Evaluating vanadium bioavailability to cabbage in rural soils using geochemical and micro-spectroscopic techniques.

Assessing the vanadium (V) fractionation and speciation to predict its bioavailability using a combined approach of geochemical extractions and micro-spectroscopic techniques is still not well studied. Therefore, we aimed to determine the bioavailability of V in rural soils using single extractants, sequential extraction procedure, and the X-ray absorption near edge structure (XANES) spectroscopy. We collected and characterized ninety four samples originated from horizons of seventeen soil profiles in Taiwan.

Epigenetic regulation affects gene amplification in Drosophila development.

In Drosophila melanogaster, in response to developmental transcription factors, and by repeated initiation of DNA replication of four chorion genes, ovarian follicle cells, form an onion skin-type structure at the replication origins. The DNA replication machinery is conserved from yeast to humans. Subunits of the origin recognition complex (ORC) is comprised of Orc1, Orc2, and Cdc6 genes.

Comparison of Sample Preparation Methods for Multielements Analysis of Olive Oil by ICP-MS.

Elemental analysis of olive oils by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is challenging because of the high organic load in olive oil samples and the low analyte concentrations. However, conflicting operating procedures in the preparation of oils prior to analysis by ICP-MS have been reported to overcome these difficulties. This study compared three methods of inorganic elements' extraction from olive oils: The two commonly used microwave-assisted, acid digestion, and liquid-liquid, ultrasound-assisted extraction methods; and an optimized method: The combined microwave digestion-evaporation.

Interregional traceability of Tunisian olive oils to the provenance soil by multielemental fingerprinting and chemometrics.

The aim of this study was to prove the usefulness of multielements as provenance markers of olive oils by evaluating their link with soil composition and their discriminatory power. Eleven elements in twenty-one olive oils and their paired soils from four Tunisian regions were characterized. Chemometrics have been implemented for ICP-MS data processing.

Seabird-affected taluses are denitrification hotspots and potential NO emitters in the High Arctic.

In High Arctic tundra ecosystems, seabird colonies create nitrogen cycling hotspots because of bird-derived labile organic matter. However, knowledge about the nitrogen cycle in such ornithocoprophilous tundra is limited. Here, we determined denitrification potentials and in-situ nitrous oxide (NO) emissions of surface soils on plant-covered taluses under piscivorous seabird cliffs at two sites (BL and ST) near Ny-Ålesund, Svalbard, in the European High Arctic.

Endoreduplication of the mouse genome in the absence of ORC1.

The largest subunit of the origin recognition complex (ORC1) is essential for assembly of the prereplicative complex, firing of DNA replication origins, and faithful duplication of the genome. Here, we generated knock-in mice with sites flanking exons encoding the critical ATPase domain of ORC1. Global or tissue-specific ablation of ORC1 function in mouse embryo fibroblasts and fetal and adult diploid tissues blocked DNA replication, cell lineage expansion, and organ development.

DNA replication machinery is required for development in .

In , some factors involved in chromosome replication seem to be involved in gene amplification and endoreplication, which are actively utilized in particular tissue development, but direct evidence has not been shown. Therefore, we examined the effect of depletion of replication factors on these processes. First, we confirmed RNAi knockdown can be used for the depletion of replication factors by comparing the phenotypes of RNAi knockdown and deletion or point mutants of the components of DNA licensing factor, MCM2, MCM4 and Cdt1.

Chromosome and genetic testing using ChIP assay.

Chromatin immunoprecipitation (ChIP) assay can be used to easily visualize information about proteins, DNA, and RNA on chromosomes and is widely used for analysis of genomes, epigenomes, mRNAs, and non-coding RNAs. The ChIP assay can detect, not only DNA-binding proteins of various organisms, but also the temporal and spatial regulating mechanisms of RNA-binding proteins. Because of these features, demand for ChIP assay is expected to grow.

Internal structure of cesium-bearing radioactive microparticles released from Fukushima nuclear power plant.

Microparticles containing substantial amounts of radiocesium collected from the ground in Fukushima were investigated mainly by transmission electron microscopy (TEM) and X-ray microanalysis with scanning TEM (STEM). Particles of around 2 μm in diameter are basically silicate glass containing Fe and Zn as transition metals, Cs, Rb and K as alkali ions, and Sn as substantial elements. These elements are homogeneously distributed in the glass except Cs which has a concentration gradient, increasing from center to surface.

[A case and literature review of ovarian carcinosarcoma with long-term survival after repeated recurrences].

Ovarian carcinosarcoma is a rare and aggressive tumor with a poor prognosis. We report a case of ovarian carcinosarcoma and also review the literature. In 2000, a 63-year-old woman underwent optimal cytoreductive surgery for ovarian carcinosarcoma( International Federation of Gynaecology and Obstetrics[FIGO]stage III c[pT3cN0M0]).

Arsenic biotransformation by Streptomyces sp. isolated from rice rhizosphere.

Isolation and functional analysis of microbes mediating the methylation of arsenic (As) in paddy soils is important for understanding the origin of dimethylarsinic acid (DMA) in rice grains. Here, we isolated from the rice rhizosphere a unique bacterium responsible for As methylation. Strain GSRB54, which was isolated from the roots of rice plants grown in As-contaminated paddy soil under anaerobic conditions, was classified into the genus Streptomyces by 16S ribosomal RNA sequencing.

An orc1 allele with a mutated APC motif is female sterile with amplification defects.

The origin recognition complex 1 (ORC1) is the largest subunit of the ORC, the heteromeric hexamer. ORC1 is an essential component of the pre-replicative complex (pre-RC) that licenses eukaryote DNA replication origins. The levels of ORC1 fluctuate during the mitotic cell cycle in Drosophila as well as in some human cells.

Function of the origin recognition complex 1 (ORC1) outside DNA replication in Drosophila.

The origin recognition complex (ORC) is an essential component of the pre-replicative complex (pre-RC) that binds to replication origins for licensing. Levels of the largest ORC subunit, ORC1, oscillate during the mitotic cell cycle and regulate origin usage. In Drosophila, ORC1 levels increase at the G(1)/S transition following E2F-dependent transcriptional activation, remain high until the end of M phase and then decrease at the M/G(1) transition when ORC1 is targeted for proteolysis by the anaphase-promoting complex (APC).

Endoreplication: the advantage to initiating DNA replication without the ORC?

The endocycle is a developmentally specialized cell cycle that lacks M phase and consists of only S and G phases. Endoreplicating cells acquire high ploidies by multiple rounds of replication without cell divisions in order to increase protein synthesis to support growth and development of the organism. Endoreplication occurs in developmentally specialized cell types after they terminally differentiate.

The origin recognition complex is dispensable for endoreplication in Drosophila.

The origin recognition complex (ORC) is an essential component of the prereplication complex (pre-RC) in mitotic cell cycles. The role of ORC as a foundation to assemble the pre-RC is conserved from yeast to human. Furthermore, in metazoans ORC plays a key role in determining the timing of replication initiation and origin usage.

APC/CFzr/Cdh1 promotes cell cycle progression during the Drosophila endocycle.

The endocycle is a commonly observed variant cell cycle in which cells undergo repeated rounds of DNA replication with no intervening mitosis. How the cell cycle machinery is modified to transform a mitotic cycle into endocycle has long been a matter of interest. In both plants and animals, the transition from the mitotic cycle to the endocycle requires Fzr/Cdh1, a positive regulator of the Anaphase-Promoting Complex/Cyclosome (APC/C).

A role for Cdc2- and PP2A-mediated regulation of Emi2 in the maintenance of CSF arrest.

Background: Vertebrate oocytes are arrested in metaphase II of meiosis prior to fertilization by cytostatic factor (CSF). CSF enforces a cell-cycle arrest by inhibiting the anaphase-promoting complex (APC), an E3 ubiquitin ligase that targets Cyclin B for degradation. Although Cyclin B synthesis is ongoing during CSF arrest, constant Cyclin B levels are maintained.

Transcriptional regulation of the Drosophila orc2 gene by the DREF pathway.

DNA replication-related element (DRE) and the DRE-binding factor (DREF) play an important role in regulating DNA replication-related genes such as PCNA and DNA polymerase alpha in Drosophila. We have previously reported that overexpression of DREF in developing eye imaginal discs induced ectopic DNA synthesis and apoptosis, which results in rough eyes. To identify genetic interactants with the DREF gene, we have carried out a screen for modifiers of the rough eye phenotype.

A novel motif governs APC-dependent degradation of Drosophila ORC1 in vivo.

Regulated degradation plays a key role in setting the level of many factors that govern cell cycle progression. In Drosophila, the largest subunit of the origin recognition complex protein 1 (ORC1) is degraded at the end of M phase and throughout much of G1 by anaphase-promoting complexes (APC) activated by Fzr/Cdh1. We show here that none of the previously identified APC motifs targets ORC1 for degradation.

Degradation of origin recognition complex large subunit by the anaphase-promoting complex in Drosophila.

The initiation of DNA synthesis is thought to occur at sites bound by a heteromeric origin recognition complex (ORC). Previously, we have shown that in Drosophila, the level of the large subunit, ORC1, is modulated during cell cycle progression and that changes in ORC1 concentration alter origin utilization during development. Here, we investigate the mechanisms underlying cell cycle-dependent degradation of ORC1.