N-Terminal Fragments of Tau Inhibit Full-Length Tau Polymerization in Vitro†

Peroxisome proliferator-activated receptor gamma (PPARg) is a member of the nuclear hormone receptor superfamily and has been shown in vitro to regulate genes involved in lipid metabolism and adipocyte differentiation. By Northern analysis, we and other researchers have shown that expression of this receptor predominates in adipose tissue in adult mice, and appears first in whole-embryo mRNA at 13.5 days postconception. In situ hybridization was used to find out in which developing tissues PPARg is specifically expressed.Digoxigenin-labeled riboprobes were generated using the Genius™ 4 RNA Labeling Kit from Boehringer Mannheim. Full length PPAR gamma, obtained by PCR from mouse liver cDNA, was inserted into pBluescript SK and used as template for the transcription reaction. Probes of average size 200 base pairs were made by partial alkaline hydrolysis of the full length transcripts. The in situ hybridization assays were performed as described previously with some modifications. Frozen sections (10 μm thick) of day 18 mouse embryos were cut, fixed with 4% paraformaldehyde and acetylated with 0.25% acetic anhydride in 1.0M triethanolamine buffer. The sections were incubated for 2 hours at room temperature in pre-hybridization buffer, and were then hybridized with a probe concentration of 200μg per ml at 70° C, overnight in a humidified chamber. Following stringent washes in SSC buffers, the immunological detection steps were performed at room temperature. The alkaline phosphatase labeled, anti-digoxigenin antibody and detection buffers were purchased from Boehringer Mannheim. The sections were treated with a blocking buffer for one hour and incubated with antibody solution at a 1:5000 dilution for 2 hours, both at room temperature. Colored precipitate was formed by exposure to the alkaline phosphatase substrate nitrobluetetrazoliumchloride/ bromo-chloroindlylphosphate.

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Generation of Full-Length Functional Antibody against PreS2 of Hepatitis B Virus in Hepatic Cells In Vitro from Bicistrons Mediated by Gutless Adenovirus

BioDrugs ◽

10.2165/11316940-000000000-00000 ◽

2009 ◽

Vol 23 (6) ◽

pp. 391-397

Author(s):

Yuexiang Yin ◽

Fang Lin ◽

Qiang Zhuang ◽

Li Liu ◽

Cheng Qian

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

Full Length ◽

Hepatic Cells ◽

B Virus

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Identification of Promiscuous African Swine Fever Virus T-Cell Determinants Using a Multiple Technical Approach

Vaccines ◽

10.3390/vaccines9010029 ◽

2021 ◽

Vol 9 (1) ◽

pp. 29

Author(s):

Laia Bosch-Camós ◽

Elisabet López ◽

María Jesús Navas ◽

Sonia Pina-Pedrero ◽

Francesc Accensi ◽

...

Keyword(s):

T Cell ◽

Mononuclear Cells ◽

African Swine Fever Virus ◽

African Swine Fever ◽

Cd8 T Cell ◽

Protective Role ◽

Full Length ◽

T Cell Epitopes ◽

Peripheral Blood Mononuclear

The development of subunit vaccines against African swine fever (ASF) is mainly hindered by the lack of knowledge regarding the specific ASF virus (ASFV) antigens involved in protection. As a good example, the identity of ASFV-specific CD8+ T-cell determinants remains largely unknown, despite their protective role being established a long time ago. Aiming to identify them, we implemented the IFNγ ELISpot as readout assay, using as effector cells peripheral blood mononuclear cells (PBMCs) from pigs surviving experimental challenge with Georgia2007/1. As stimuli for the ELISpot, ASFV-specific peptides or full-length proteins identified by three complementary strategies were used. In silico prediction of specific CD8+ T-cell epitopes allowed identifying a 19-mer peptide from MGF100-1L, as frequently recognized by surviving pigs. Complementarily, the repertoire of SLA I-bound peptides identified in ASFV-infected porcine alveolar macrophages (PAMs), allowed the characterization of five additional SLA I-restricted ASFV-specific epitopes. Finally, in vitro stimulation studies using fibroblasts transfected with plasmids encoding full-length ASFV proteins, led to the identification of MGF505-7R, A238L and MGF100-1L as promiscuously recognized antigens. Interestingly, each one of these proteins contain individual peptides recognized by surviving pigs. Identification of the same ASFV determinants by means of such different approaches reinforce the results presented here.

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Biological activity of transcripts synthesized in Vitro from full-length and mutated DNA copies of tobacco rattle virus RNA 2

Virology ◽

10.1016/0042-6822(89)90222-5 ◽

1989 ◽

Vol 173 (1) ◽

pp. 68-76 ◽

Cited By ~ 19

Author(s):

Gerco C. Angenent ◽

Eelke Posthumus ◽

John F. Bol

Keyword(s):

Biological Activity ◽

Tobacco Rattle Virus ◽

Full Length ◽

Virus Rna

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Prospective Characterization of Full-Length Hepatitis C Virus NS5A Quasispecies during Induction and Combination Antiviral Therapy

Journal of Virology ◽

10.1128/jvi.74.19.9028-9038.2000 ◽

2000 ◽

Vol 74 (19) ◽

pp. 9028-9038 ◽

Cited By ~ 86

Author(s):

J.-B. Nousbaum ◽

S. J. Polyak ◽

S. C. Ray ◽

D. G. Sullivan ◽

A. M. Larson ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Amino Acid ◽

Antiviral Therapy ◽

Variable Region ◽

Response To Therapy ◽

Full Length ◽

Variable Regions ◽

C Terminus

ABSTRACT The hepatitis C virus (HCV) nonstructural 5A (NS5A) protein has been controversially implicated in the inherent resistance of HCV to interferon (IFN) antiviral therapy in clinical studies. In this study, the relationship between NS5A mutations and selection pressures before and during antiviral therapy and virologic response to therapy were investigated. Full-length NS5A clones were sequenced from 20 HCV genotype 1-infected patients in a prospective, randomized clinical trial of IFN induction (daily) therapy and IFN plus ribavirin combination therapy. Pretreatment NS5A nucleotide and amino acid phylogenies did not correlate with clinical IFN responses and domains involved in NS5A functions in vitro were all well conserved before and during treatment. A consensus IFN sensitivity-determining region (ISDR237–276) sequence associated with IFN resistance was not found, although the presence of Ala245 within the ISDR was associated with nonresponse to treatment in genotype 1a-infected patients (P < 0.01). There were more mutations in the 26 amino acids downstream of the ISDR required for PKR binding in pretreatment isolates from responders versus nonresponders in both HCV-1a- and HCV-1b-infected patients (P < 0.05). In HCV-1a patients, more amino acid changes were observed in isolates from IFN-sensitive patients (P < 0.001), and the mutations appeared to be concentrated in two variable regions in the C terminus of NS5A, that corresponded to the previously described V3 region and a new variable region, 310 to 330. Selection of pretreatment minor V3 quasispecies was observed within the first 2 to 6 weeks of therapy in responders but not nonresponders, whereas the ISDR and PKR binding domains did not change in either patient response group. These data suggest that host-mediated selective pressures act primarily on the C terminus of NS5A and that NS5A can perturb or evade the IFN-induced antiviral response using sequences outside of the putative ISDR. Mechanistic studies are needed to address the role of the C terminus of NS5A in HCV replication and antiviral resistance.

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Microtubule Actin Cross-Linking Factor (Macf)

The Journal of Cell Biology ◽

10.1083/jcb.147.6.1275 ◽

1999 ◽

Vol 147 (6) ◽

pp. 1275-1286 ◽

Cited By ~ 150

Author(s):

Conrad L. Leung ◽

Dongming Sun ◽

Min Zheng ◽

David R. Knowles ◽

Ronald K.H. Liem

Keyword(s):

Calcium Binding ◽

Coiled Coil ◽

Specific Protein ◽

Binding Domain ◽

Full Length ◽

Actin Binding ◽

Cross Linking ◽

Actin Binding Domain

We cloned and characterized a full-length cDNA of mouse actin cross-linking family 7 (mACF7) by sequential rapid amplification of cDNA ends–PCR. The completed mACF7 cDNA is 17 kb and codes for a 608-kD protein. The closest relative of mACF7 is the Drosophila protein Kakapo, which shares similar architecture with mACF7. mACF7 contains a putative actin-binding domain and a plakin-like domain that are highly homologous to dystonin (BPAG1-n) at its NH2 terminus. However, unlike dystonin, mACF7 does not contain a coiled–coil rod domain; instead, the rod domain of mACF7 is made up of 23 dystrophin-like spectrin repeats. At its COOH terminus, mACF7 contains two putative EF-hand calcium-binding motifs and a segment homologous to the growth arrest–specific protein, Gas2. In this paper, we demonstrate that the NH2-terminal actin-binding domain of mACF7 is functional both in vivo and in vitro. More importantly, we found that the COOH-terminal domain of mACF7 interacts with and stabilizes microtubules. In transfected cells full-length mACF7 can associate not only with actin but also with microtubules. Hence, we suggest a modified name: MACF (microtubule actin cross-linking factor). The properties of MACF are consistent with the observation that mutations in kakapo cause disorganization of microtubules in epidermal muscle attachment cells and some sensory neurons.

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Transcriptional activation by herpes simplex virus type 1 VP16 in vitro and its inhibition by oligopeptides

Molecular and Cellular Biology ◽

10.1128/mcb.14.5.3484-3493.1994 ◽

1994 ◽

Vol 14 (5) ◽

pp. 3484-3493

Author(s):

T J Wu ◽

G Monokian ◽

D F Mark ◽

C R Wobbe

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Transcriptional Activation ◽

Deletion Mutant ◽

Full Length ◽

Early Gene ◽

Immediate Early ◽

Simplex Virus

VP16 is a herpes simplex virus (HSV)-encoded transcriptional activator protein that is essential for efficient viral replication and as such may be a target for novel therapeutic agents directed against viral gene expression. We have reconstituted transcriptional activation by VP16 in an in vitro system that is dependent on DNA sequences from HSV immediate-early gene promoters and on protein-protein interactions between VP16 and Oct-1 that are required for VP16 activation in vivo. Activation increased synergistically with the number of TAATGARAT elements (the cis-acting element for VP16 activation in vivo) upstream of the core promoter, and mutations of this element that reduce Oct-1 or VP16 DNA binding reduced transactivation in vitro. A VP16 insertion mutant unable to interact with Oct-1 was inactive, but, surprisingly, a deletion mutant lacking the activation domain was approximately 65% as active as the full-length protein. The activation domains of Oct-1 were necessary for activation in reactions containing the VP16 deletion mutant, and they contributed significantly to activation by full-length VP16. Addition of a GA-rich element present in many HSV immediate-early gene enhancers synergistically stimulated VP16-activated transcription. Finally, oligopeptides that are derived from a region of VP16 thought to contact a cellular factor known as HCF (host cell factor) and that inhibit efficient VP16 binding to the TAATGARAT element also specifically inhibited VP16-activated, but not basal, transcription. Amino acid substitutions in one of these peptides identified three residues that are absolutely required for inhibition and presumably for interaction of VP16 with HCF.

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The Mauriceville plasmid of Neurospora crassa: characterization of a novel reverse transcriptase that begins cDNA synthesis at the 3' end of template RNA

Molecular and Cellular Biology ◽

10.1128/mcb.12.11.5131-5144.1992 ◽

1992 ◽

Vol 12 (11) ◽

pp. 5131-5144

Author(s):

H Wang ◽

J C Kennell ◽

M T Kuiper ◽

J R Sabourin ◽

R Saldanha ◽

...

Keyword(s):

Reverse Transcriptase ◽

Reverse Transcription ◽

Full Length ◽

Minus Strand ◽

Ribonucleoprotein Particle ◽

Cdna Synthesis ◽

Reverse Transcriptases ◽

In Vitro Transcripts

The Mauriceville and Varkud plasmids are retroid elements that propagate in the mitochondria of some Neurospora spp. strains. Previous studies of endogenous reactions in ribonucleoprotein particle preparations suggested that the plasmids use a novel mechanism of reverse transcription that involves synthesis of a full-length minus-strand DNA beginning at the 3' end of the plasmid transcript, which has a 3' tRNA-like structure (M. T. R. Kuiper and A. M. Lambowitz, Cell 55:693-704, 1988). In this study, we developed procedures for releasing the Mauriceville plasmid reverse transcriptase from mitochondrial ribonucleoprotein particles and partially purifying it by heparin-Sepharose chromatography. By using these soluble preparations, we show directly that the Mauriceville plasmid reverse transcriptase synthesizes full-length cDNA copies of in vitro transcripts beginning at the 3' end and has a preference for transcripts having the 3' tRNA-like structure. Further, unlike retroviral reverse transcriptases, the Mauriceville plasmid reverse transcriptase begins cDNA synthesis directly opposite the 3'-terminal nucleotide of the template RNA. The ability to initiate cDNA synthesis directly at the 3' end of template RNAs may also be relevant to the mechanisms of reverse transcription used by LINEs, group II introns, and other non-long terminal repeat retroid elements.

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Progastrin1–80stimulates growth of intestinal epithelial cells in vitro via high-affinity binding sites

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00351.2002 ◽

2003 ◽

Vol 284 (2) ◽

pp. G328-G339 ◽

Cited By ~ 41

Author(s):

P. Singh ◽

X. Lu ◽

S. Cobb ◽

B. T. Miller ◽

N. Tarasova ◽

...

Keyword(s):

Epithelial Cells ◽

Binding Sites ◽

Intestinal Epithelial Cells ◽

Full Length ◽

Intestinal Epithelial ◽

Growth Effects ◽

High Affinity ◽

Significant Difference

Proliferation and carcinogenesis of the large intestinal epithelial cells (IEC) cells is significantly increased in transgenic mice that overexpress the precursor progastrin (PG) peptide. It is not known if the in vivo growth effects of PG on IEC cells are mediated directly or indirectly. Full-length recombinant human PG (rhPG1–80) was generated to examine possible direct effects of PG on IEC cells. Surprisingly, rhPG (0.1–1.0 nM) was more effective than the completely processed gastrin 17 (G17) peptide as a growth factor. Even though IEC cells did not express CCK1and CCK2receptors (-R), fluorescently labeled G17 and Gly-extended G17 (G-Gly) were specifically bound to the cells, suggesting the presence of binding proteins other than CCK1-R and CCK2-R on IEC cells. High-affinity ( Kd= 0.5–1.0 nM) binding sites for125I-rhPG were discovered on IEC cells that demonstrated relative binding affinity for gastrin-like peptides in the order PG ≥ COOH-terminally extended G17 ≥ G-Gly > G17 > *CCK-8 (* significant difference; P< 0.05). In conclusion, our studies demonstrate for the first time direct growth effects of the full-length precursor peptide on IEC cells in vitro that are apparently mediated by the high-affinity PG binding sites that were discovered on these cells.

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