Editor\u27s Notes, Chiba Medical Journal 90-1

Multiple sequence alignment of deduced amino acid sequences of 25 wheat annexin genes with rice annexin OsAnn2 (Os05g31760) obtained by ClustalW. (PDF 212 kb

Tetrahedral DNA Nanostructure-Engineered Paper-Based Electrochemical Aptasensor for Fumonisin B1 Detection Coupled with Au@Pt Nanocrystals as an Amplification Label

Fumonisin B1 (FB1), as one of the highest toxicity mycotoxins, poses a serious threat to animal and human health, even at low concentrations. It is significant and challenging to develop a sensitive and reliable analytical device. Herein, a paper-based electrochemical aptasensor was designed utilizing tetrahedral DNA nanostructures (TDNs) to controllably anchor an aptamer (Apt), improving the recognition efficiency of Apt to its target. First, gold nanoparticles (AuNPs)@MXenes were used as a sensing substrate with good conductivity and modified on the electrode for immobilization of complementary DNA–TDNs (cDNA–TDNs). In the absence of FB1, numerous Apt–Au@Pt nanocrystals (NCs) was hybridized with cDNA and assembled on the sensing interface, which accelerated the oxidation of TMB with H2O2 and produced a highly amplified differential pulse voltammetry (DPV) signal. When the target FB1 specifically bound to its Apt, the electrochemical signal was decreased by releasing the Apt–Au@Pt NCs from double-stranded DNA (dsDNA). On account of the strand displacement reaction by FB1 triggering, the aptasensor had a wider dynamic linear range (from 50 fg/mL to 100 ng/mL) with a lower limit of detection (21 fg/mL) under the optimized conditions. More impressively, the designed FB1 aptasensor exhibited satisfactory performance in corn and wheat samples. Therefore, the TDN-engineered sensing platform opens an effective approach for sensitive and accurate analysis of FB1, holding strong potential in food safety and public health

Compound 1 inhibited cellular activation of GTPases.

<p>Rab7 (A), Cdc42 (B), and Ras (C) in response to growth factor stimulation. HeLa cells were treated with sequential starvation, compound addition and EGF stimulation. Active GTPases in the cell lysates were quantified using effector linked glutathione beads, probed with fluorescent antibody and analyzed on flow cytometer. Results are given as (sample MCF—negative control MCF)/positive control MCF where the negative control is the MCF reading obtained using lysates from unstimulated cells, and the positive control is the MCF reading obtained from the stimulated cells treated with DMSO.</p

A Pan-GTPase Inhibitor as a Molecular Probe

<div><p>Overactive GTPases have often been linked to human diseases. The available inhibitors are limited and have not progressed far in clinical trials. We report here a first-in-class small molecule pan-GTPase inhibitor discovered from a high throughput screening campaign. The compound CID1067700 inhibits multiple GTPases in biochemical, cellular protein and protein interaction, as well as cellular functional assays. In the biochemical and protein interaction assays, representative GTPases from Rho, Ras, and Rab, the three most generic subfamilies of the GTPases, were probed, while in the functional assays, physiological processes regulated by each of the three subfamilies of the GTPases were examined. The chemical functionalities essential for the activity of the compound were identified through structural derivatization. The compound is validated as a useful molecular probe upon which GTPase-targeting inhibitors with drug potentials might be developed.</p></div

Additional file 13: of Comprehensive analyses of the annexin gene family in wheat

Full set of annexin sequences from wheat (T. aestivum), barely (H.vulgare), T.urartu and A.tauschii. (PDF 208 kb

Additional file 2: Table S2. of Comprehensive analyses of the annexin gene family in wheat

Description of T.aestivum, T.urartu, A.tauschii and H.vulgare annexin genes. (PDF 46 kb

Lack of covalent bond formation between GTPases and compound 1.

<p>Rab7 (A), Cdc42 (B) or Ras (C) was incubated with or without compound <b>1</b> overnight followed by extensive washing. Binding of BODIPY^-FL GTP to GTPases was indistinguishable whether the enzymes had been treated with compound <b>1</b> or not.</p

Compound 1 inhibited EGFR degradation in SCC-12F cells.

<p>A. Immunoblots of EGFR at different time points after treatment with <b>1</b> at different concentrations or DMSO. Actin served as a loading control. Each experiment included duplicate samples and was repeated in triplicate. B. Time course of EGFR degradation. The ratio of EGFR to actin was quantified at different time points and compared to time zero when ligand EGF was added.</p

Compound 1 inhibited cellular activation of GTPases.

<p>Rab7 (A), Cdc42 (B), and Ras (C) in response to growth factor stimulation. HeLa cells were treated with sequential starvation, compound addition and EGF stimulation. Active GTPases in the cell lysates were quantified using effector linked glutathione beads, probed with fluorescent antibody and analyzed on flow cytometer. Results are given as (sample MCF—negative control MCF)/positive control MCF where the negative control is the MCF reading obtained using lysates from unstimulated cells, and the positive control is the MCF reading obtained from the stimulated cells treated with DMSO.</p

Compound 1 structure and dose-response curves.

<p>(A) Structure of <b>1</b> and sites of functionalization. Shaded areas are modified regions for SAR. (B) General structure of compound <b>1</b> and analogues. (C) The concentration dependence of compound <b>1</b> on BODIPY^- FL GTP binding to eight GTPases. (D) The concentration dependence of compound <b>1</b> on BODIPY^-FL GDP binding to eight GTPases. Data shown in (C) are representative of at least three independent sets of measurements with each set conducted in duplicate. All the data points from each set were used to fit the sigmoidal dose-response equation. Percent response was calculated as the ratio of (sample MCF–negative control MCF) / (positive control MCF–negative control MCF). For the positive control, DMSO instead of the compound was added; for the negative control, the compound was replaced with GTP at a concentration 5000 fold greater than BODIPY^-FL GTP. MCF stands for median channel fluorescence.</p