Structural And Thermodynamic Basis Of Amprenavir/Darunavir And Atazanavir Resistance In Hiv-1 Protease With Mutations At Residue 50,
2013
University of Massachusetts Medical School
Structural And Thermodynamic Basis Of Amprenavir/Darunavir And Atazanavir Resistance In Hiv-1 Protease With Mutations At Residue 50, Seema Mittal, Rajintha Bandaranayake, Nancy King, Moses Prabu-Jeyabalan, Madhavi Nalam, Ellen Nalivaika, Nese Yilmaz, Celia Schiffer
Celia A. Schiffer
Drug resistance occurs through a series of subtle changes that maintain substrate recognition but no longer permit inhibitor binding. In HIV-1 protease, mutations at I50 are associated with such subtle changes that confer differential resistance to specific inhibitors. Residue I50 is located at the protease flap tips, closing the active site upon ligand binding. Under selective drug pressure, I50V/L substitutions emerge in patients, compromising drug susceptibility and leading to treatment failure. The I50V substitution is often associated with amprenavir (APV) and darunavir (DRV) resistance, while the I50L substitution is observed in patients failing atazanavir (ATV) therapy. To explain how APV, …
Dna Homologous Recombination Factor Sfr1 Physically And Functionally Interacts With Estrogen Receptor Alpha,
2013
Cincinnati Children's Hospital Medical Center
Dna Homologous Recombination Factor Sfr1 Physically And Functionally Interacts With Estrogen Receptor Alpha, Yuxin Feng, David Singleton, Chun Guo, Amanda Gardner, Suresh Pakala, Rakesh Kumar, Elwood Jensen, Jinsong Zhang, Sohaib Khan
Biochemistry and Molecular Medicine Faculty Publications
Estrogen receptor alpha (ERα), a ligand-dependent transcription factor, mediates the expression of its target genes by interacting with corepressors and coactivators. Since the first cloning of SRC1, more than 280 nuclear receptor cofactors have been identified, which orchestrate target gene transcription. Aberrant activity of ER or its accessory proteins results in a number of diseases including breast cancer. Here we identified SFR1, a protein involved in DNA homologous recombination, as a novel binding partner of ERα. Initially isolated in a yeast two-hybrid screen, the interaction of SFR1 and ERα was confirmed in vivo by immunoprecipitation and mammalian one-hybrid assays. SFR1 …
Developmental Signaling Requires Inwardly Rectifying K+ Channels In Drosophila Melanogaster,
2013
Brigham Young University - Provo
Developmental Signaling Requires Inwardly Rectifying K+ Channels In Drosophila Melanogaster, Giri Raj Dahal
Theses and Dissertations
Inwardly rectifying potassium (IRK/Kir) channels regulate intracellular K+ concentrations and membrane potential. Disruption of Kir2.1 causes dominantly inherited Andersen Tawil Syndrome (ATS). ATS patients suffer from cardiac arrhythmias, periodic paralysis, and cognitive impairment. These symptoms are consistent with current understanding of the role of ion channels in muscle cells and neurons. However, ATS symptoms also include craniofacial and digital deformities such as cleft palate, dental defects, wide set eyes, low set ears, and crooked or fused digits. These developmental defects were not consistent with current understanding of developmental signaling or previously described roles for ion channels. We found that phenotypes …
Identification Of Cyclophilin Gene Family In Soybean And Characterization Of Gmcyp1,
2013
The University of Western Ontario
Identification Of Cyclophilin Gene Family In Soybean And Characterization Of Gmcyp1, Hemanta Raj Mainali
Electronic Thesis and Dissertation Repository
I identified members of the Cyclophilin (CYP) gene family in soybean (Glycine max) and characterized the GmCYP1, one of the members of soybean CYP. CYPs belong to the immunophilin superfamily with peptidyl-prolyl cis-trans isomerase (PPIase) activity. PPIase catalyzes the interconversion of the cis- and trans-rotamers of the peptidyl-prolyl amide bond of peptides. After extensive data mining, I identified 62 different CYP genes in soybean (GmCYP1 to GmCYP62), of which 8 are multi-domain proteins and 54 are single domain proteins. At least 25% of the GmCYP genes are expressed in soybean. GmCYP1 …
The Role Of Smpb In Licensing Tmrna Entry Into Stalled Ribosomes,
2013
Brigham Young University - Provo
The Role Of Smpb In Licensing Tmrna Entry Into Stalled Ribosomes, Mickey R. Miller
Theses and Dissertations
Ribosomes translate the genetic information contained in mRNAs into protein by linking together amino acids with the help of aminoacyl-tRNAs. In bacteria, protein synthesis stalls when the ribosome reaches the 3'-end of truncated mRNA transcripts lacking a stop codon. Trans-translation is a conserved bacterial quality control process that rescues stalled ribosomes. Transfer-messenger RNA (tmRNA) and its protein partner SmpB mimic a tRNA by entering the A site of the ribosome and accepting the growing peptide chain. The ribosome releases the truncated mRNA and resumes translation on the tmRNA template. The open reading frame found on tmRNA encodes a peptide tag …
Heterogeneous Nuclear Ribonucleoprotein K Supports Vesicular
Stomatitis Virus Replication By Regulating Cell Survival And Cellular
Gene Expression,
2013
University of Nebraska-Lincoln
Heterogeneous Nuclear Ribonucleoprotein K Supports Vesicular Stomatitis Virus Replication By Regulating Cell Survival And Cellular Gene Expression, Phat X. Dinh, Anshuman Das, Rodrigo Franco, Asit K. Pattnaik
School of Veterinary and Biomedical Sciences: Faculty Publications
The heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a member of the family of hnRNPs and was recently shown in a genome-wide small interfering RNA (siRNA) screen to support vesicular stomatitis virus (VSV) growth. To decipher the role of hnRNP K in VSV infection, we conducted studies which suggest that the protein is required for VSV spreading. Virus binding to cells, entry, and nucleocapsid uncoating steps were not adversely affected in the absence of hnRNP K, whereas viral genome transcription and replication were reduced slightly. These results indicate that hnRNP K is likely involved in virus assembly and/or release from …
Purification And Characterization Of Enzymes From Yeast: An Extended Undergraduate Laboratory Sequence For Large Classes,
2013
Xavier University of Louisiana
Purification And Characterization Of Enzymes From Yeast: An Extended Undergraduate Laboratory Sequence For Large Classes, Kelly E. Johanson, Terry J. Watt, Neil R. Mcintyre, Marleesa Thompson
Faculty and Staff Publications
Providing a project-based experience in an undergraduate biochemistry laboratory class can be complex with large class sizes and limited resources. We have designed a 6-week curriculum during which students purify and characterize the enzymes invertase and phosphatase from bakers yeast. Purification is performed in two stages via ethanol precipitation and anion exchange chromatography, and students perform both direct and coupled enzyme assays. By completion of the experimental series, students are able to identify which enzymes they have purified and have obtained kinetic parameters for one. This experimental series requires minimal instructor preparation time, is cost effective, and works with multiple …
Immunomodulatory Activity Of Sambucus Mexicana And Trichostema Lanatum On Lps Stimulated Raw 264.7 Macrophage Cells,
2013
Pepperdine University
Immunomodulatory Activity Of Sambucus Mexicana And Trichostema Lanatum On Lps Stimulated Raw 264.7 Macrophage Cells, Victoria Hester, P. Matthew Joyner
Featured Research
Chumash medicinal plants Sambucus mexicana (Mexican elderberry) and Trichostema lanatum (woolly blue curls) were tested for immunomodulatory activity. Anti-inflammatory effects were determined by treating LPS induced RAW 264.7 macrophage cells with plant extracts and measuring the levels of cytokines: tumor necrosis factor alpha (TNF-alpha) and interleukin 10 (IL-10). We hypothesized that both plants would exert immunomodulatory activity by reducing the pro-inflammatory production of TNF-alpha or by promoting M2 polarization with a concurrent increase in IL-10 production. At concentration 0.01 mg/mL woolly blue curls and Mexican elderberry demonstrated anti-inflammatory activity by reducing the concentration of TNF-alpha in vitro, while levels of …
An Ethnobotanical Approach To Finding Antimicrobial Compounds In Wooly Blue Curls (Trichostema Lanatum) Using A Kirby-Bauer Disc Diffusion Assay,
2013
Pepperdine University
An Ethnobotanical Approach To Finding Antimicrobial Compounds In Wooly Blue Curls (Trichostema Lanatum) Using A Kirby-Bauer Disc Diffusion Assay, Matthew C. Fleming, P. Matthew Joyner
Featured Research
Plants can be an important source of creativity and production of new drugs. In this study, extracts of wooly blue curls (Trichostema lanatum) were made using DMSO and tested for antimicrobial activity on a panel of bacteria commonly found in separate ecological niches. Wooly blue curls (WBC) was chosen due to its being recorded as a strong disinfectant by the Chumash people. It was found that WBC does exhibit antimicrobial activity against gram positive bacteria and not against gram negative bacteria. However, gram negative bacteria with reduced drug efflux function became susceptible to the WBC extract.
Role Of Nucleation In Cortical Microtubule Array Organization: Variations On A Theme,
2013
Washington University in St Louis
Role Of Nucleation In Cortical Microtubule Array Organization: Variations On A Theme, Erica A. Fishel, Ram Dixit
Biology Faculty Publications & Presentations
The interphase cortical microtubules (CMTs) of plant cells form strikingly ordered arrays in the absence of a dedicated microtubule-organizing center. Considerable research effort has focused on activities such as bundling and severing that occur after CMT nucleation and are thought to be important for generating and maintaining ordered arrays. In this review, we focus on how nucleation affects CMT array organization. The bulk of CMTs are initiated from γ-tubulin-containing nucleation complexes localized to the lateral walls of pre-existing CMTs. These CMTs grow either at an acute angle or parallel to the pre-existing CMT. Although the impact of microtubule-dependent nucleation is …
New Types Of Morpho-Physiological Changes In Cells Exposed To Nanosecond Pulsed Electric Field,
2013
Old Dominion University
New Types Of Morpho-Physiological Changes In Cells Exposed To Nanosecond Pulsed Electric Field, Mikhail A. Rassokhin
Theses and Dissertations in Biomedical Sciences
Exposure of cells to a pulsed electric field (PEF) is the basis of multiple techniques and treatments. Nanosecond pulsed electric field (nsPEF) poses unique characteristics to induce subtle cellular effects while preserving cell integrity. Improving understanding of the mechanisms triggered by nsPEF in cells inspires new applications for the nanosecond pulse technology. Although many effects of nsPEF remain unknown, they can be inferred from morpho-physiologic changes, or cell reshaping, that accompany nsPEF exposure. During the exposure cells undergo reshaping that is manifested in swelling and diffuse blebbing. Recently we identified two new distinct forms of reshaping, pseudopod-like blebbing and microvesiculation, …
Carcinogenic Adducts Induce Distinct Dna Polymerase Binding Orientations,
2013
Wayne State University
Carcinogenic Adducts Induce Distinct Dna Polymerase Binding Orientations, Kyle B. Vrtis, Radoslaw P. Markiewicz, Louis J. Romano, David Rueda
Chemistry Faculty Research Publications
DNA polymerases must accurately replicate DNA to maintain genome integrity. Carcinogenic adducts, such as 2-aminofluorene (AF) and N-acetyl-2-aminofluorene (AAF), covalently bind DNA bases and promote mutagenesis near the adduct site. The mechanism by which carcinogenic adducts inhibit DNA synthesis and cause mutagenesis remains unclear. Here, we measure interactions between a DNA polymerase and carcinogenic DNA adducts in real-time by single-molecule fluorescence. We find the degree to which an adduct affects polymerase binding to the DNA depends on the adduct location with respect to the primer terminus, the adduct structure and the nucleotides present in the solution. Not only do the …
Investigation Of Water-Molecule Complexes And Their Catalytic Effect On Important Atmospheric Reactions,
2013
Brigham Young University - Provo
Investigation Of Water-Molecule Complexes And Their Catalytic Effect On Important Atmospheric Reactions, Taylor Scott Cline
Theses and Dissertations
This dissertation is a collection of works that investigates issues related to environmental chemistry. The first portion of this research explores the role of water vapor on the kinetics of important atmospheric reactions. Work is presented on the self-reaction of β-hydroxyethyl peroxy radical (β-HEP) and the catalytic increase in reaction rate by water vapor. β-HEP serves as a model system for investigating the possible role of water vapor in perturbing the kinetics and product branching ratio of atmospheric reactions of other alkyl peroxy radicals. The self-reaction rate coefficient of β-HEP was investigated between 276-296 K with 1.0 × 10^15 to …
A Novel Stratification Method In Linkage Studies To Address Inter- And Intra-Family Heterogeneity In Autism,
2013
University of Missouri-Kansas City School of Medicine
A Novel Stratification Method In Linkage Studies To Address Inter- And Intra-Family Heterogeneity In Autism, Zohreh Talebizadeh, Dan E. Arking, Valerie Wailin Hu
Biochemistry and Molecular Medicine Faculty Publications
Most genome linkage scans for autism spectrum disorders (ASDs) have failed to be replicated. Recently, a new ASD phenotypic sub-classification method was developed which employed cluster analyses of severity scores from the Autism Diagnostic Interview-Revised (ADI-R). Here, we performed linkage analysis for each of the four identified ADI-R stratified subgroups. Additional stratification was also applied to reduce intra-family heterogeneity and to investigate the impact of gender. For the purpose of replication, two independent sets of single nucleotide polymorphism markers for 392 families were used in our study. This deep subject stratification protocol resulted in 16 distinct group-specific datasets for linkage …
Human Adenovirus E1a Binds And Retasks Cellular Hbre1, Blocking Interferon Signalling And Activating Virus Early Gene Transcription,
2013
The University of Western Ontario
Human Adenovirus E1a Binds And Retasks Cellular Hbre1, Blocking Interferon Signalling And Activating Virus Early Gene Transcription, Gregory J. Fonseca
Electronic Thesis and Dissertation Repository
Upon infection, human adenovirus (HAdV) must block interferon signaling and activate the expression of its early genes to reprogram the cellular environment to support virus replication. During the initial phase of infection, these processes are orchestrated by the first HAdV gene expressed during infection, early region 1A (E1A). E1A binds and appropriates components of the cellular transcriptional machinery to modulate cellular gene transcription and activate viral early genes transcription. We have identified hBre1/RNF20 as a novel target of E1A. hBre1 is an E3 ubiquitin ligase which acts with the Ube2b E2 conjugase and accessory factors RNF40 and WAC1 to monoubiquitinate …
Identification Of Multiple Levels Of Trauma Induced Coagulopathy,
2013
Virginia Commonwealth University
Identification Of Multiple Levels Of Trauma Induced Coagulopathy, Jason Newton
Theses and Dissertations
Trauma continues to be a major cause of death across the globe. While the exact causes of trauma differ greatly between the military and civilian lifestyles, the ability to stop bleeding after trauma is paramount for survival. Over the past decade coagulation research has transitioned from a classical understanding of plasma based protein coagulation to the current cell focused research. As part of this shift, platelets have become a central player in hemostasis. Unfortunately little is currently understood about how platelet function is affected by trauma. In an effort to better define platelet function during trauma and the resulting shock …
Crystal Structure Of The Dna Cytosine Deaminase Apobec3f: The Catalytically Active And Hiv-1 Vif-Binding Domain,
2013
University of Massachusetts Medical School
Crystal Structure Of The Dna Cytosine Deaminase Apobec3f: The Catalytically Active And Hiv-1 Vif-Binding Domain, Markus-Frederik Bohn, Shivender Shandilya, John Albin, Takahide Kouno, Brett Anderson, Rebecca Mcdougle, Michael Carpenter, Anurag Rathore, Leah Evans, Ahkillah Davis, Jingying Zhang, Yongjian Lu, Mohan Somasundaran, Hiroshi Matsuo, Reuben Harris, Celia Schiffer
Celia A. Schiffer
Human APOBEC3F is an antiretroviral single-strand DNA cytosine deaminase, susceptible to degradation by the HIV-1 protein Vif. In this study the crystal structure of the HIV Vif binding, catalytically active, C-terminal domain of APOBEC3F (A3F-CTD) was determined. The A3F-CTD shares structural motifs with portions of APOBEC3G-CTD, APOBEC3C, and APOBEC2. Residues identified to be critical for Vif-dependent degradation of APOBEC3F all fit within a predominantly negatively charged contiguous region on the surface of A3F-CTD. Specific sequence motifs, previously shown to play a role in Vif susceptibility and virion encapsidation, are conserved across APOBEC3s and between APOBEC3s and HIV-1 Vif. In this …
Functional Integration Of The Conserved Domains Of Shoc2 Scaffold,
2013
University of Kentucky
Functional Integration Of The Conserved Domains Of Shoc2 Scaffold, Myoungkun Jeoung, Lina Abdelmoti, Eun Ryoung Jang, Craig W. Vander Kooi, Emilia Galperin
Molecular and Cellular Biochemistry Faculty Publications
Shoc2 is a positive regulator of signaling to extracellular signal-regulated protein kinases 1 and 2 (ERK1/2). Shoc2 is also proposed to interact with RAS and Raf-1 in order to accelerate ERK1/2 activity. To understand the mechanisms by which Shoc2 regulates ERK1/2 activation by the epidermal growth factor receptor (EGFR), we dissected the role of Shoc2 structural domains in binding to its signaling partners and its role in regulating ERK1/2 activity. Shoc2 is comprised of two main domains: the 21 leucine rich repeats (LRRs) core and the N-terminal non-LRR domain. We demonstrated that the N-terminal domain mediates Shoc2 binding to both …
Structure Of C-Terminal Domain Of Parkin, Ibr-Ring2,
2013
The University of Western Ontario
Structure Of C-Terminal Domain Of Parkin, Ibr-Ring2, Yeong Ju Noh
Electronic Thesis and Dissertation Repository
Parkin is an E3 ubiquitin ligase which degrades misfolded proteins and prevents the formation of abnormal protein aggregates often formed in Parkinson’s disease. The main goal of this thesis was to perform structural analysis on the IBR(In-Between-RING)-RING2 (Really Interesting New Gene) domain of parkin. After determining the three-dimensional solution structure of the protein by NMR spectroscopy, the RING2 domain was identified to be similar to the IBR domain, showing that it is not a canonical RING domain. The catalytic cysteine on RING2 was also shown to be solvent exposed, supporting the recently proposed RING/HECT hybrid mechanism of parkin as an …
Phage Cluster Relationships Identified Through Single Gene Analysis.,
2013
George Washington University
Phage Cluster Relationships Identified Through Single Gene Analysis., Kyle C Smith, Eduardo Castro-Nallar, Joshua Nb Fisher, Donald P Breakwell, Julianne H Grose, Sandra H Burnett
Computational Biology Institute
BACKGROUND: Phylogenetic comparison of bacteriophages requires whole genome approaches such as dotplot analysis, genome pairwise maps, and gene content analysis. Currently mycobacteriophages, a highly studied phage group, are categorized into related clusters based on the comparative analysis of whole genome sequences. With the recent explosion of phage isolation, a simple method for phage cluster prediction would facilitate analysis of crude or complex samples without whole genome isolation and sequencing. The hypothesis of this study was that mycobacteriophage-cluster prediction is possible using comparison of a single, ubiquitous, semi-conserved gene. Tape Measure Protein (TMP) was selected to test the hypothesis because it …
