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HIV mutant

Jie Yu, Yaoming Li, Maohua Zhong, Jingyi Yang, Dihan Zhou, Bali Zhao, Yuan Cao, Hu Yan, Ejuan Zhang, Yi Yang, Zhengshan Feng, Xiuwen Qi, Huimin Yan
The development of an effective HIV-1 vaccine is still a global priority. In recent years, vaccinia virus (VV) has been widely used as an HIV-1 vaccine vector, but its immune efficacy against HIV-1 antigens needs to be optimized. The extracellular enveloped virus (EEV) of VV is capable of faster entry, earlier release, and long-range dissemination. We hypothesized that an improvement in EEV formation by the manipulation of VV genes involved in the EEV release would consequently cause an improved expression of the VV carrying HIV-1 Env antigen and a subsequent enhanced immune response...
March 14, 2018: Antiviral Research
Eric Barklis, August O Staubus, Andrew Mack, Logan Harper, Robin Lid Barklis, Ayna Alfadhli
The matrix (MA) domain of the HIV-1 precursor Gag protein (PrGag) has been shown interact with the HIV-1 envelope (Env) protein, and to direct PrGag proteins to plasma membrane (PM) assembly sites by virtue of its affinity to phosphatidylinositol-4,5-bisphosphate (PI[4,5]P2). Unexpectedly, HIV-1 viruses with large MA deletions (ΔMA) have been shown to be conditionally infectious as long as they are matched with Env truncation mutant proteins or alternative viral glycoproteins. To characterize the interactions of wild type (WT) and ΔMA Gag proteins with PI(4,5)P2 and other acidic phospholipids, we have employed a set of lipid biosensors as probes...
March 14, 2018: Virology
Lina Rustanti, Hongping Jin, Dongsheng Li, Mary Lor, Haran Sivakumaran, David Harrich
Nullbasic is a mutant form of HIV-1 Tat that has strong ability to protect cells from HIV-1 replication by inhibiting three different steps of viral replication: reverse transcription, Rev export of viral mRNA from the nucleus to the cytoplasm and transcription of viral mRNA by RNA polymerase II. We previously showed that Nullbasic inhibits transduction of human cells including T cells by HIV-1-based lentiviral vectors. Here we investigated whether the Nullbasic antagonists huTat2 (a Tat targeting intrabody), HIV-1 Tat or Rev proteins or cellular DDX1 protein could improve transduction by a HIV-1 lentiviral vector conveying Nullbasic-ZsGreen1 to human T cells...
March 14, 2018: Virologica Sinica
Carin K Ingemarsdotter, Jingwei Zeng, Ziqi Long, Andrew M L Lever, Julia C Kenyon
BACKGROUND: NSC260594, a quinolinium derivative from the NCI diversity set II compound library, was previously identified in a target-based assay as an inhibitor of the interaction between the HIV-1 (ψ) stem-loop 3 (SL3) RNA and Gag. This compound was shown to exhibit potent antiviral activity. Here, the effects of this compound on individual stages of the viral lifecycle were examined by qRT-PCR, ELISA and Western blot, to see if its actions were specific to the viral packaging stage...
March 14, 2018: Retrovirology
Boshi Huang, Xinhao Liu, Ye Tian, Dongwei Kang, Zhongxia Zhou, Dirk Daelemans, Erik De Clercq, Christophe Pannecouque, Peng Zhan, Xinyong Liu
In the present work, we described the synthesis, antiviral profiles and metabolic stability in human plasma of compound 6, a potential carbonate prodrug of HIV-1 NNRTI drug candidate RDEA427. Compound 6 was found to inhibit the wild-type (WT) and K103N/Y181C double mutant HIV-1 strains at nano- and submicromolar concentrations, respectively. Moreover, it displayed potent HIV-1 reverse transcriptase inhibitory activity (IC50  = 0.264 μM). Further stability test in human plasma showed that 6 could release its active form RDEA427 in a linearly time-independent manner, possibly acting as a potential prodrug...
March 5, 2018: Bioorganic & Medicinal Chemistry Letters
Md Fazlur Rahman, Radhika Raj, Rajgopal Govindarajan
Combination antiretroviral drug treatments depend on 3'-deoxy-nucleoside analogs such as AZT (3'-azido-3'-deoxythymidine) and DDI (2'3'-dideoxyinosine). Despite being effective in inhibiting HIV viral replication, these drugs produce a range of toxicities, including myopathy, pancreatitis, neuropathy and lactic acidosis, that are generally considered as sequelae to mitochondrial damage. While the cell surface localized nucleoside transporters (e.g., human equilibrative nucleoside transporter 2 (hENT2), human concentrative nucleoside transporter 1 (hCNT1)) are known to increase the carrier mediated uptake of 3'-deoxy-nucleoside analogs into cells, another ubiquitously expressed intracellular nucleoside transporter, namely, hENT3, has been implicated in the mitochondrial transport of 3'-deoxy-nucleoside analogs...
March 12, 2018: Drug Metabolism and Disposition: the Biological Fate of Chemicals
Savrina Manhas, Lina Ma, Vivien Measday
Nuclear pore complexes (NPCs) orchestrate cargo between the cytoplasm and nucleus and regulate chromatin organization. NPC proteins, or nucleoporins (Nups), are required for human immunodeficiency virus type 1 (HIV-1) gene expression and genomic integration of viral DNA. We utilize the Ty1 retrotransposon of Saccharomyces cerevisiae (S. cerevisiae) to study retroviral integration because retrotransposons are the progenitors of retroviruses and have conserved integrase (IN) enzymes. Ty1-IN targets Ty1 elements into the genome upstream of RNA polymerase (Pol) III transcribed genes such as transfer RNA (tRNA) genes...
March 5, 2018: Nucleic Acids Research
Olivia Monteiro, Changwei Chen, Ryan Bingham, Argyrides Argyrou, Rachel Buxton, Christina Pancevac Jönsson, Emma Jones, Angela Bridges, Kelly Gatfield, Sybille Krauß, Jeremy Lambert, Rosamund Langston, Susann Schweiger, Iain Uings
Expression of mutant Huntingtin (HTT) protein is central to the pathophysiology of Huntington's Disease (HD). The E3 ubiquitin ligase MID1 appears to have a key role in facilitating translation of the mutant HTT mRNA suggesting that interference with the function of this complex could be an attractive therapeutic approach. Here we describe a peptide that is able to disrupt the interaction between MID1 and the α4 protein, a regulatory subunit of protein phosphatase 2A (PP2A). By fusing this peptide to a sequence from the HIV-TAT protein we demonstrate that the peptide can disrupt the interaction within cells and show that this results in a decrease in levels of ribosomal S6 phosphorylation and HTT expression in cultures of cerebellar granule neurones derived from HdhQ111/Q7 mice...
February 27, 2018: Neuroscience Letters
Vani G S Narasimhulu, Anna K Bellamy-McIntyre, Annamarie E Laumaea, Chan-Sien Lay, David N Harrison, Hannah A D King, Heidi E Drummer, Pantelis Poumbourios
HIV-1 is spread by cell-free virions and by cell-cell viral transfer. We asked whether the structure and function of a broad neutralizing antibody (bNAb) epitope, the membrane-proximal ectodomain region (MPER) of the viral gp41 transmembrane glycoprotein, differ in cell-free and cell-cell transmitted viruses and whether this difference could be related to Ab neutralization sensitivity. Whereas cell-free viruses bearing W666A and I675A substitutions in the MPER lacked infectivity, cell-associated mutant viruses were able to initiate robust spreading infection...
March 1, 2018: Journal of Biological Chemistry
Gurmit Kaur Jagjit Singh, Steve Kaye, James C Abbott, Christoph Boesecke, Juergen Rockstroh, Myra O McClure, Mark Nelson
Background The epidemic of acute HCV infection among HIV-infected men who have sex with men (MSM) is ongoing. Transmission of drug-resistant variants (DRVs) after HCV treatment failure could pose a major threat to the effectiveness of future therapies. We determined the baseline prevalence of pre-existing DRVs in the HCV NS3 protease gene and their effects on the addition of telaprevir (TVR) to standard pegylated interferon and ribavirin (PEG-IFN/RBV) for acute HCV infection in individuals enrolled in a multicentre randomized controlled trial (2013 and 2014)...
March 1, 2018: HIV Clinical Trials
P J Klasse, Thomas J Ketas, Christopher A Cottrell, Gabriel Ozorowski, Gargi Debnath, Diawoye Camara, Erik Francomano, Pavel Pugach, Rajesh P Ringe, Celia C LaBranche, Marit J van Gils, Christine A Bricault, Dan H Barouch, Shane Crotty, Guido Silvestri, Sudhir Kasturi, Bali Pulendran, Ian A Wilson, David C Montefiori, Rogier W Sanders, Andrew B Ward, John P Moore
The native-like, soluble SOSIP.664 trimer based on the BG505 clade A env gene of HIV-1 is immunogenic in various animal species, of which the most studied are rabbits and rhesus macaques. The trimer induces autologous neutralizing antibodies (NAbs) consistently but at a wide range of titers and with incompletely determined specificities. A precise delineation of immunogenic neutralization epitopes on native-like trimers could help strategies to extend the NAb response to heterologous HIV-1 strains. One autologous NAb epitope on the BG505 Env trimer is known to involve residues lining a hole in the glycan shield that is blocked by adding a glycan at either residue 241 or 289...
February 23, 2018: PLoS Pathogens
Jonathan C Reed, Nick Westergreen, Brook C Barajas, Dylan T B Ressler, Daryl J Phuong, John V Swain, Vishwanath R Lingappa, Jaisri R Lingappa
During immature capsid assembly in cells, HIV-1 Gag co-opts a host RNA granule, forming a pathway of intracellular assembly intermediates containing host components, including two cellular facilitators of assembly, ABCE1 and DDX6. A similar assembly pathway has been observed for other primate lentiviruses. Here we asked whether feline immunodeficiency virus (FIV), a non-primate lentivirus, also forms RNA-granule-derived capsid assembly intermediates. First, we showed that the released FIV immature capsid and a large FIV-Gag-containing intracellular complex are unstable during analysis, unlike for HIV-1...
February 21, 2018: Journal of Virology
Shahid N Khan, John D Persons, Janet L Paulsen, Michel Guerrero, Celia A Schiffer, Nese Kurt-Yilmaz, Rieko Ishima
In the era of state-of-the-art inhibitor design and high-resolution structural studies, detection of significant but small protein structural differences in the inhibitor-bound forms is critical to further developing the inhibitor. Here, we probed differences in HIV-1 protease (PR) conformation among darunavir and four analogous inhibitor-bound forms and compared them with a drug-resistant mutant using nuclear magnetic resonance chemical shifts. Changes in amide chemical shifts of wild-type (WT) PR among these inhibitor-bound forms, ΔCSP, were subtle but detectable and extended >10 Å from the inhibitor-binding site, asymmetrically between the two subunits of PR...
February 19, 2018: Biochemistry
Young D Kwon, Gwo-Yu Chuang, Baoshan Zhang, Robert T Bailer, Nicole A Doria-Rose, Tatyana S Gindin, Bob Lin, Mark K Louder, Krisha McKee, Sijy O'Dell, Amarendra Pegu, Stephen D Schmidt, Mangaiarkarasi Asokan, Xuejun Chen, Misook Choe, Ivelin S Georgiev, Vivian Jin, Marie Pancera, Reda Rawi, Keyun Wang, Rajoshi Chaudhuri, Lisa A Kueltzo, Slobodanka D Manceva, John-Paul Todd, Diana G Scorpio, Mikyung Kim, Ellis L Reinherz, Kshitij Wagh, Bette M Korber, Mark Connors, Lawrence Shapiro, John R Mascola, Peter D Kwong
Highly effective HIV-1-neutralizing antibodies could have utility in the prevention or treatment of HIV-1 infection. To improve the potency of 10E8, an antibody capable of near pan-HIV-1 neutralization, we engineered 10E8-surface mutants and screened for improved neutralization. Variants with the largest functional enhancements involved the addition of hydrophobic or positively charged residues, which were positioned to interact with viral membrane lipids or viral glycan-sialic acids, respectively. In both cases, the site of improvement was spatially separated from the region of antibody mediating molecular contact with the protein component of the antigen, thereby improving peripheral semi-specific interactions while maintaining unmodified dominant contacts responsible for broad recognition...
February 13, 2018: Cell Reports
Ron Zhi-Hui Chiang, Samuel Ken-En Gan, Chinh Tran-To Su
HIV drug resistant mutations that render the current Highly Active Anti-Retroviral Therapy cocktail drugs ineffective are increasingly reported. To study the mechanisms of these mutations in conferring drug resistance, we computationally analyzed fourteen Reverse Transcriptase (RT) structures of HIV-1 on the following parameters: drug-binding pocket volume, allosteric effects caused by the mutations, and structural thermal stability. We constructed structural correlation-based networks of the mutant RT-drug complexes and the analyses support the use of Efavirenz as the first-line drug, given that cross-resistance is least likely to develop from Efavirenz-resistant mutations...
February 5, 2018: Bioscience Reports
Muhamad Alif Che Nordin, Sin-Yeang Teow
The discovery of highly active antiretroviral therapy (HAART) in 1996 has significantly reduced the global mortality and morbidity caused by the acquired immunodeficiency syndrome (AIDS). However, the therapeutic strategy of HAART that targets multiple viral proteins may render off-target toxicity and more importantly results in drug-resistant escape mutants. These have been the main challenges for HAART and refinement of this therapeutic strategy is urgently needed. Antibody-mediated treatments are emerging therapeutic modalities for various diseases...
February 6, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Tomokazu Yoshinaga, Takahiro Seki, Shigeru Miki, Tadashi Miyamoto, Akemi Suyama-Kagitani, Shinobu Kawauchi-Miki, Masanori Kobayashi, Akihiko Sato, Eugene Stewart, Mark Underwood, Tamio Fujiwara
Cabotegravir (CAB, S/GSK1265744) is an investigational second-generation integrase strand transfer inhibitor (INSTI) with a chemical structure similar to dolutegravir. CAB is under development as a long-acting injectable formulation for treatment of HIV-1 infection and for pre-exposure prophylaxis. We conducted an in vitro passage study of raltegravir- or elvitegravir-resistant signature mutants in the presence of CAB to characterize the resistance profile of this drug. During passage with Q148H virus, G140S arose by day 14, followed by G149A and C56S...
January 30, 2018: Antiviral Research
Yeshambel Belyhun, Uwe Gerd Liebert, Melanie Maier
BACKGROUND: We recently reported complex hepatitis B virus (HBV) drug resistant and concomitant vaccine escape hepatitis B surface antigen (HBsAg) variants during human immunodeficiency virus (HIV) co-infection and antiretroviral therapy (ART) exposure in Ethiopia. As a continuation of this report using the HBV positive sera from the same study participants, the current study further analyzed the HBV basal core promoter (BCP)/precore (PC) genes variability in patients with HBV drug resistance (at tyrosine-methionine-aspartate-aspartate (YMDD) reverse transcriptase (RT) motifs) and HIV co-infection in comparison with HBV mono-infected counterparts with no HBV drug resistant gene variants...
2018: PloS One
Yi Chen Chen, Kun Mou Li, Raz Zarivach, Yuh Ju Sun, Shih Che Sue
The chemokine CCL5 is considered to be a potential therapeutic target because of its ability to recruit immune cells to inflammatory sites. CCL5 aggregates under physiological conditions, and high-order oligomer formation is considered to be significant for cell migration, immune-cell activation and HIV cell entry. The structure of the high-order oligomer is unknown and the mechanism by which the oligomer is derived has yet to be established. Here, a CCL5 mutant (CCL5-E66S) which is deficient in oligomer formation was mixed with native CCL5 to prepare a protein trimer...
February 1, 2018: Acta Crystallographica. Section F, Structural Biology Communications
Zainab K Sanusi, Thavendran Govender, Glenn E M Maguire, Sibusiso B Maseko, Johnson Lin, Hendrik G Kruger, Bahareh Honarparvar
The aspartate protease of the human immune deficiency type-1 virus (HIV-1) has become a crucial antiviral target in which many useful antiretroviral inhibitors have been developed. However, it seems the emergence of new HIV-1 PR mutations enhances drug resistance, hence, the available FDA approved drugs show less activity towards the protease. A mutation and insertion designated L38L↑N↑L PR was recently reported from subtype of C-SA HIV-1. An integrated two-layered ONIOM (QM:MM) method was employed in this study to examine the binding affinities of the nine HIV PR inhibitors against this mutant...
February 3, 2018: Journal of Computer-aided Molecular Design
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