Enterovirus type 71 2A protease functions as a transcriptional activator in yeast

Enterovirus type 71 (EV71) 2A protease exhibited strong transcriptional activity in yeast cells. The transcriptional activity of 2A protease was independent of its protease activity. EV71 2A protease retained its transcriptional activity after truncation of 40 amino acids at the N-terminus but lost this activity after truncation of 60 amino acids at the N-terminus or deletion of 20 amino acids at the C-terminus. Thus, the acidic domain at the C-terminus of this protein is essential for its transcriptional activity. Indeed, deletion of amino acids from 146 to 149 (EAME) in this acidic domain lost the transcriptional activity of EV71 2A protein though still retained its protease activity. EV71 2A protease was detected both in the cytoplasm and nucleus using confocal microscopy analysis. Coxsackie virus B3 2A protease also exhibited transcriptional activity in yeast cells. As expected, an acidic domain in the C-terminus of Coxsackie virus B3 2A protease was also identified. Truncation of this acidic domain resulted in the loss of transcriptional activity. Interestingly, this acidic region of poliovirus 2A protease is critical for viral RNA replication. The transcriptional activity of the EV71 or Coxsackie virus B3 2A protease should play a role in viral replication and/or pathogenesis

A theoretical and empirical study on unbiased boundary-extended crossover for real-valued representation

Copyright © 2012 Elsevier. NOTICE: this is the author’s version of a work that was accepted for publication in Information Sciences. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Information Sciences Vol. 183 Issue 1 (2012), DOI: 10.1016/j.ins.2011.07.013We present a new crossover operator for real-coded genetic algorithms employing a novel methodology to remove the inherent bias of pre-existing crossover operators. This is done by transforming the topology of the hyper-rectangular real space by gluing opposite boundaries and designing a boundary extension method for making the fitness function smooth at the glued boundary. We show the advantages of the proposed crossover by comparing its performance with those of existing ones on test functions that are commonly used in the literature, and a nonlinear regression on a real-world dataset

Hepatitis C virus non-structural protein 3 interacts with cytosolic 5'(3')-deoxyribonucleotidase and partially inhibits its activity.

Infection with hepatitis C virus (HCV) is etiologically involved in liver cirrhosis, hepatocellular carcinoma and B-cell lymphomas. It has been demonstrated previously that HCV non-structural protein 3 (NS3) is involved in cell transformation. In this study, a yeast two-hybrid screening experiment was conducted to identify cellular proteins interacting with HCV NS3 protein. Cytosolic 5'(3')-deoxyribonucleotidase (cdN, dNT-1) was found to interact with HCV NS3 protein. Binding domains of HCV NS3 and cellular cdN proteins were also determined using the yeast two-hybrid system. Interactions between HCV NS3 and cdN proteins were further demonstrated by co-immunoprecipitation and confocal analysis in cultured cells. The cellular cdN activity was partially repressed by NS3 protein in both the transiently-transfected and the stably-transfected systems. Furthermore, HCV partially repressed the cdN activity while had no effect on its protein expression in the systems of HCV sub-genomic replicons and infectious HCV virions. Deoxyribonucleotidases are present in most mammalian cells and involve in the regulation of intracellular deoxyribonucleotides pools by substrate cycles. Control of DNA precursor concentration is essential for the maintenance of genetic stability. Reduction of cdN activity would result in the imbalance of DNA precursor concentrations. Thus, our results suggested that HCV partially reduced the cdN activity via its NS3 protein and this may in turn cause diseases

Association of Common Variants in OLA1 Gene with Preclinical Atherosclerosis

Reactive oxygen species impair the blood vessels, leading to the initiation of atherosclerosis, and migration and proliferation of vascular smooth muscle cells and neovascularization by endothelial cells of vasa vasorum are essential for atherosclerosis development. Obg-like ATPase 1 (OLA1), a negative regulator in cellular responses to oxidative stress, binds to breast cancer susceptibility gene 1 (BRCA1), which protects vascular endothelial and smooth muscle cells against reactive oxygen species. However, it is not known whether OLA1 is genetically correlated with atherosclerosis. Here, we conducted two independent population-based case–control studies to explore the effects of variants in OLA1 genes on preclinical atherosclerosis. A total of 564 and 746 subjects who had thicker and normal carotid intima–media thickness (cIMT), respectively, were enrolled. Among 55 screened SNPs, rs35145102, rs201641962, rs12466587, rs4131583, and rs16862482 in OLA1 showed significant associations with cIMT. SNP rs35145102 is a 3′-utr variant and correlates with the differential expression of OLA1 in immune cells. These five genetic markers form a single closely linked block and H1-ATTGT and H2-GCCTC were the top two most prevalent 5-locus haplotypes. The H1 + H1 genotype negatively and H1 + H2 genotype positively correlated with thicker cIMT. The five identified SNPs in the OLA1 gene showed significant correlations with cIMT. Furthermore, we found that OLA1 was required for migration and proliferation of human aortic endothelial and smooth muscle cells and regulated vascular tube formation by human aortic endothelial cells. Therefore, these genetic variants in the OLA1 gene may serve as markers for risk prediction of atherosclerotic diseases

Majority of 5′(3′)-deoxyribonucleotidase activity in the HuH7 cells is from the cdN protein.

<p>(A, B) The amount of de-phosphorylation of dUMP correlated with the amount of cdN protein. (A) (Left) HuH7 cells were transfected with empty vector (lane 1) or the cdN plasmid (lane 2). At 48 hrs after transfection, proteins derived from these cells were analyzed using antibodies against V5 tag to detect the exogenous cdN expression (upper panel) or against Erk-2 as a loading control (bottom panel). (Right) The 5′(3′)-deoxyribonucleotidase activity was determined by measuring the relative amount of de-phosphorylation of dUMP. (B) (Left) HuH 7 cells were transduced with lentiviral vector expressing shLuc or a shRNA targeting cdN. After puromycin selection, proteins derived from these cells were analyzed by Western blotting using antibodies against cdN protein to determine the knockdown efficiency (upper panel) or against Erk-2 as a loading control (bottom panel). (Right) The results of 5′(3′)-deoxyribonucleotidase activity assay. (C) The mdN protein was not the major contributor for 5′(3′)-deoxyribonucleotidase activity by measuring the relative level of the de-phosphorylation of dUMP in HuH7 cells. (Left) HuH 7 cells were transduced with lentiviral vector expressing shLuc or the shRNA targeting mdN. After puromycin selection, proteins derived from these cells were analyzed by Western blotting using antibodies against mdN protein to determine the knockdown efficiency (upper panel) or against Erk-2 as a loading control (bottom panel). (Right) The results of 5′(3′)-deoxyribonucleotidase activity assay.</p

HCV NS3 protein partially represses cellular cdN activity.

<p>(A) HuH7 cells were mock-transfected (lane 1) or transfected with empty vector (3 ug, lane 2), the cdN plasmid (3 ug, lane 3) or different amount of myc-NS3/4A plasmids (1 ug, lane 4; 1.5 ug, lane 5; 2 ug, lane 6; 3 ug, lane 7) together with empty vectors to a total of 3 ug DNA in each experiment. At 48 hrs after transfection, proteins derived from these cells were analyzed using antibodies against myc tag to detect the expression of exogenous NS3/4A protein (upper panel), against V5 tag to detect the exogenous cdN expression (middle panel) or against Erk-2 as a loading control (bottom panel). (B) The 5′(3′)-deoxyribonucleotidase activity was measured using cell lysates derived from (A). (C) HuH7 cells were mock-transduced (lane 1) or transduced with lentiviral vectors expressing EGFP (lane 2) or HCV NS3/4A protein (lane 3). After puromycin selection, proteins derived from these cells were analyzed using antibodies against NS3 (upper panel), against EGFP, against cdN protein or against Erk-2 as a loading control (bottom panel). (D) The 5′(3′)-deoxyribonucleotidase activity was analyzed using cell lysates derived from (C).</p

Cellular cdN protein did not affect HCV replication.

<p>(A) HCV replicon cells were transfected with empty vector (lane 2) or the plasmid expressing cdN protein with a V5 tag (lane 3). At 48 hrs after transfection, proteins derived from these cells were analyzed by Western blotting using antibodies against NS5A to reflect HCV replication (upper left panel), against V5 to detect cdN expression (right panel) or against actin as a loading control (bottom left panel). Proteins derived from mock-transfected HuH7 cells (lane 1) were served as a negative control for the detection of NS5A. (B) HCV replicon cells were transduced with lentiviral vectors expressing shLuc (lane 1) or different shRNAs targeting cdN gene (lanes 2-6). After puromycin selection, proteins derived from these cells were analyzed by Western blotting using antibodies against NS5A to reflect HCV replication (upper panel), against cdN protein to determine the knockdown efficiency (middle panel) or against Erk-2 as a loading control (bottom panel).</p

Interactions between HCV NS3 and cellular cdN proteins in yeast.

<p>Growth of yeasts that had been either mock-transfected or transfected with different combinations of plasmids as indicated; the transfected yeast cells were grown in YEPD without tryptophan and leucine (A and C), or YEPD without tryptophan, leucine and histidine (B and D). (E) Summarized results of (A) and (B): HCV NS3 protease domain interacts with cdN (a.a. 66-109). (F) Summarized results of (C) and (D).</p