细菌sRNA数据库

细菌sRNA是一类长度在50～500 nt的调控小RNA（small regulatory RNA）,主要通过与靶标mRNA或靶标蛋白质结合发挥多种生物学功能。目前,随着生物信息学与高通量测序的应用,发现了越来越多的细菌sRNA,开发了多个相关数据库。为了sRNA工作者系统了解与应用这些数据,本文拟对包含细菌sRNA的综合数据库和细菌sRNA专业数据库作一概述,并对sRNA数据库的未来发展进行展望。     

A cell clone strain from <Emphasis Type="Italic">Mythimna separata</Emphasis> (Lepidoptera: Noctuidae) highly susceptible to <Emphasis Type="Italic">Autographa californica</Emphasis> multiple nucleopolyhedrovirus (AcMNPV) and <Emphasis Type="Italic">M. separata</Emphasis> NPV (MsNPV)

In this study, we describe a cell line, Ms-10C, cloned from the line QAU-Ms-E-10 (simplified Ms-10), an embryonic line from Mythimna separata. The cloned cell line was significantly more sensitive to nucleopolyhedrovirus (NPV). Ms-10C cells were mainly spherical with a diameter of 14.42 ± 2.23 μm. DNA amplification fingerprinting (DAF) confirmed the profile of PCR-amplified bands of the cloned cell line was consistent with those of the parental cell line, Ms-10. The sequencing result of the mitochondrial cytochrome c oxidase I (mtCO I) fragment confirmed that the amplified 636-bps mtCOI fragment was 100% identical to that of M. separata. Its chromosomes exhibited the typical characters of lepidopteran cell lines. Its population doubling time was 42.2 h at 27°C. Ms-10C was more sensitive than Ms-10 to both Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and M. separata nucleopolyhedrovirus (MsNPV). At 4 d post infection, the infection rates of two viruses reached 94.2 and 92.3%, respectively. The availability of this cell clone strain will provide a useful tool for the basic research on nucleopolyhedrovirus and for potential application in expression of recombinant proteins with baculovirus expression vector system.     

Fluctuation of ROS regulates proliferation and mediates inhibition of migration by reducing the interaction between DLC1 and CAV-1 in breast cancer cells

The aim of our present study was to elucidate the effects of up-regulation and down-regulation of intracellular reactive oxygen species (ROS) level on proliferation, migration, and related molecular mechanism. Breast cancer cells were treated by catalase or H₂O₂. MTT, colony formation assay, and Hoechst/PI staining were used to evaluate proliferation and apoptosis. The level of intracellular ROS was measured by dichlorodihydrofluorescein diacetate probes. The ability of migration was detected by wound healing. Western blotting and coimmunoprecipitation (co-IP) were used to determine the expression of DLC1 and CAV-1 and their interaction. Our data indicated that up-regulation of intracellular ROS induced by H₂O₂ significantly inhibited proliferation and induced apoptosis accompanying G1 cell cycle arrest and elevated expression of p53. For cell migration, either up-regulation or down-regulation of ROS induced migration inhibition with reduction of interaction between DLC1 and CAV-1. Our results suggested that up-regulation of intracellular ROS inhibited proliferation by promoting expression of p53 and induced G1 cycle arrest and apoptosis. Fluctuation of ROS inhibited migration through reducing the interaction between DLC1 and CAV-1.     

Computational resources and tools for antimicrobial peptides

Antimicrobial peptides (AMPs), as evolutionarily conserved components of innate immune system, protect against pathogens including bacteria, fungi, viruses, and parasites. In general, AMPs are relatively small peptides (<10 kDa) with cationic nature and amphipathic structure and have modes of action different from traditional antibiotics. Up to now, there are more than 19 000 AMPs that have been reported, including those isolated from nature sources or by synthesis. They have been considered to be promising substitutes of conventional antibiotics in the quest to address the increasing occurrence of antibiotic resistance. However, most AMPs have modest direct antimicrobial activity, and their mechanisms of action, as well as their structure–activity relationships, are still poorly understood. Computational strategies are invaluable assets to provide insight into the activity of AMPs and thus exploit their potential as a new generation of antimicrobials. This article reviews the advances of AMP databases and computational tools for the prediction and design of new active AMPs. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.     

Health risk assessment of Chinese consumers to lead via diet

This paper investigated the concentrations of Pb in foods and the potential health risk from Pb exposure via surveys and a literature review. It was shown that the mean Pb concentration in different food groups was in the following decreasing order: marine products > meat > egg > vegetable > cereal > bean> dairy > fruit. More precisely, on average the weekly Pb intake (mg kg^?1 bw week^?1) for men, women, 2–3-year-old children, and 4–17-year-old children was 0.0055, 0.0059, 0.0145, and 0.0091, respectively. We used both deterministic and probabilistic methods to estimate the target hazard quotients (THQs) by comparing the dietary Pb intake estimation with respect to the provisional tolerable weekly intake (PTWI). The result showed that THQ values were lower than 1 in most cases, except the 97.5th percentile THQ values for 2–3-year-old children, and the probability of greater dietary Pb exposure than the tolerant weekly intake (THQ > 1) were 0.2%, 0.6%, 3.7%, and 1.2% for adult men, women, 2–3-year-old children, and 4–17-year-old children, respectively, indicating a low health risk for Chinese consumers. Among all groups, children, especially 2–3-year-old children were the most sensitive sub-population with regard to Pb exposure. Finally, it still appeared necessary to continue undertaking efforts to reduce exposure to Pb.     

(−)‐Epicatechin rescues the As2O3‐induced HERG K+ channel deficiency possibly through upregulating transcription factor SP1 expression

(?)‐Epicatechin (EPI) has beneficial effects on the cardiovascular disease. The human ether‐a‐go‐go‐related gene (HERG) potassium channel is crucial for repolarization of cardiac action potential. Dysfunction of the HERG channel can cause long QT syndrome type 2 (LQT2). Arsenic trioxide (As₂O₃) has shown efficacy in the treatment of acute promyelocytic leukemia. However, As₂O₃ can induce the deficiency of HERG channel and cause LQT2. In this study, we examined whether EPI could rescue the As₂O₃‐induced HERG channel deficiency. We found that 3 μM EPI obviously increased protein expression and current of HERG channel. EPI was able to recover the protein expression and current of HERG channel disrupted by As₂O₃. EPI was able to increase the expression of SP1 protein and recover the expression of SP1 protein disrupted by As₂O₃. In addition, EPI significantly shortened action potential duration prolonged by As₂O₃. Our data suggest that EPI rescues As₂O₃‐induced HERG channel deficiency through upregulating SP1 expression.     

Geraniin suppresses ovarian cancer growth through inhibition of NF‐κB activation and downregulation of Mcl‐1 expression

This study investigated the anticancer effects of geraniin on ovarian cancer cells and the signaling pathways involved. Ovarian cancer cells were treated with different concentrations of geraniin for 48 h and examined for viability, apoptosis, mitochondrial membrane depolarization, and gene expression. Xenograft tumor studies were performed to determine the anticancer activity of geraniin in vivo. Geraniin significantly decreased cancer cell viability in a concentration‐dependent fashion. Geraniin significantly triggered apoptosis, which was accompanied by loss of mitochondrial membrane potential and increased cytochrome c release and caspsase‐3 activity. Mechanistically, geraniin significantly downregulated Mcl‐1 and impaired NF‐κB p65 binding to the mcl‐1 promoter. Overexpression of Mcl‐1 significantly reversed geraniin‐induced apoptosis in OVCAR3 cells. In addition, geraniin retarded ovarian cancer growth and reduced expression of phospho‐p65 and Mcl‐1. Collectively, geraniin elicits growth suppression in ovarian cancer through inhibition of NF‐κB and Mcl‐1 and may provide therapeutic benefits for this malignancy.     

Synthesis and structure of a new trinuclear nickel(II) complex bridged by N‐[3‐(Dimethylamino)propyl]‐N′‐(2‐hydroxyphenyl)oxamido: in vitro anticancer activities,and reactivities toward DNA and protein

A new trinickel(II) complex bridged by N‐[3‐(dimethylamino)propyl]‐ N ′‐(2‐hydroxylphenyl)oxamido (H₃pdmapo), namely [Ni₃(pdmapo)₂(H₂O)₂]?4CH₃OH, was synthesized and characterized by X‐ray single‐crystal diffraction and other methods. In the molecule, two symmetric cis‐ pdmapo^3? mononickel(II) complexes as a “complex ligand” using the carbonyl oxygen atoms coordinate to the center nickel(II) ion situated on an inversion point. The Ni···Ni distance through the oxamido bridge is 5.2624(4) Å. The center nickel(II) ion and the lateral ones have octahedral and square‐planar coordination geometries, respectively. In the crystal, a three‐dimensional supramolecular network dominated by hydrogen bonds is observed. The reactivity toward DNA/protein bovine serum albumin (BSA) revealed that the complex could interact with herring sperm DNA (HS‐DNA) through the intercalation mode and quench the intrinsic fluorescence of BSA via a static mechanism. The in vitro anticancer activities suggested that the complex is active against the selected tumor cell lines.