91 research outputs found
Heparan sulfate proteoglycan is an important attachment factor for cell entry of Akabane and Schmallenberg viruses
Akabane (AKAV) and Schmallenberg (SBV) viruses are Orthobunyavirus transmitted by arthropod vectors with a broad cellular tropism in vitro as well as in vivo Both AKAV and SBV cause arthrogryposis-hydranencephaly syndrome in ruminants. The main cellular receptor and attachment factor for entry of these orthobunyaviruses are unknown. Here, we found that AKAV and SBV infections were inhibited by the addition of heparin or enzymatic removal of cell surface heparan sulfates. To confirm this finding, we prepared heparan sulfate proteoglycan (HSPG)-knockout (KO) cells by using a CRISPR/Cas9 system and measured the binding quantities of these viruses to cell surfaces. We observed a substantial reduction in AKAV and SBV binding to cells, limiting the infections by these viruses. These data demonstrate that HSPGs are important cellular attachment factors for AKAV and SBV, at least in vitro, to promote virus replication in susceptive cells.
Importance: AKAV and SBV are the etiological agents of arthrogryposis-hydranencephaly syndrome in ruminants, which causes considerable economic losses in the livestock industry. Here, we identified heparan sulfate proteoglycan as a major cellular attachment factor for the entry of AKAV and SBV. Moreover, we found that heparin is a strong inhibitor of AKAV and SBV infections. Revealing the molecular mechanisms of virus-host interactions is critical in order to understand virus biology and develop novel live attenuated vaccines
Enhanced growth of seed viruses for H5N1 influenza vaccines
AbstractSeed viruses used to produce inactivated H5N1 influenza vaccines are recombinant viruses with modified avirulent-type hemagglutinin (HA) and intact neuraminidase (NA) genes, both derived from an H5N1 isolate, and all remaining genes from the PR8 strain, which grows well in eggs. However, some reassortants grow suboptimally in eggs, imposing obstacles to timely, cost-efficient vaccine production. Here, we demonstrate that our PR8 strain supports better in ovo growth than the PR8 strain used for the WHO-recommended seed virus, NIBRG-14. Moreover, inclusion of an alternative NA protein further enhanced viral growth in eggs. These findings suggest that our H5N1 vaccine candidates would increase the availability of H5N1 vaccine doses at the onset of a new pandemic
Senescence-inducing stress promotes proteolysis of phosphoglycerate mutase via ubiquitin ligase Mdm2.
細胞老化から癌化への変換のカギとなる解糖系制御機構解明に成功 -代謝を標的とした新しい抗がん剤開発に期待-. 京都大学プレスリリース. 2014-02-24.Despite the well-documented clinical significance of the Warburg effect, it remains unclear how the aggressive glycolytic rates of tumor cells might contribute to other hallmarks of cancer, such as bypass of senescence. Here, we report that, during oncogene- or DNA damage-induced senescence, Pak1-mediated phosphorylation of phosphoglycerate mutase (PGAM) predisposes the glycolytic enzyme to ubiquitin-mediated degradation. We identify Mdm2 as a direct binding partner and ubiquitin ligase for PGAM in cultured cells and in vitro. Mutations in PGAM and Mdm2 that abrogate ubiquitination of PGAM restored the proliferative potential of primary cells under stress conditions and promoted neoplastic transformation. We propose that Mdm2, a downstream effector of p53, attenuates the Warburg effect via ubiquitination and degradation of PGAM
White Paper from Workshop on Large-scale Parallel Numerical Computing Technology (LSPANC 2020): HPC and Computer Arithmetic toward Minimal-Precision Computing
In numerical computations, precision of floating-point computations is a key
factor to determine the performance (speed and energy-efficiency) as well as
the reliability (accuracy and reproducibility). However, precision generally
plays a contrary role for both. Therefore, the ultimate concept for maximizing
both at the same time is the minimal-precision computing through
precision-tuning, which adjusts the optimal precision for each operation and
data. Several studies have been already conducted for it so far (e.g.
Precimoniuos and Verrou), but the scope of those studies is limited to the
precision-tuning alone. Hence, we aim to propose a broader concept of the
minimal-precision computing system with precision-tuning, involving both
hardware and software stack.
In 2019, we have started the Minimal-Precision Computing project to propose a
more broad concept of the minimal-precision computing system with
precision-tuning, involving both hardware and software stack. Specifically, our
system combines (1) a precision-tuning method based on Discrete Stochastic
Arithmetic (DSA), (2) arbitrary-precision arithmetic libraries, (3) fast and
accurate numerical libraries, and (4) Field-Programmable Gate Array (FPGA) with
High-Level Synthesis (HLS).
In this white paper, we aim to provide an overview of various technologies
related to minimal- and mixed-precision, to outline the future direction of the
project, as well as to discuss current challenges together with our project
members and guest speakers at the LSPANC 2020 workshop;
https://www.r-ccs.riken.jp/labs/lpnctrt/lspanc2020jan/
Combination chemotherapy for small cell carcinoma of the lung: evaluation of four-drug combination of cyclophosphamide, vincristine, methotrexate, and procarbazine.
Forty-one patients with small cell carcinoma of the lung were treated with a four-drug combination of cyclophosphamide, vincristine, methotrexate, and procarbazine. The response rate was 68% (28 responded among 41 patients), with 10 complete responses (24%) and 18 partial responses (44%). The median survival time from the initiation of chemotherapy was 11 months for patients with limited disease and 8 months for those with extensive disease. Patients who achieved complete response survived significantly longer than those who did not; the median survival time for complete responders was 14.5 months, compared to 8.5 months for partial responders and 6 months for non-responders. Myelosuppressive toxicity remained within acceptable limits, with 5% incidence of leukocytopenia (less than 1,000/microliter) and 7% incidence of thrombocytopenia (less than 50,000/microliter) following the first course of the regimen.</p
DOCK2 is involved in the host genetics and biology of severe COVID-19
「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target
The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force
「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection
Bovine viral diarrhea virus non?structural protein NS4B inducesautophagosomes in bovine kidney cells
AbstractBovine viral diarrhea virus (BVDV) is an important pathogen in cattle that causes economic losses in livestock industries.Autophagy is an essential cell system for the maintenance of homeostasis and is induced by various triggers, including infectionby viruses. BVDV infection leads to autophagy in order to enhance its replication in cells. In this study, we investigatedthe effect of BVDV non-structural proteins on the induction of autophagosomes. We found that NS4B alone could induceautophagosomes, suggesting a novel and important function of NS4B in BVDV replication
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