bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production of IgM Specific Recombinant Dengue Multiepitope Protein for Early Diagnosis of Dengue Infection
Authors: Tripathi Nagesh K. , Shrivastva Ambuj , Pattnaik Priyabrata , Parida Manmohan , Dash Paban K. , Gupta Nimesh , Jana Asha M. , Rao P. V. Lakshmana 
Published: January 2007

AbstractDengue virus infections have recently undergone dramatic expansion in range, affecting several tropical and subtropical regions of the world. Early detection of dengue infection based on the identification of antibodies has emerged as a practical and reliable means of diagnosis of dengue fever. The recombinant dengue multiepitope (rDME‐M) protein specific to IgM in E. coli was produced in a 5‐L fermentor for use in diagnostic purpose. After fermentation, dry cell weight was approximately 11.8 g/L of the culture. The rDME‐M protein was purified under denaturing conditions using single‐step nickel nitrilotriacetate (Ni‐NTA) affinity chromatography. The final yield of purified rDME‐M protein from this method was approximately 68.5 mg/L of the culture. The purity of rDME‐M protein was checked by SDS‐PAGE analysis, and the reactivity of this protein was further checked by Western blotting and enzyme‐linked immunosorbent assay (ELISA). The purified protein was used as an antigen in the development of an in‐house dipstick ELISA and evaluated with a panel of 80 patient sera, characterized using commercially available tests for detection of dengue antibody. The results were in excellent agreement with those of IgM capture ELISA (Pan‐Bio) and rapid immunochromatography (IC) test (Pan‐Bio). These results show that the in‐house dipstick ELISA using rDME‐M protein can be used as a promising kit because of its comparable sensitivity, specificity, field applicability, and low cost.
Cholesteric mesophases
Authors: P Sixou  , J M Gilli  , A Ten Bosch  , F Fried  , P Maïssa  , L Varichon  , M H Godinho  
Published: January 2007

In the past few years, there have been important developments concerning the role and the use of chirality in liquid crystals. An example which is now relatively well known is the chiral smecticC* low molecular weight liquid crystal (LMWLC) which lowers the response time of displays by a factor between one hundred and one thousand [1-3]. In chiral liquid crystal polymers (cholesteric or twisted nematic and smecticC*), it is necessary to understand the relation between the chemical structure and the properties of mesophases in liquid and solid polymer. Furthermore, chirality is also found in abundance in biopolymers and may be important for life processes. Applications in industry (high modulus fibers, sensors, non linear optics...) have already been realised or are being pursued.The aim of this paper is to emphasize the polymer character of these liquid crystals. What is the influence of the molecular weight, the degree of substitution, the viscoelasticity and the existence of a glass transition? How to use the polymer character to obtain new informations on the liquid crystal state or to make new devices?This rapid overview roughly covers the following parts:(1) Formation and general properties of cholesteric mesophases: we give a rapid discussion of thermotropics and lyotropics, of the influence of degree of polymerisation, degree of substitution, concentration, temperature..., on the cholesteric-isotropic transition and on the order observed by textures or as described more quantitatively by the order parameter.(2) Optical properties: we give a brief presentation of a theoretical work concerning the pitch prediction taking into account the asymmetric term in the interaction potential and the comparison with experimental results.(3) Textures and defects which are mainly observed in these mesophases.(4) Flow properties and rheological behaviour which are fundamental for processing.(5) Blue phases near the isotropic-cholesteric transition which are discussed with emphasis on the specificity of the polymer state.It is usual to distinguish main chain and side chain liquid crystal polymers [4, 5], which may be modelled as indicated in Fig. 1.Cellulosic derivatives are good examples of main chain cholesteric polymers [6]. Cellulose is a very abundant polymer: each year, biosynthesis produces about 1011tons of cellulose. It readily accepts grafting of substituents, thus producing derivatives like cellulose acetate of hydroxypropylcellulose.Examples of side chain liquid crystal polymers are those obtained with homo- or copolymers of polyacrilate, polymethacrylate or polysiloxane.
Electrospray ionisation-cleavable tandem nucleic acid mass tag–peptide nucleic acid conjugates: synthesis and applications to quantitative genomic analysis using electrospray ionisation-MS/MS
Authors: Thompson Andrew , Prescott Mark , Chelebi Noorhan , Smith John , Brown Tom , Schmidt Günter 
Published: January 2007

Abstract
The synthesis and characterization of isotopomer tandem nucleic acid mass tag–peptide nucleic acid (TNT–PNA) conjugates is described along with their use as electrospray ionisation-cleavable (ESI-Cleavable) hybridization probes for the detection and quantification of target DNA sequences by electrospray ionisation tandem mass spectrometry (ESI-MS/MS). ESI-cleavable peptide TNT isotopomers were introduced into PNA oligonucleotide sequences in a total synthesis approach. These conjugates were evaluated as hybridization probes for the detection and quantification of immobilized synthetic target DNAs using ESI-MS/MS. In these experiments, the PNA portion of the conjugate acts as a hybridization probe, whereas the peptide TNT is released in a collision-based process during the ionization of the probe conjugate in the electrospray ion source. The cleaved TNT acts as a uniquely resolvable marker to identify and quantify a unique target DNA sequence. The method should be applicable to a wide variety of assays requiring highly multiplexed, quantitative DNA/RNA analysis, including gene expression monitoring, genetic profiling and the detection of pathogens.
OsCSLD1, a Cellulose Synthase-Like D1 Gene, Is Required for Root Hair Morphogenesis in Rice
Authors: Kim Chul Min , Park Sung Han , Je Byoung Il , Park Su Hyun , Park Soon Ju , Piao Hai Long , Eun Moo Young , Dolan Liam , Han Chang-deok 
Published: January 2007

AbstractRoot hairs are long tubular outgrowths that form on the surface of specialized epidermal cells. They are required for nutrient and water uptake and interact with the soil microflora. Here we show that the Oryza sativa cellulose synthase-like D1 (OsCSLD1) gene is required for root hair development, as rice (Oryza sativa) mutants that lack OsCSLD1 function develop abnormal root hairs. In these mutants, while hair development is initiated normally, the hairs elongate less than the wild-type hairs and they have kinks and swellings along their length. Because the csld1 mutants develop the same density and number of root hairs along their seminal root as the wild-type plants, we propose that OsCSLD1 function is required for hair elongation but not initiation. Both gene trap expression pattern and in situ hybridization analyses indicate that OsCSLD1 is expressed in only root hair cells. Furthermore, OsCSLD1 is the only member of the four rice CSLD genes that shows root-specific expression. Given that the Arabidopsis (Arabidopsis thaliana) gene KOJAK/AtCSLD3 is required for root hair elongation and is expressed in the root hair, it appears that OsCSLD1 may be the functional ortholog of KOJAK/AtCSLD3 and that these two genes represent the root hair-specific members of this family of proteins. Thus, at least part of the mechanism of root hair morphogenesis in Arabidopsis is conserved in rice.
An Arabidopsis Homolog of YeastATG6/VPS30Is Essential for Pollen Germination
Authors: Fujiki Yuki , Yoshimoto Kohki , Ohsumi Yoshinori 
Published: January 2007

AbstractYeast (Saccharomyces cerevisiae) Atg6/Vps30 is required for autophagy and the sorting of vacuolar hydrolases, such as carboxypeptidase Y. In higher eukaryotes, however, roles for ATG6/VPS30 homologs in vesicle sorting have remained obscure. Here, we show that AtATG6, an Arabidopsis (Arabidopsis thaliana) homolog of yeast ATG6/VPS30, restored both autophagy and vacuolar sorting of carboxypeptidase Y in a yeast atg6/vps30 mutant. In Arabidopsis cells, green fluorescent protein-AtAtg6 protein localized to punctate structures and colocalized with AtAtg8, a marker protein of the preautophagosomal structure. Disruption of AtATG6 by T-DNA insertion resulted in male sterility that was confirmed by reciprocal crossing experiments. Microscopic analyses of AtATG6 heterozygous plants (AtATG6/atatg6) crossed with the quartet mutant revealed that AtATG6-deficient pollen developed normally, but did not germinate. Because other atatg mutants are fertile, AtAtg6 likely mediates pollen germination in a manner independent of autophagy. We propose that Arabidopsis Atg6/Vps30 functions not only in autophagy, but also plays a pivotal role in pollen germination.
empty pericarp4Encodes a Mitochondrion-Targeted Pentatricopeptide Repeat Protein Necessary for Seed Development and Plant Growth in Maize
Authors: Gutiérrez-Marcos José F. , Dal Prà Mauro , Giulini Anna , Costa Liliana M. , Gavazzi Giuseppe , Cordelier Sylvain , Sellam Olivier , Tatout Christophe , Paul Wyatt , Perez Pascual , Dickinson Hugh G. , Consonni Gabriella 
Published: January 2007

AbstractThe pentatricopeptide repeat (PPR) family represents one of the largest gene families in plants, with &gt;440 members annotated in Arabidopsis thaliana. PPR proteins are thought to have a major role in the regulation of posttranscriptional processes in organelles. Recent studies have shown that Arabidopsis PPR proteins play an essential, nonredundant role during embryogenesis. Here, we demonstrate that mutations in empty pericarp4 (emp4), a maize (Zea mays) PPR-encoding gene, confer a seed-lethal phenotype. Mutant endosperms are severely impaired, with highly irregular differentiation of transfer cells in the nutrient-importing basal endosperm. Analysis of homozygous mutant plants generated from embryo-rescue experiments indicated that emp4 also affects general plant growth. The emp4-1 mutation was identified in an active Mutator (Mu) population, and cosegregation analysis revealed that it arose from a Mu3 element insertion. Evidence of emp4 molecular cloning was provided by the isolation of four additional emp4 alleles obtained by a reverse genetics approach. emp4 encodes a novel type of PPR protein of 614 amino acids. EMP4 contains nine 35–amino acid PPR motifs and an N-terminal mitochondrion-targeted sequence peptide, which was confirmed by a translational EMP4–green fluorescent protein fusion that localized to mitochondria. Molecular analyses further suggest that EMP4 is necessary to regulate the correct expression of a small subset of mitochondrial transcripts in the endosperm.
Arabidopsis PLDζ2Regulates Vesicle Trafficking and Is Required for Auxin Response
Authors: Li Gang , Xue Hong-Wei 
Published: January 2007

AbstractPhospholipase D (PLD) and its product, phosphatidic acid (PA), play key roles in cellular processes, including stress and hormonal responses, vesicle trafficking, and cytoskeletal rearrangements. We isolated and functionally characterized Arabidopsis thaliana PLDζ2, which is expressed in various tissues and enhanced by auxin. A PLDζ2-defective mutant, pldζ2, and transgenic plants deficient in PLDζ2 were less sensitive to auxin, had reduced root gravitropism, and suppressed auxin-dependent hypocotyl elongation at 29°C, whereas transgenic seedlings overexpressing PLDζ2 showed opposite phenotypes, suggesting that PLDζ2 positively mediates auxin responses. Studies on the expression of auxin-responsive genes and observation of the β-glucuronidase (GUS) expression in crosses between pldζ2 and lines containing DR5-GUS indicated that PLDζ2, or PA, stimulated auxin responses. Observations of the membrane-selective dye FM4-64 showed suppressed vesicle trafficking under PLDζ2 deficiency or by treatment with 1-butanol, a PLD-specific inhibitor. By contrast, vesicle trafficking was enhanced by PA or PLDζ2 overexpression. Analyses of crosses between pldζ2 and lines containing PIN-FORMED2 (PIN2)–enhanced green fluorescent protein showed that PLDζ2 deficiency had no effect on the localization of PIN2 but blocked the inhibition of brefeldin A on PIN2 cycling. These results suggest that PLDζ2 and PA are required for the normal cycling of PIN2-containing vesicles as well as for function in auxin transport and distribution, and hence auxin responses.
Arabidopsis KAM2/GRV2 Is Required for Proper Endosome Formation and Functions in Vacuolar Sorting and Determination of the Embryo Growth Axis
Authors: Tamura Kentaro , Takahashi Hideyuki , Kunieda Tadashi , Fuji Kentaro , Shimada Tomoo , Hara-Nishimura Ikuko 
Published: January 2007

Abstract
We isolated an Arabidopsis thaliana mutant, katamari2 (kam2), that has a defect in the organization of endomembranes. This mutant had deformed endosomes and formed abnormally large aggregates with various organelles. Map-based cloning revealed that kam2 is allelic to gravitropism defective 2 (grv2). The KAM2/GRV2 gene encodes a homolog of a DnaJ domain–containing RECEPTOR-MEDIATED ENDOCYTOSIS-8, which is considered to play a vital role in the endocytotic pathway from the plasma membrane to lysosomes in animal cells. Immunofluorescent staining showed that KAM2/GRV2 protein localizes on punctate structures, which did not merge with any markers for Golgi, trans-Golgi network, endosomes, or prevacuolar compartments. KAM2/GRV2, which does not have a predicted transmembrane domain, was peripherally associated with the membrane surface of uncharacterized compartments. KAM2/GRV2 was expressed at the early to middle stages of seed maturation. We found kam2 mis-sorted seed storage proteins by secreting them from cells, indicating that KAM2/GRV2 is involved in the transport of the proteins into protein storage vacuoles. kam2 had another defect in embryogenesis. Half of the developing kam2-1 cotyledons grew into the opposite space of the seeds before the walking stick–shaped embryo stage. Our findings suggest that KAM2/GRV2 is required for proper formation of the endosomes involving protein trafficking to the vacuoles and determination of growth axis of the embryo.
ARF7 and ARF19 Regulate Lateral Root Formation via Direct Activation ofLBD/ASLGenes inArabidopsis
Authors: Okushima Yoko , Fukaki Hidehiro , Onoda Makoto , Theologis Athanasios , Tasaka Masao 
Published: January 2007

AbstractLateral root formation in Arabidopsis thaliana is regulated by two related AUXIN RESPONSE FACTORs, ARF7 and ARF19, which are transcriptional activators of early auxin response genes. The arf7 arf19 double knockout mutant is severely impaired in lateral root formation. Target-gene analysis in arf7 arf19 transgenic plants harboring inducible forms of ARF7 and ARF19 revealed that ARF7 and ARF19 directly regulate the auxin-mediated transcription of LATERAL ORGAN BOUNDARIES-DOMAIN16/ASYMMETRIC LEAVES2-LIKE18 (LBD16/ASL18) and/or LBD29/ASL16 in roots. Overexpression of LBD16/ASL18 and LBD29/ASL16 induces lateral root formation in the absence of ARF7 and ARF19. These LBD/ASL proteins are localized in the nucleus, and dominant repression of LBD16/ASL18 activity inhibits lateral root formation and auxin-mediated gene expression, strongly suggesting that these LBD/ASLs function downstream of ARF7- and ARF19-dependent auxin signaling in lateral root formation. Our results reveal that ARFs regulate lateral root formation via direct activation of LBD/ASLs in Arabidopsis.
The Acyltransferase GPAT5 Is Required for the Synthesis of Suberin in Seed Coat and Root of Arabidopsis
Authors: Beisson Fred , Li Yonghua , Bonaventure Gustavo , Pollard Mike , Ohlrogge John B. 
Published: January 2007

Abstract
Suberin and cutin are fatty acid– and glycerol-based plant polymers that act as pathogen barriers and function in the control of water and solute transport. However, despite important physiological roles, their biosynthetic pathways, including the acyl transfer reactions, remain hypothetical. We report the characterization of two suberin mutants (gpat5-1 and gpat5-2) of Arabidopsis thaliana GPAT5, encoding a protein with acyl-CoA:glycerol-3-phosphate acyltransferase activity. RT-PCR and β-glucuronidase–promoter fusion analyses demonstrated GPAT5 expression in seed coat, root, hypocotyl, and anther. The gpat5 plants showed a 50% decrease in aliphatic suberin in young roots and produced seed coats with a severalfold reduction in very long chain dicarboxylic acid and ω-hydroxy fatty acids typical of suberin but no change in the composition or content of membrane or storage glycerolipids or surface waxes. Consistent with their altered suberin, seed coats of gpat5 mutants had a steep increase in permeability to tetrazolium salts compared with wild-type seed coats. Furthermore, the germination rate of gpat5 seeds under high salt was reduced, and gpat5 seedlings had lower tolerance to salt stress. These results provide evidence for a critical role of GPAT5 in polyester biogenesis in seed coats and roots and for the importance of lipid polymer structures in the normal function of these organs.
SDG714, a Histone H3K9 Methyltransferase, Is Involved in Tos17 DNA Methylation and Transposition in Rice
Authors: Ding Yong , Wang Xia , Su Lei , Zhai JiXian , Cao ShouYun , Zhang DongFen , Liu ChunYan , Bi YuPing , Qian Qian , Cheng ZhuKuan , Chu ChengCai , Cao XiaoFeng 
Published: January 2007

Abstract
Although the role of H3K9 methylation in rice (Oryza sativa) is unclear, in Arabidopsis thaliana the loss of histone H3K9 methylation by mutation of Kryptonite [also known as SU(VAR)3-9 homolog] reduces genome-wide DNA methylation and increases the transcription of transposable elements. Here, we report that rice SDG714 (for SET Domain Group Protein714) encodes a histone H3K9-specific methyltransferase. The C terminus of SDG714 confers enzymatic activity and substrate specificity, whereas the N terminus localizes it in the nucleus. Loss-of-function mutants of SDG714 (SDG714IR transformants) generated by RNA interference display a mostly glabrous phenotype as a result of the lack of macro trichomes in glumes, leaves, and culms compared with control plants. These mutants also show decreased levels of CpG and CNG cytosine methylation as well as H3K9 methylation at the Tos17 locus, a copia-like retrotransposon widely used for the generation of rice mutants. Most interestingly, loss of function of SDG714 can enhance transcription and cause the transposition of Tos17. Together, these results suggest that histone H3K9 methylation mediated by SDG714 is involved in DNA methylation, the transposition of transposable elements, and genome stability in rice.
Stomatal Development and Patterning Are Regulated by Environmentally Responsive Mitogen-Activated Protein Kinases inArabidopsis
Authors: Wang Huachun , Ngwenyama Njabulo , Liu Yidong , Walker John C. , Zhang Shuqun 
Published: January 2007

AbstractStomata are specialized epidermal structures that regulate gas (CO2 and O2) and water vapor exchange between plants and their environment. In Arabidopsis thaliana, stomatal development is preceded by asymmetric cell divisions, and stomatal distribution follows the one-cell spacing rule, reflecting the coordination of cell fate specification. Stomatal development and patterning are regulated by both genetic and environmental signals. Here, we report that Arabidopsis MITOGEN-ACTIVATED PROTEIN KINASE3 (MPK3) and MPK6, two environmentally responsive mitogen-activated protein kinases (MAPKs), and their upstream MAPK kinases, MKK4 and MKK5, are key regulators of stomatal development and patterning. Loss of function of MKK4/MKK5 or MPK3/MPK6 disrupts the coordinated cell fate specification of stomata versus pavement cells, resulting in the formation of clustered stomata. Conversely, activation of MKK4/MKK5-MPK3/MPK6 causes the suppression of asymmetric cell divisions and stomatal cell fate specification, resulting in a lack of stomatal differentiation. We further establish that the MKK4/MKK5-MPK3/MPK6 module is downstream of YODA, a MAPKKK. The establishment of a complete MAPK signaling cascade as a key regulator of stomatal development and patterning advances our understanding of the regulatory mechanisms of intercellular signaling events that coordinate cell fate specification during stomatal development.
Characterization of
Campylobacter jejuni
Biofilms under Defined Growth Conditions
Authors: Reeser Ryan J. , Medler Robert T. , Billington Stephen J. , Jost B. Helen , Joens Lynn A. 
Published: January 2007

ABSTRACT

Campylobacter jejuni
is a major cause of human diarrheal disease in many industrialized countries and is a source of public health and economic burden.
C. jejuni
, present as normal flora in the intestinal tract of commercial broiler chickens and other livestock, is probably the main source of human infections. The presence of
C. jejuni
in biofilms found in animal production watering systems may play a role in the colonization of these animals. We have determined that
C. jejuni
can form biofilms on a variety of abiotic surfaces commonly used in watering systems, such as acrylonitrile butadiene styrene and polyvinyl chloride plastics. Furthermore,
C. jejuni
biofilm formation was inhibited by growth in nutrient-rich media or high osmolarity, and thermophilic and microaerophilic conditions enhanced biofilm formation. Thus, nutritional and environmental conditions affect the formation of
C. jejuni
biofilms. Both flagella and quorum sensing appear to be required for maximal biofilm formation, as
C. jejuni flaAB
and
luxS
mutants were significantly reduced in their ability to form biofilms compared to the wild-type strain.
Inactivation of Influenza A Virus on Copper versus Stainless Steel Surfaces
Authors: Noyce J. O. , Michels H. , Keevil C. W. 
Published: January 2007

ABSTRACT

Influenza A virus particles (2 × 10
6
) were inoculated onto copper or stainless steel and incubated at 22°C at 50 to 60% relative humidity. Infectivity of survivors was determined by utilizing a defined monolayer with fluorescent microscopy analysis. After incubation for 24 h on stainless steel, 500,000 virus particles were still infectious. After incubation for 6 h on copper, only 500 particles were active.
Characterization of the Population of the Sulfur-Oxidizing Symbiont ofCodakia orbicularis(Bivalvia, Lucinidae) by Single-Cell Analyses
Authors: Caro Audrey , Gros Olivier , Got Patrice , De Wit Rutger , Troussellier Marc 
Published: January 2007

ABSTRACTWe investigated the characteristics of the sulfur-oxidizing symbiont hosted in the gills ofCodakia orbicularis, a bivalve living in shallow marine tropical environments. Special attention was paid to describing the heterogeneity of the population by using single-cell approaches including flow cytometry (FCM) and different microscopic techniques and by analyzing a cell size fractionation experiment. Up to seven different subpopulations were distinguished by FCM based on nucleic acid content and light side scattering of the cells. The cell size analysis of symbionts showed that the symbiotic population was very heterogeneous in size, i.e., ranging from 0.5 to 5 μm in length, with variable amounts of intracellular sulfur. The side-scatter signal analyzed by FCM, which is often taken as a proxy of cell size, was greatly influenced by the sulfur content of the symbionts. FCM revealed an important heterogeneity in the relative nucleic acid content among the subclasses. The larger cells contained exceptionally high levels of nucleic acids, suggesting that these cells contained multiple copies of their genome, i.e., ranging from one copy for the smaller cells to more than four copies for the larger cells. The proportion of respiring symbionts (5-cyano-2,3-ditolyl-terazolium chloride positive) in the bacteriocytes ofCodakiarevealed that around 80% of the symbionts hosted byCodakiamaintain respiratory activity throughout the year. These data allowed us to gain insight into the functioning of the symbionts within the host and to propose some hypotheses on how the growth of the symbionts is controlled by the host.