Resolution of de novo HIV production and trafficking in immature dendritic cells.
AuthorsTurville SG, Aravantinou M, Stössel H, Romani N, Robbiani M,
JournalNat Methods
PubMed ID18059278
'The challenge in observing de novo virus production in human immunodeficiency virus (HIV)-infected dendritic cells (DCs) is the lack of resolution between cytosolic immature and endocytic mature HIV gag protein. To track HIV production, we developed an infectious HIV construct bearing a diothiol-resistant tetracysteine motif (dTCM) at the C terminus ... More
Androgen induces expression of the multidrug resistance protein gene MRP4 in prostate cancer cells.
AuthorsCai C, Omwancha J, Hsieh CL, Shemshedini L
JournalProstate Cancer Prostatic Dis
PubMed ID17003774
'Multidrug resistance-associated proteins (MRPs) may mediate multidrug resistance in tumor cells. Using a gene array analysis, we have identified MRP4 as an androgen receptor (AR)-regulated gene. Dihydrotestosterone induced MRP4 expression in both androgen-dependent and -independent LNCaP cells, whereas there was little detectable expression in PC-3 or normal prostate epithelial cells. ... More
H2AX phosphorylation within the G1 phase after UV irradiation depends on nucleotide excision repair and not DNA double-strand breaks.
AuthorsMarti TM, Hefner E, Feeney L, Natale V, Cleaver JE
JournalProc Natl Acad Sci U S A
PubMed ID16788066
'The variant histone H2AX is phosphorylated in response to UV irradiation of primary human fibroblasts in a complex fashion that is radically different from that commonly reported after DNA double-strand breaks. H2AX phosphorylation after exposure to ionizing radiation produces foci, which are detectable by immunofluorescence microscopy and have been adopted ... More
Rab11-family interacting proteins define spatially and temporally distinct regions within the dynamic Rab11a-dependent recycling system.
AuthorsBaetz NW, Goldenring JR,
JournalMol Biol Cell
PubMed ID23283983
'The Rab11-family interacting proteins (Rab11-FIPs) facilitate Rab11-dependent vesicle recycling. We hypothesized that Rab11-FIPs define discrete subdomains and carry out temporally distinct roles within the recycling system. We used live-cell deconvolution microscopy of HeLa cells expressing chimeric fluorescent Rab11-FIPs to examine Rab11-FIP localization, transferrin passage through Rab11-FIP-containing compartments, and overlap among ... More
High-efficiency labeling of sialylated glycoproteins on living cells.
AuthorsZeng Y, Ramya TN, Dirksen A, Dawson PE, Paulson JC,
JournalNat Methods
PubMed ID19234450
We describe a simple method for efficiently labeling cell-surface sialic acid-containing glycans on living animal cells. The method uses mild periodate oxidation to generate an aldehyde on sialic acids, followed by aniline-catalyzed oxime ligation with a suitable tag. Aniline catalysis dramatically accelerates oxime ligation, allowing use of low concentrations of ... More
Quantification of host-microbe interactions by automated fluorescence microscopy.
AuthorsHaghighat AC, Seveau S,
JournalJ Immunol Methods
PubMed ID19931271
We describe an automated fluorescence microscopy-based assay that quantifies the invasion of mammalian cells by intracellular pathogens. Pathogens associated with host cell surfaces, intracellular pathogens and mammalian cells are directly counted based on their specific fluorescent labeling. Such approach utilizes automated image acquisition and processing, and is thus ideally suited ... More
Immunohistochemical detection of tumour hypoxia.
AuthorsYoung RJ, Möller A,
JournalMethods Mol Biol
PubMed ID19960329
In this chapter, we describe the use of immunohistochemical methods to detect hypoxia in tumour tissue sections, utilising antibodies specific for endogenous proteins hypoxia inducible factor 1 alpha (Hif1alpha) and glucose transporter 1 (Glut-1) and the exogenous compound pimonidazole (Pim). Immunohistochemistry is routinely used both diagnostically and in research to ... More
Advanced laboratory techniques for sample processing and immunolabeling using microwave radiation.
AuthorsFerris AM, Giberson RT, Sanders MA, Day JR,
JournalJ Neurosci Methods
PubMed ID19520116
A better understanding of improved microwave technology has increased the benefits and versatility of the technique as it applies to all aspects of immunohistochemistry. The role of continuous magnetron power output (wattage) combined with precise control of sample heating demonstrated their significance to complex labeling protocols. Here, we present results ... More
Inhibitors of intravesicular acidification protect against Shiga toxin in a pH-independent manner.
AuthorsDyve Lingelem AB, Bergan J, Sandvig K,
JournalTraffic
PubMed ID22132807
Shiga toxin inhibits protein synthesis after being transported from the cell surface to endosomes and retrogradely through the Golgi apparatus to the endoplasmic reticulum (ER) and into the cytosol. In this study, we have abolished proton gradients across internal membranes in different ways and investigated the effect on the various ... More
Development of a functional bioassay for arylsulfatase B using the natural substrates of the enzyme.
AuthorsPungor E, Hague CM, Chen G, Lemontt JF, Dvorak-Ewell M, Prince WS,
JournalAnal Biochem
PubMed ID19682969
A functional bioassay has been developed for measuring the intracellular activity of recombinant human arylsulfatase B (rhASB) on its natural glycosaminoglycan (GAG) substrates, dermatan sulfate (DS), and chondroitin sulfate (CS) when the enzyme is taken up into cultured ASB-deficient human fibroblasts (GM00519). The enzyme ASB is a lysosomal exohydrolase, cleaving ... More
Functional scaffold-free 3-D cardiac microtissues: a novel model for the investigation of heart cells.
AuthorsDesroches BR, Zhang P, Choi BR, King ME, Maldonado AE, Li W, Rago A, Liu G, Nath N, Hartmann KM, Yang B, Koren G, Morgan JR, Mende U,
JournalAm J Physiol Heart Circ Physiol
PubMed ID22427522
To bridge the gap between two-dimensional cell culture and tissue, various three-dimensional (3-D) cell culture approaches have been developed for the investigation of cardiac myocytes (CMs) and cardiac fibroblasts (CFs). However, several limitations still exist. This study was designed to develop a cardiac 3-D culture model with a scaffold-free technology ... More
Interaction of phosphodiesterase 3A with brefeldin A-inhibited guanine nucleotide-exchange proteins BIG1 and BIG2 and effect on ARF1 activity.
AuthorsPuxeddu E, Uhart M, Li CC, Ahmad F, Pacheco-Rodriguez G, Manganiello VC, Moss J, Vaughan M,
JournalProc Natl Acad Sci U S A
PubMed ID19332778
ADP-ribosylation factors (ARFs) have crucial roles in vesicular trafficking. Brefeldin A-inhibited guanine nucleotide-exchange proteins (BIG)1 and BIG2 catalyze the activation of class I ARFs by accelerating replacement of bound GDP with GTP. Several additional and differing actions of BIG1 and BIG2 have been described. These include the presence in BIG2 ... More
Low-density Lipoprotein Receptor-related Protein-1 (LRP1) Mediates Autophagy and Apoptosis Caused by Helicobacter pylori VacA.
AuthorsYahiro K, Satoh M, Nakano M, Hisatsune J, Isomoto H, Sap J, Suzuki H, Nomura F, Noda M, Moss J, Hirayama T,
JournalJ Biol Chem
PubMed ID22822085
In Helicobacter pylori infection, vacuolating cytotoxin (VacA)-induced mitochondrial damage leading to apoptosis is believed to be a major cause of cell death. It has also been proposed that VacA-induced autophagy serves as a host mechanism to limit toxin-induced cellular damage. Apoptosis and autophagy are two dynamic and opposing processes that ... More
Dynamin-related protein 1 (Drp1)-mediated diastolic dysfunction in myocardial ischemia-reperfusion injury: therapeutic benefits of Drp1 inhibition to reduce mitochondrial fission.
AuthorsSharp WW, Fang YH, Han M, Zhang HJ, Hong Z, Banathy A, Morrow E, Ryan JJ, Archer SL,
Journal
PubMed ID24076965
Mitochondrial fission, regulated by dynamin-related protein-1 (Drp1), is a newly recognized determinant of mitochondrial function, but its contribution to left ventricular (LV) impairment following ischemia-reperfusion (IR) injury is unknown. We report that Drp1 activation during IR results in LV dysfunction and that Drp1 inhibition is beneficial. In both isolated neonatal ... More
Mitochondrial DNA (mtDNA) Biogenesis: Visualization and Duel Incorporation of BrdU and EdU Into Newly Synthesized mtDNA In Vitro.
AuthorsLentz SI, Edwards JL, Backus C, McLean LL, Haines KM, Feldman EL,
JournalJ Histochem Cytochem
PubMed ID19875847
Mitochondria are key regulators of cellular energy and are the focus of a large number of studies examining the regulation of mitochondrial dynamics and biogenesis in healthy and diseased conditions. One approach for monitoring mitochondrial biogenesis is to measure the rate of mitochondrial DNA (mtDNA) replication. We developed a sensitive ... More
A contiguous compartment functions as endoplasmic reticulum and endosome/lysosome in Giardia lamblia.
AuthorsAbodeely M, DuBois KN, Hehl A, Stefanic S, Sajid M, DeSouza W, Attias M, Engel JC, Hsieh I, Fetter RD, McKerrow JH,
JournalEukaryot Cell
PubMed ID19749174
The dynamic evolution of organelle compartmentalization in eukaryotes and how strictly compartmentalization is maintained are matters of ongoing debate. While the endoplasmic reticulum (ER) is classically envisioned as the site of protein cotranslational translocation, it has recently been proposed to have pluripotent functions. Using transfected reporter constructs, organelle-specific markers, and ... More
Homologous recombinational repair factors are recruited and loaded onto the viral DNA genome in Epstein-Barr virus replication compartments.
AuthorsKudoh A, Iwahori S, Sato Y, Nakayama S, Isomura H, Murata T, Tsurumi T,
JournalJ Virol
PubMed ID19386720
Homologous recombination is an important biological process that facilitates genome rearrangement and repair of DNA double-strand breaks (DSBs). The induction of Epstein-Barr virus (EBV) lytic replication induces ataxia telangiectasia-mutated (ATM)-dependent DNA damage checkpoint signaling, leading to the clustering of phosphorylated ATM and Mre11/Rad50/Nbs1 (MRN) complexes to sites of viral genome ... More
Killed but metabolically active microbes: a new vaccine paradigm for eliciting effector T-cell responses and protective immunity.
AuthorsBrockstedt DG, Bahjat KS, Giedlin MA, Liu W, Leong M, Luckett W, Gao Y, Schnupf P, Kapadia D, Castro G, Lim JY, Sampson-Johannes A, Herskovits AA, Stassinopoulos A, Bouwer HG, Hearst JE, Portnoy DA, Cook DN, Dubensky TW
JournalNat Med
PubMed ID16041382
We developed a new class of vaccines, based on killed but metabolically active (KBMA) bacteria, that simultaneously takes advantage of the potency of live vaccines and the safety of killed vaccines. We removed genes required for nucleotide excision repair (uvrAB), rendering microbial-based vaccines exquisitely sensitive to photochemical inactivation with psoralen ... More