Alessia Iorio, Giulia D'Arrigo, Roberta Parolisi, Mariacristina De Luca, Marco Pacifici, Mattia Bastoni, Marta Lombardi, Giuseppe Legname, Dan Cojoc, Annalisa Buffo, Roberto Furlan, Francesca Peruzzi, Claudia Verderio

School of Medicine Faculty Publications

Recent evidence indicates synaptic dysfunction as an early mechanism affected in neuroinflammatory diseases, such as multiple sclerosis, which are characterized by chronic microglia activation. However, the mode(s) of action of reactive microglia in causing synaptic defects are not fully understood. In this study, we show that inflammatory microglia produce extracellular vesicles (EVs) which are enriched in a set of miRNAs that regulate the expression of key synaptic proteins. Among them, miR-146a-5p, a microglia-specific miRNA not present in hippocampal neurons, controls the expression of presynaptic synaptotagmin1 (Syt1) and postsynaptic neuroligin1 (Nlg1), an adhesion protein which play a crucial role in dendritic …

Could A Common Mechanism Of Protein Degradation Impairment Underlie Many Neurodegenerative Diseases?, David M. Smith

Faculty & Staff Scholarship

At the cellular level, many neurodegenerative diseases (NDs), often considered proteinopathies, are characterized by the accumulation of misfolded and damaged proteins into large insoluble aggregates. Prominent species that accumulate early and play fundamental roles in disease pathogenesis are amyloid β (Aβ) and tau in Alzheimer disease, α-synuclein (α-syn) in Parkinson disease, and polyQ-expanded huntingtin (Htt) in Huntington disease. Although significant efforts have focused on how the cell deals with these protein aggregates, why is it that these misfolded proteins are not degraded normally in the first place? A vast body of literature supports the notion that the cell’s protein degradation …

Experimental Intravascular Hemolysis Induces Hemodynamic And Pathological Pulmonary Hypertension: Association With Accelerated Purine Metabolism, Victor P. Bilan, Frank Schneider, Enrico M. Novelli, Eric E. Kelley, Sruti Shiva, Mark T. Gladwin, Edwin K. Jackson, Stevan P. Tofovic

Faculty & Staff Scholarship

Pulmonary hypertension (PH) is emerging as a serious complication associated with hemolytic disorders, and plexiform lesions (PXL) have been reported in patients with sickle cell disease (SCD). We hypothesized that repetitive hemolysis per se induces PH and angioproliferative vasculopathy and evaluated a new mechanism for hemolysis-associated PH (HA-PH) that involves the release of adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) from erythrocytes. In healthy rats, repetitive admin- istration of hemolyzed autologous blood (HAB) for 10 days produced reversible pulmonary parenchymal injury and vascular remodeling and PH. Moreover, the combination of a single dose of Sugen-5416 (SU, 200mg/kg) and 10-day …

Conformational Switching In The Coiled-Coil Domains Of A Proteasomal Atpase Regulates Substrate Processing, Aaron Snoberger, Evan J. Brettrager, David M. Smith

Faculty & Staff Scholarship

Protein degradation in all domains of life requires ATPases that unfold and inject proteins into compartmentalized proteolytic chambers. Proteasomal ATPases in eukaryotes and archaea contain poorly understood N-terminally conserved coiled-coil domains. In this study, we engineer disulfide crosslinks in the coiled-coils of the archaeal proteasomal ATPase (PAN) and report that its three identical coiled-coil domains can adopt three different conforma- tions: (1) in-register and zipped, (2) in-register and partially unzipped, and (3) out-of-register. This conformational heterogeneity conflicts with PAN’s symmetrical OB-coiled-coil crystal structure but resembles the conformational heterogeneity of the 26S proteasomal ATPases’ coiled-coils. Furthermore, we find that one coiled-coil …

A Common Mechanism Of Proteasome Impairment By Neurodegenerative Disease-Associated Oligomers, Tiffany A. Thibaudeau, Raymond T. Anderson, David M. Smith

Faculty & Staff Scholarship

Protein accumulation and aggregation with a concomitant loss of proteostasis often con- tribute to neurodegenerative diseases, and the ubiquitin–proteasome system plays a major role in protein degradation and proteostasis. Here, we show that three different proteins from Alzheimer’s, Parkinson’s, and Huntington’s disease that misfold and oligomerize into a shared three-dimensional structure potently impair the proteasome. This study indicates that the shared conformation allows these oligomers to bind and inhibit the proteasome with low nanomolar affinity, impairing ubiquitin-dependent and ubiquitin-independent proteasome function in brain lysates. Detailed mechanistic analysis demonstrates that these oligomers inhibit the 20S proteasome through allosteric impairment of the …

Reducing Discard Blood Draw Volumes From Subcutaneously Implanted Ports (Port) In Patients With End Stage Renal Disease (Esrd), Uttam Garg, Tyson Moore, Renita Trujillo, Penny Monachino, Amy Wiebold, Angela Ferguson, Gabor Oroszi, Vimal Chadha

Posters

Background
•To monitor clinical status, dialysis and transplant patients with ESRD frequently require blood draws.
•To preserve their veins and to avoid frequent intravenous access, these patients, especially young children, require PORT placement.
•The PORT is flushed with saline and filled with heparinized saline to prevent blood clotting between blood draws.
•To avoid contamination from PORT fluids, a fixed amount of blood is withdrawn and discarded before the blood sample is drawn for laboratory analyses. Currently, the recommended discard blood volume is 5 mL (five times the reservoir volume of most PORTs and attached catheters.)
•The volume of discarded blood …

Inactivation Of Endoplasmic Reticulum Stress And The Prevention Of Neurodegenerative Diseases, Ian James Martins

Research outputs 2014 to 2021

Biotherapeutics and nutritional therapy are essential for the treatment of endoplasmic reticulum (ER) stress in diabetes and neurodegenerative diseases. Oxidative stress and nutrient excess may induce ER stress associated with activation of the unfolded protein response and connected to cell death. The heat shock gene Sirtuin 1 (Sirt 1) is important to the heat shock response with amyloid beta aggregation associated with the induction of mitophagy and ER stress in neuron cells. Genomic medicine that activates nuclear Sirt 1 is essential for the prevention of mitochondrial apoptosis and ER stress. Inhibitors such as drugs, alcohol, excess caffeine and palmitic acid …

Rpe Vs. Percentage 1rm Loading In Periodized Programs Matched For Sets And Repetitions, Eric R. Helms, Ryan K. Byrnes, Daniel M. Cooke, Michael H. Haischer, Joseph P. Carzoli, Trevor K. Johnson, Matt R. Cross, John B. Cronin, Adam G. Storey, Michael C. Zourdos

Research outputs 2014 to 2021

Purpose: To investigate differences between rating of perceived exertion (RPE) and percentage one-repetition maximum (1RM) load assignment in resistance-trained males (19-35 years) performing protocols with matched sets and repetitions differentiated by load-assignment. Methods: Participants performed squats then bench press 3x/weeks in a daily undulating format over 8-weeks. Participants were counterbalanced by pre-test 1RM then assigned to percentage 1RM (1RMG, n = 11); load-assignment via percentage 1RMs, or RPE groups (RPEG, n = 10); participant-selected loads to reach target RPE ranges. Ultrasonography determined pre and post-test pectoralis (PMT), and vastus lateralis muscle thickness at 50 (VLMT50) and 70% (VLMT70) femur-length. Results: …

Saturation Mutagenesis Reveals Manifold Determinants Of Exon Definition., Shengdong Ke, Vincent Anquetil, Jorge Rojas Zamalloa, Alisha Maity, Anthony Yang, Mauricio A. Arias, Sergey Kalachikov, James J Russo, Jingyue Ju, Lawrence A. Chasin

Student Papers, Posters & Projects

To illuminate the extent and roles of exonic sequences in the splicing of human RNA transcripts, we conducted saturation mutagenesis of a 51-nt internal exon in a three-exon minigene. All possible single and tandem dinucleotide substitutions were surveyed. Using high-throughput genetics, 5560 minigene molecules were assayed for splicing in human HEK293 cells. Up to 70% of mutations produced substantial (greater than twofold) phenotypes of either increased or decreased splicing. Of all predicted secondary structural elements, only a single 15-nt stem-loop showed a strong correlation with splicing, acting negatively. The in vitro formation of exon-protein complexes between the mutant molecules and …

Significant Loss Of Blood Amino Acids And Free Carnitine In Newborns Receiving Continuous Renal Replacement Therapy (Crrt), Uttam Garg, Marita Thompson, Bradley A. Warady, Vimal Chadha

Posters

Background

•Newborns with acute kidney injury (AKI) or end-stage kidney disease (ESKD) often receive prolonged CRRT when the early initiation of peritoneal dialysis is either contraindicated or unable to be performed. •These patients often receive total parenteral nutrition (TPN) to meet their nutritional goals. •Little to no information exists on the loss of blood amino acids (AA) and carnitine during CRRT in these patients. •The objective of this study was to determine the amino acids and carnitine losses in newborns receiving prolonged CRRT and TPN. Material and Methods

•Three newborns who received prolonged (> 2 weeks) CRRT and TPN were …

Effect Of Hemiepiphysiodesis On The Growth Plate: The Histopathological Changes And Mechanism Exploration Of Recurrence In Mini Pig Model., Jing Ding, Jin He, Zhi-Qiang Zhang, Zhen-Kai Wu, Fang-Chun Jin

Manuscripts, Articles, Book Chapters and Other Papers

Purpose: Hemiepiphysiodesis has been widely used to correct angular deformity of long bone in immature patients. However, there is a limited knowledge about the biomechanical effect of this technique on the histopathological changes of the growth plate and the mechanism of recurrence of malformation after implant removal. We aimed to evaluate the biomechanical effect of hemiepiphysiodesis on the histopathological changes of the growth plate and the mechanism of recurrence of malformation after implant removal in Bama miniature pigs, and to explore the role of asymmetric stress during this procedure.

Methods: Eight 3-month-old male Bama miniature pigs sustained surgeries on the …

Effect Of Metformin Exposure On Growth And Photosynthetic Performance In The Unicellular Freshwater Chlorophyte, Chlorella Vulgaris, Brittany M. Cummings, Joseph A. Needoba, Tawnya D. Peterson

OHSU-PSU School of Public Health Faculty Publications and Presentations

Many pharmaceuticals have negative effects on biota when released into the environment. For example, recent work has shown that the commonly prescribed antidiabetic drug, metformin (N,N-dimethylbiguanide), has endocrine disrupting effects on fish. However, effects of metformin on aquatic primary producers are poorly known. We exposed cultured isolates of a freshwater chlorophyte, Chlorella vulgaris, to a range of metformin concentrations (0– 767.9 mg L-1) to test the hypothesis that exposure negatively affects photosynthesis and growth. A cessation of growth, increase in non-photochemical quenching (NPQ, NPQmax), and reduced electron transport rate (ETR) were observed 24 h after exposure to a metformin concentration …

Targeting Ovarian Cancer And Endothelium With An Allosteric Ptp4a3 Phosphatase Inhibitor, Kelley E. Mcqueeney, Joseph M. Salamoun, James C. Burnett, Nektarios Barabutis, Paula Pekic, Sophie L. Lewandowski, Danielle C. Llaneza, Robert Cornelison, Yunpeng Bai, Zhong-Yin Zhang, John D. Catravas

Bioelectrics Publications

Overexpression of protein tyrosine phosphatase PTP4A oncoproteins is common in many human cancers and is associated with poor patient prognosis and survival. We observed elevated levels of PTP4A3 phosphatase in 79% of human ovarian tumor samples, with significant overexpression in tumor endothelium and pericytes. Furthermore, PTP4A phosphatases appear to regulate several key malignant processes, such as invasion, migration, and angiogenesis, suggesting a pivotal regulatory role in cancer and endothelial signaling pathways. While phosphatases are attractive therapeutic targets, they have been poorly investigated because of a lack of potent and selective chemical probes. In this study, we disclose that a potent, …

Cone Phosphodiesterase-6Γ’ Subunit Augments Cone Pde6 Holoenzyme Assembly And Stability In A Mouse Model Lacking Both Rod And Cone Pde6 Catalytic Subunits, Wen-Tao Deng, Saravanan Kolandaivelu, Astra Dinculescu, Jie Li, Ping Zhu, Vince A. Chiodo, Visvanathan Ramamurthy, William W. Hauswirth

Faculty & Staff Scholarship

Rod and cone phosphodiesterase 6 (PDE6) are key effector enzymes of the vertebrate phototransduction pathway. Rod PDE6 consists of two catalytic subunits PDE6α and PDE6β and two identical inhibitory PDE6γ subunits, while cone PDE6 is composed of two identical PDE6α’ catalytic subunits and two identical cone-specific PDE6γ’ inhibitory subunits. Despite their prominent function in regulating cGMP levels and therefore rod and cone light response properties, it is not known how each subunit contributes to the functional differences between rods and cones. In this study, we generated an rd10/cpfl1 mouse model lacking rod PDE6β and cone PDE6α’ subunits. Both rod and …

Characterization Of Cdk(5) Inhibitor, 20-223 (Aka Cp668863) For Colorectal Cancer Therapy, Caroline M. Robb, Smit Kour, Jacob I. Contreras, Ekta Agarwal, Carter J. Barger, Sandeep Rana, Yogesh Sonawane, Beth K. Neilsen, Margaret Taylor, Smitha Kizhake, Rhishikesh N. Thakare, Sanjib Chowdhury, Jing Wang, Jennifer D. Black, Michael A. Hollingsworth, Michael G. Brattain, Amarnath Natarajan

Journal Articles: Biochemistry & Molecular Biology

Colorectal cancer (CRC) remains one of the leading causes of cancer related deaths in the United States. Currently, there are limited therapeutic options for patients suffering from CRC, none of which focus on the cell signaling mechanisms controlled by the popular kinase family, cyclin dependent kinases (CDKs). Here we evaluate a Pfizer developed compound, CP668863, that inhibits cyclin-dependent kinase 5 (CDK5) in neurodegenerative disorders. CDK5 has been implicated in a number of cancers, most recently as an oncogene in colorectal cancers. Our lab synthesized and characterized CP668863 – now called 20-223. In our established colorectal cancer xenograft model, 20-223 reduced …

Pancreatic Cancer Associated With Obesity And Diabetes: An Alternative Approach For Its Targeting, Ramesh Pothuraju, Satyanarayana Rachagani, Wade M. Junker, Sanjib Chaudhary, Saraswathi Viswanathan, Sukhwinder Kaur, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Pancreatic cancer (PC) is among foremost causes of cancer related deaths worldwide due to generic symptoms, lack of effective screening strategies and resistance to chemo- and radiotherapies. The risk factors associated with PC include several metabolic disorders such as obesity, insulin resistance and type 2 diabetes mellitus (T2DM). Studies have shown that obesity and T2DM are associated with PC pathogenesis; however, their role in PC initiation and development remains obscure.

MAIN BODY: Several biochemical and physiological factors associated with obesity and/or T2DM including adipokines, inflammatory mediators, and altered microbiome are involved in PC progression and metastasis albeit by different …

Systems Biology Of Human Cells Responded To Influenza B Virus Infection, Kritsada Sirivassanametha

Chulalongkorn University Theses and Dissertations (Chula ETD)

Influenza B virus is a member of Orthomyxoviridae family which can cause influenza in human and affect to worldwide health problem. Systems biology is the computational modeling of molecular systems which is useful to predict how these biological systems change over time and under different conditions. In this study the multiomics was used to study human cellular response to influenza B virus infection. The transcriptome including mRNAs, lncRNAs and miRNAs and proteome were investigated by high-throughput technologies such as next-generation sequencing and mass spectrometry. The results showed that in human cells infected with influenza B virus, transcriptome including mRNAs, lncRNAs …

Alternative Splicing Of Cytoplasmic Polyadenylation Element Binding Protein 2 Is Modulated Via Serine Arginine Splicing Factor 3 In Cancer Metastasis, James T. Deligio, James Thomas Deligio

Theses and Dissertations

Our laboratory delineated a role for alternative pre-mRNA splicing (AS) in triple negative breast cancer (TNBC). We found the translational regulator cytosolic polyadenylation element binding protein 2 (CPEB2) which has two isoforms, CPEB2A and CPEB2B, is alternatively spliced during acquisition of anoikis resistance (AnR) and metastasis. The splicing event which determines the CPEB2 isoform is via inclusion/ exclusion of exon four in the mature mRNA transcript. The loss of CPEB2A with a concomitant increase in CPEB2B is required for TNBC cells to metastasize in vivo. We examined RNAseq profiles of TNBC cells which had CPEB2 isoforms specifically downregulated to …

B-Cell Activating Factor As An Immunological Marker Of Disease Outcome And Treatment Response In Patients With Chronic Hepatitis B Virus Infection, Apichaya Khlaiphuengsin

Chulalongkorn University Theses and Dissertations (Chula ETD)

B-cell activating factor (BAFF), an important cytokine for B lymphocyte activation that implicated in the pathogenesis and disease progression chronic hepatitis B (CHB) patients. This study aimed at evaluating clinical correlation and prognostic role of plasma BAFF, BAFF receptor and related polymorphisms in patients with CHB undergoing pegylated interferon (peg-IFN) treatment and HBV-related hepatocellular carcinoma (HCC). This study shown that BAFF levels were elevated during treatment but decreased to pre-treatment levels after peg-IFN cessation in HBeAg-positive CHB patients. Patients with HCC had significantly higher BAFF levels compared with the non-HCC group and healthy controls. Moreover, the frequency of rs9514828 CT+TT …

The Effect Of Dna Methylation On Tp73 Expression In Tumorgenesis, Nujuma A. Moussa

UROP Posters

Abstract: The Effect of DNA Methylation on TP73 Expression in Tumorgenesis

Nujuma Moussa, Zhixing Yao, Zaki A. Sherif

Department of Biochemistry & Molecular Biology, Howard University College of Medicine

TP73 is a member of the TP53 family of proteins that acts as a transcription factor to help regulate cellular distress. This tumor protein may play a dual role as a tumor suppressor and tumor promoter. The TP73 gene is mapped to chromosome 1p36, a frequently deleted region in neuroblastoma and other types of tumors. While mutations in the TP53 gene are commonly known to cause noxious cancers, 30% of cancers …

Understanding The Role Of Phosphoinositide 3-Kinase And Its Function As A Driving Force Behind The Er Stress Response In Fibrostenotic Crohn’S Disease-Affected Ileal Smooth Muscle Cells, Prashant Yadav

Theses and Dissertations

Crohn’s disease (CD) affects about 780,000 people in the United States alone, and it is estimated that 6-15 per 100,000 persons will receive a diagnosis of this disease each year. There currently is no cure for Crohn’s disease, and available medical therapies simply serve to alleviate the inflammation. This does not help treat fibrostenosis that Crohn’s disease patients may develop, which can only be treated surgically. Finding alternatives to treat CD requires an understanding of mechanisms at the biochemical level. In this thesis, we attempted to gain a better understanding of certain pathways found to be active in Crohn’s disease-affected …

Plasma Medicine: A Brief Introduction, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

This mini review is to introduce the readers of Plasma to the field of plasma medicine. This is a multidisciplinary field of research at the intersection of physics, engineering, biology and medicine. Plasma medicine is only about two decades old, but the research community active in this emerging field has grown tremendously in the last few years. Today, research is being conducted on a number of applications including wound healing and cancer treatment. Although a lot of knowledge has been created and our understanding of the fundamental mechanisms that play important roles in the interaction between low temperature plasma and …

Three-Dimensional Context Rather Than Nls Amino Acid Sequence Determines Importin Α Subtype Specificity For Rcc1., Rajeshwer S. Sankhala, Ravi K. Lokareddy, Salma Begum, Ruth A. Pumroy, Richard E. Gillilan, Gino Cingolani

Department of Biochemistry and Molecular Biology Faculty Papers

Active nuclear import of Ran exchange factor RCC1 is mediated by importin α3. This pathway is essential to generate a gradient of RanGTP on chromatin that directs nucleocytoplasmic transport, mitotic spindle assembly and nuclear envelope formation. Here we identify the mechanisms of importin α3 selectivity for RCC1. We find this isoform binds RCC1 with one order of magnitude higher affinity than the generic importin α1, although the two isoforms share an identical NLS-binding groove. Importin α3 uses its greater conformational flexibility to wedge the RCC1 β-propeller flanking the NLS against its lateral surface, preventing steric clashes with its Armadillo-core. Removing …

Synergy Of Two Low-Affinity Nlss Determines The High Avidity Of Influenza A Virus Nucleoprotein Np For Human Importin Α Isoforms., Wei Wu, Rajeshwer S. Sankhala, Tyler J Florio, Lixin Zhou, Nhan L.T. Nguyen, Ravi K. Lokareddy, Gino Cingolani, Nelly Panté

Department of Biochemistry and Molecular Biology Faculty Papers

The influenza A virus nucleoprotein (NP) is an essential multifunctional protein that encapsidates the viral genome and functions as an adapter between the virus and the host cell machinery. NPs from all strains of influenza A viruses contain two nuclear localization signals (NLSs): a well-studied monopartite NLS1 and a less-characterized NLS2, thought to be bipartite. Through site-directed mutagenesis and functional analysis, we found that NLS2 is also monopartite and is indispensable for viral infection. Atomic structures of importin α bound to two variants of NLS2 revealed NLS2 primarily binds the major-NLS binding site of importin α, unlike NLS1 that associates …

Pitx3null Mutant (Striatal Dopamine-Deficient) Mice Have Exaggerated Spiny Projection Neuron Responses To L-Dopa And D1 Agonism And Lack Baseline Striatonigral Spiking, Ben Sagot

Theses and Dissertations (ETD)

L-3,4 dihidroxyphenylalanine (l-DOPA) strongly stimulates motor activity in parkinsonian patients and animal models of Parkinson's disease. Severe striatal dopamine (DA) loss characterizes Parkinson's disease and its animal models. Given the canonical rate model of Parkinson's Disease pathophysiology based on differences in DA pharmacology manifesting as electrophysiological differences in striatal projection neuron (SPN) spike rates, SPNs should increase spiking during the motor response to l-DOPA. In fact, stimulating specific subsets of these neurons to spike in freely-moving wild type and parkinsonian animals causes or inhibits motor activity as predicted. However, pharmacological effects of DA deficiency, let alone those of DA replacement, …