scholarly journals Interaction of Clostridium perfringens Iota Toxin and Lipolysis-Stimulated Lipoprotein Receptor (LSR)

Toxins ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 405 ◽  
Author(s):  
Masahiro Nagahama ◽  
Masaya Takehara ◽  
Keiko Kobayashi
Keyword(s):  
Lipid Rafts ◽  
Clostridium Perfringens ◽  
Green Fluorescence Protein ◽  
Lipoprotein Receptor ◽  
Green Fluorescence ◽  
Extracellular Region ◽  
Cytoplasmic Vesicles ◽  
Clostridium Perfringens Iota Toxin ◽  
Fluorescence Protein ◽  
Binding Component

Iota toxin produced by Clostridium perfringens is a binary, actin ADP-ribosylating toxin that is organized into the enzymatically active component Ia and the binding component Ib. Lipolysis-stimulated lipoprotein receptor (LSR) has been identified as a cellular receptor of Ib. Here, we investigated the functional interaction between Ib and LSR, where siRNA for LSR blocked the toxin-mediated cytotoxicity and the binding of Ib. The addition of Ib to LSR-green fluorescence protein (GFP)-transfected cells at 4 °C resulted in colocalization with LSR and Ib on the cell surface. Upon transfer of the cells from 4 °C to 37 °C, LSR and Ib were internalized and observed in cytoplasmic vesicles. When the cells were incubated with Ib at 37 °C and fractionated using the Triton-insoluble membrane, Ib oligomer was localized in insoluble factions that fulfilled the criteria of lipid rafts, and LSR was clustered in lipid rafts. To examine the interaction between N-terminal extracellular region of LSR and Ib, we constructed a series of LSR N-terminal deletions. Ten amino acids residues can be deleted from this end without any reduction of Ib binding. However, deletion of 15 N-terminal residues drastically reduces its ability to bind Ib. These results demonstrate that Ib binds to the LSR N-terminal 10 to 15 residues and endocytoses into trafficking endosomes together with LSR.

scholarly journals Binding and Internalization of Clostridium perfringens Iota-Toxin in Lipid Rafts

2004 ◽  
Vol 72 (6) ◽  
pp. 3267-3275 ◽  
Author(s):  
Masahiro Nagahama ◽  
Akiwo Yamaguchi ◽  
Tohko Hagiyama ◽  
Noriko Ohkubo ◽  
Keiko Kobayashi ◽  
...  
Keyword(s):  
Lipid Rafts ◽  
Clostridium Perfringens ◽  
Mdck Cells ◽  
Binary Toxin ◽  
Surface Plasmon Resonance Analysis ◽  
Resonance Analysis ◽  
Cytoplasmic Vesicles ◽  
Raft Fraction ◽  
Clostridium Perfringens Iota Toxin ◽  
Binding Component

ABSTRACT Clostridium perfringens iota-toxin is a binary toxin composed of an enzymatic component (Ia) and a binding component (Ib). The oligomer of Ib formed in membranes induces endocytosis. We examined the binding and internalization of Ib by using Cy3-labeled Ib. Labeled Ib was retained at the membranes of MDCK cells for 60 min of incubation at 37°C, and later it was detected in cytoplasmic vesicles. To determine whether Ib associates with lipid rafts, we incubated MDCK cells with Ib at 4 or 37°C and fractionated the Triton-insoluble membranes. An Ib complex of 500 kDa was localized at 37°C to the insoluble fractions that fulfilled the criteria of lipid rafts, but it did not form at 4°C. The amount of complex in the raft fraction reached a maximum after 60 min of incubation at 37°C. When the cells that were preincubated with Ib at 4°C were incubated at 37°C, the complex was detected in the raft fraction. The treatment of MDCK cells with methyl-β-cyclodextrin reduced the localization of the Ib complex to the rafts and the rounding of the cells induced by Ia plus Ib. When 125I-labeled Ia was incubated with the cells in the presence of Ib at 37°C, it was localized in the raft fraction. Surface plasmon resonance analysis revealed that Ia binds to the oligomer of Ib. We conclude that Ib binds to a receptor in membranes and then moves to rafts and that Ia bound to the oligomer of Ib formed in the rafts is internalized.

An enhanced green fluorescence protein (EGFP)-based reporter assay for quantitative detection of sporulation in Clostridium perfringens SM101

2019 ◽  
Vol 291 ◽  
pp. 144-150 ◽  
Author(s):  
Yuki Wakabayashi ◽  
Hirofumi Nariya ◽  
Mayo Yasugi ◽  
Tomomi Kuwahara ◽  
Mahfuzur R. Sarker ◽  
...  
Keyword(s):  
Clostridium Perfringens ◽  
Green Fluorescence Protein ◽  
Quantitative Detection ◽  
Reporter Assay ◽  
Green Fluorescence ◽  
Enhanced Green Fluorescence Protein ◽  
Fluorescence Protein

scholarly journals Expansion of EasyClone-MarkerFree toolkit for Saccharomyces cerevisiae genome with new integration sites

2021 ◽  
Author(s):  
Mahsa Babaei ◽  
Luisa Sartori ◽  
Alexey Karpukhin ◽  
Dmitrii Abashkin ◽  
Elena Matrosova ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Recombinant Dna ◽  
Green Fluorescence Protein ◽  
Cellular Growth ◽  
Green Fluorescence ◽  
Biotechnological Production ◽  
Yeast Saccharomyces Cerevisiae ◽  
Integration Sites ◽  
Fluorescence Protein ◽  
Integration Efficiency

Abstract Biotechnological production requires genetically stable recombinant strains. To ensure genomic stability, recombinant DNA is commonly integrated into the genome of the host strain. Multiple genetic tools have been developed for genomic integration into baker's yeast Saccharomyces cerevisiae. Previously, we had developed a vector toolkit EasyClone-MarkerFree for stable integration into eleven sites on chromosomes X, XI, and XII of S. cerevisiae. The markerless integration was enabled by CRISPR-Cas9 system. In this study, we have expanded the kit with eight additional intergenic integration sites located on different chromosomes. The integration efficiency into the new sites was above 80%. The expression level of green fluorescence protein (gfp) for all eight sites was similar or above XI-2 site from the original EasyClone-MarkerFree toolkit. The cellular growth was not affected by the integration into any of the new eight locations. The eight-vector expansion kit is available from AddGene.

Establishment of an Embryotoxicity Assay with Green Fluorescence Protein-expressing Embryonic Cell-derived Cardiomyocytes

1999 ◽  
Vol 27 (3) ◽  
pp. 471-484 ◽  
Author(s):  
Susanne Bremer ◽  
Maaike Van Dooren ◽  
Martin Paparella ◽  
Eugen Kossolov ◽  
Bernd Fleischmann ◽  
...  
Keyword(s):  
Green Fluorescence Protein ◽  
Embryonic Cell ◽  
Green Fluorescence ◽  
Fluorescence Protein

scholarly journals Fertility of mice receiving vitrified adult mouse ovaries

Reproduction ◽  
2006 ◽  
Vol 131 (4) ◽  
pp. 681-687 ◽  
Author(s):  
Toshio Hani ◽  
Takanori Tachibe ◽  
Saburo Shingai ◽  
Nobuo Kamada ◽  
Otoya Ueda ◽  
...  
Keyword(s):  
Germ Cells ◽  
Adult Mouse ◽  
Green Fluorescence Protein ◽  
Green Fluorescence ◽  
Experimental Animals ◽  
Immature Mouse ◽  
Estrous Cyclicity ◽  
Fluorescence Protein ◽  
High Degree ◽  
Old Mice

Cryopreservation of the ovaries is a useful technology for preservation of germ cells from experimental animals, because if the female founder is infertile or has mutated mitochondrial DNA, preservation of female germ cells is necessary. Although it is possible to cryopreserve immature mouse ovaries with a high degree of viability by vitrification with a mixture of several cryoprotectants, the viability of cryopreserved adult mouse ovaries is still unknown. Here, we investigated the viability of mouse ovaries at various ages after cryopreservation by vitrification techniques. Donor ovaries were collected from 10-day-, 4-week-, 10-week- and 7-month-old, female, nulliparous, green fluorescence protein (GFP)-transgenic mice and cryopreserved by vitrification. The vitrified-warmed ovaries were orthotopically transplanted to 4- or 10-week-old mice. GFP-positive pups were obtained in all experimental groups. In the 4-week-old recipients, the percentages of GFP-positive pups among the total pups from recipients transplanted with ovaries of 10-day-, 4-week-, 10-week- and 7-month-old donors were 44%, 9%, 12% and 4% respectively. In the 10-week-old recipients, the percentages of GFP-positive pups among the total pups from recipients transplanted with ovaries of 10-day-, 4-week-, 10-week- and 7-month-old donors were 36%, 16%, 2% and 9% respectively. Furthermore, GFP-positive pups also were obtained from recipients transplanted with ovaries of donors without normal estrous cyclicity. Our results indicate that cryopreservation of mouse ovaries by vitrification is a useful method for the preservation of female germ cells from mice of various ages.

scholarly journals Binding Component of Clostridium perfringens Iota-Toxin Induces Endocytosis in Vero Cells

2002 ◽  
Vol 70 (4) ◽  
pp. 1909-1914 ◽  
Author(s):  
Masahiro Nagahama ◽  
Koichi Nagayasu ◽  
Keiko Kobayashi ◽  
Jun Sakurai
Keyword(s):  
Clostridium Perfringens ◽  
Vero Cells ◽  
Binary Toxin ◽  
Wild Type ◽  
Oligomer Formation ◽  
Clostridium Perfringens Iota Toxin ◽  
Binding Component ◽  
Pronase Treatment

ABSTRACT Clostridium perfringens iota-toxin is a binary toxin consisting of two individual proteins, the binding component (Ib) and the enzyme component (Ia). Wild-type Ib bound to Vero cells at 4 and 37°C and formed oligomers at 37°C but not at 4°C. The Ib-induced K+ release from the cells was dependent on the oligomer formation of Ib in the cells, but the oligomer formation did not induce rounding activity or cytotoxicity. After incubation of the cells with recombinant Ib (rIb) at 37°C, the Ib oligomer in the cell became resistant to pronase treatment with time, but the Ib monomer was sensitive to the treatment. Furthermore, treatment of Vero cells with rIb in the presence of bafilomycin, methylamine, or ethylamine resulted in accumulation of the oligomer in the cells but had no effect on K+ release. Moreover, incubation with Ib plus Ia in the presence of these agents caused no rounding in the cells. These observations suggest that Ib binds to Vero cells, itself oligomerizing to form ion-permeable channels and that the formation of oligomer then induces endocytosis.

scholarly journals Construction and Characterization of a Recombinant Human Respiratory Syncytial Virus Encoding Enhanced Green Fluorescence Protein for Antiviral Drug Screening Assay

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Min Xu ◽  
Yue-Ying Jiao ◽  
Yuan-Hui Fu ◽  
Nan Jiang ◽  
Yuan-Bo Zheng ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Respiratory Tract ◽  
Drug Screening ◽  
Green Fluorescence Protein ◽  
Respiratory Tract Disease ◽  
Green Fluorescence ◽  
Enhanced Green Fluorescence Protein ◽  
Fluorescence Protein ◽  
Syncytial Virus ◽  
Tract Disease

Human respiratory syncytial virus (RSV) is the single most important cause of lower respiratory tract disease in infants and young children and a major viral agent responsible for respiratory tract disease in immunosuppressed individuals and the elderly, but no vaccines and antiviral drugs are available. Herein the recombinant RSV (rRSV) encoding enhanced green fluorescence protein (EGFP, rRSV-EGFP) was constructed and the potential for screening anti-RSV drugs was investigated. The recombinant plasmid of pBRATm-rRSV-EGFP, containing T7 transcription cassette composed of T7 promoter, RSV antigenomic cDNA with EGFP gene, HDV ribozyme (δ), and T7 terminator in the order of 5′ to 3′, was constructed and cotransfected into BHK/T7-9 cells together with helper plasmids encoding N, P, L, and M2-1 gene, respectively. The rescued rRSV-EGFP was confirmed by increasing expression of EGFP over blind passages and by RT-PCR. rRSV-EGFP was comparable to the other two recombinant RSVs encoding red fluorescent protein (RFP, rRSV-RFP) or luciferase (Luc, rRSV-Luc) in the growth kinetic, and there was a difference in sensitivity between them for screening anti-RSV agents based on infection of HEp-2 cells. The EGFP-encoding rRSV has been constructed and rescued successfully and has the potential for high-throughput anti-RSV drug screening in vitro.

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