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Involvement of C4 Protein of Beet Severe Curly Top Virus (Family Geminiviridae) in Virus Movement  [PDF]
Kunling Teng,Hao Chen,Jianbin Lai,Zhonghui Zhang,Yuanyuan Fang,Ran Xia,Xueping Zhou,Huishan Guo,Qi Xie
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0011280
Abstract: Beet severe curly top virus (BSCTV) is a leafhopper transmitted geminivirus with a monopartite genome. C4 proteins encoded by geminivirus play an important role in virus/plant interaction.
Molecular characterization and construction of an infectious clone of a pepper isolate of Beet curly top Iran virus
Omid Eini; Ghazal Ebadzad-Sahraei; Seyed Ali Akbar Behjatnia
Molecular Biology Research Communications , 2016,
Abstract: Geminiviruses cause curly top disease, in dicotyledonous plants which constrains host crop production. Beet curly top Iran virus (BCTIV) is a widespread Becurtovirus (family Geminiviridae) in numerous areas within Iran. In this study, we isolated and analyzed a full-length genomic DNA of a new variant of BCTIV from pepper crops in the Kaftark region, east of Shiraz (proposed acronym: BCTIV-Kaf [IR: Kaf:2016:Pepper]). Infected pepper plants showed shortening of internodes, severe interveinal chlorosis, upward leaf rolling and leaf curling. Sequence and phylogenetic analysis showed this BCTIV variant grouped with sugar beet isolates of BCTIV and has the highest similarity to a sugar beet BCTIV isolate from Negar town in Kerman province, Iran. It was more distantly related to a bean isolate of BCTIV from northeast region of Iran. A tandem repeat partial dimmer of BCTIV was constructed and found to be infectious in pepper, tomato and Nicotiana benthamiana plants. Results of this study indicated that BCTIV-Kaf is a new variant of BCTIV infecting pepper plants in Shiraz and that geographic location rather than the type of host plant has more effect on genetic diversity of BCTIV in Iran.
Viable chimaeric viruses confirm the biological importance of sequence specific maize streak virus movement protein and coat protein interactions
Eric van der Walt, Kenneth E Palmer, Darren P Martin, Edward P Rybicki
Virology Journal , 2008, DOI: 10.1186/1743-422x-5-61
Abstract: Using chimaeric genomes of two strains of Maize streak virus (MSV) we adopted a genetic approach to investigate the gross biological effects of interfering with interactions between virus MP and CP homologues derived from genetically distinct MSV isolates. MP and CP genes were reciprocally exchanged, individually and in pairs, between maize (MSV-Kom)- and Setaria sp. (MSV-Set)-adapted isolates sharing 78% genome-wide sequence identity. All chimaeras were infectious in Zea mays c.v. Jubilee and were characterized in terms of symptomatology and infection efficiency. Compared with their parental viruses, all the chimaeras were attenuated in symptom severity, infection efficiency, and the rate at which symptoms appeared. The exchange of individual MP and CP genes resulted in lower infection efficiency and reduced symptom severity in comparison with exchanges of matched MP-CP pairs.Specific interactions between the mastrevirus MP and CP genes themselves and/or their expression products are important determinants of infection efficiency, rate of symptom development and symptom severity.Mutation studies are often employed in attempts to identify the genetic basis of important aspects of a pathogen's phenotype. For example, in order to understand the genomic determinants of pathogenicity, genetic elements may be altered in, deleted from, or exchanged between virulent and benign pathogen isolates. During the last two decades, molecular biologists studying the ssDNA geminiviruses (family: Geminiviridae) have made extensive use of intra- and intergeneric genetic exchange in a wide variety of experiments. Briddon et al. [1] replaced the coat protein gene of the whitefly-transmitted African cassava mosaic begomovirus (ACMV) with that of beet curly top curtovirus (BCTV) and successfully transmitted the recombinant ACMV via the BCTV-specific leafhopper vector Circulifer renellus (Baker), thereby demonstrating that insect vector specificity for geminiviruses is determined by the co
Curly Encodes Dual Oxidase, Which Acts with Heme Peroxidase Curly Su to Shape the Adult Drosophila Wing  [PDF]
Thomas Ryan Hurd?,Feng-Xia Liang?,Ruth Lehmann
PLOS Genetics , 2015, DOI: 10.1371/journal.pgen.1005625
Abstract: Curly, described almost a century ago, is one of the most frequently used markers in Drosophila genetics. Despite this the molecular identity of Curly has remained obscure. Here we show that Curly mutations arise in the gene dual oxidase (duox), which encodes a reactive oxygen species (ROS) generating NADPH oxidase. Using Curly mutations and RNA interference (RNAi), we demonstrate that Duox autonomously stabilizes the wing on the last day of pupal development. Through genetic suppression studies, we identify a novel heme peroxidase, Curly Su (Cysu) that acts with Duox to form the wing. Ultrastructural analysis suggests that Duox and Cysu are required in the wing to bond and adhere the dorsal and ventral cuticle surfaces during its maturation. In Drosophila, Duox is best known for its role in the killing of pathogens by generating bactericidal ROS. Our work adds to a growing number of studies suggesting that Duox’s primary function is more structural, helping to form extracellular and cuticle structures in conjunction with peroxidases.
Standardized production of Phyllanthus tenellus Roxb. by plant tissue culture
Victório, Cristiane Pimentel;Henriques, Anaize Borges;Tavares, Eliana Schwartz;Esquibel, Maria Apparecida;Lage, Celso Luiz Salgueiro;
Revista Ciência Agron?mica , 2010, DOI: 10.1590/S1806-66902010000200015
Abstract: exigencies as ethic plant raw material are part of the needs of modern phytotherapy. micropropagation offers opportunities to obtain mass propagation of superior genotypes in short time. this study aimed to develop a protocol of direct and indirect organogenesis of phyllanthus tenellus roxb. nodal segments from plantlets obtained by in vitro germination were subcultured in modified murashige and skoog medium added with different plant growth regulators: iaa (indole-3-acetic acid), iba (indole-3-butyric acid), ga3 (3-giberelic acid) and kin (kinetin). the highest proliferation rate was obtained using the combinations: iba, kin + ga3 (3.5 mg l-1) and iba + kin (2.4 mg l-1). rooting was intensified after 40 days, reaching 100% for all media with indole-3-butyric acid. addition of 2,4 dichlorophenoxyacetic acid (2,4d) provided the best results for production of friable calli. acclimatization was 100% effective for plantlets cultured in control medium, with decrease in survival rate in grown plantlets from media added with growth regulators.
Some examples of Baker domains  [PDF]
Walter Bergweiler,Jian-Hua Zheng
Mathematics , 2011, DOI: 10.1088/0951-7715/25/4/1033
Abstract: We construct entire functions with hyperbolic and simply parabolic Baker domains on which the functions are not univalent. The Riemann maps from the unit disk to these Baker domains extend continuously to certain arcs on the unit circle. The results answer questions posed by Fagella and Henriksen, Baker and Dominguez, and others.
Influência da colora??o das sementes na germina??o de Phyllanthus tenellus Roxb. e Phyllanthus niruri L. (Euphorbiaceae)
Venturi, Silvia;Randi, áurea Maria;
Acta Botanica Brasilica , 1997, DOI: 10.1590/S0102-33061997000100009
Abstract: heteromorphy was observed in phyllanthus tenellus and p. niruri seeds. there are two kinds of seeds: brown and yellow. there is variation in the number of the two kinds of seeds harvested in different periods of the year. brown seeds present higher mass and higher percentage of germination. proteins and soluble sugars were also analysed in p. niruri seeds and the highest level of these storage substances was found in seeds harvested in late spring. in p. niruri the level of protein and soluble sugars was smaller in the sample harvested in autumn, but no alteration was seen in seed mass. seed germination of the autumn collection was smaller than the spring collection. soluble sugars level was higher in yellow seeds of p. niruri and in brown seeds of p. tenellus. brown seeds germination was higher under continuous white light. after 10 months of storage at ± 4oc the germinability of the p. tenellus brown seeds decreased about 50%.
Estudo da toxicidade subcr nica de phyllanthus tenellus roxb.: avalia o comportamental
Tássia Campos de Lima e Silva, Ivone Ant?nia de Souza, Ednaldo Cavalcante de Araújo, Elba Lúcia Cavalcanti de Amorim,Tiago de Lima Barros Gomes,Jorge Veras Filho.
Revista de Enfermagem UFPE On Line , 2008,
Abstract: In absence of studies that support a satisfactory toxicological control, it was objective of this research to evaluate the behaviors alterations in mice from subchronic toxicity studies of the hydroalcoolic extract of Phyllanthus tenellus Roxb. Daily expositions in mice of the extract of Phyllanthus tenellus had been fulfilled by intraperitoneous injection way in 60 days. Three groups from five mice previously marked, weighed and kept the cares of feeding, illumination had been used and room. The groups had been divided in G1 (managed the extract 125mg/kg of the animal), G2 (managed the extract 250mg/kg of the animal) and G3 (group has controlled, being managed only solution physiological 0.9% of NaCl), evaluating daily the mice regarding to toxicity signals. Behaviors alterations for the two established doses had been observed, however the group that received the biggest dose suffered to greaters alterations being most important: respiratory frequency reduction, prostration, edema of snout, piloerection, hydrocele and death, thus considering the toxic plant for subchronic use depending on its used concentration.
The Repetitive Domain of ScARP3d Triggers Entry of Spiroplasma citri into Cultured Cells of the Vector Circulifer haematoceps  [PDF]
Laure Béven, Sybille Duret, Brigitte Batailler, Marie-Pierre Dubrana, Colette Saillard, Jo?l Renaudin, Nathalie Arricau-Bouvery
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048606
Abstract: Spiroplasma citri is a plant pathogenic mollicute transmitted by the leafhopper vector Circulifer haematoceps. Successful transmission requires the spiroplasmas to cross the intestinal epithelium and salivary gland barriers through endocytosis mediated by receptor-ligand interactions. To characterize these interactions we studied the adhesion and invasion capabilities of a S. citri mutant using the Ciha-1 leafhopper cell line. S. citri GII3 wild-type contains 7 plasmids, 5 of which (pSci1 to 5) encode 8 related adhesins (ScARPs). As compared to the wild-type strain GII3, the S. citri mutant G/6 lacking pSci1 to 5 was affected in its ability to adhere and enter into the Ciha-1 cells. Proteolysis analyses, Triton X-114 partitioning and agglutination assays showed that the N-terminal part of ScARP3d, consisting of repeated sequences, was exposed to the spiroplasma surface whereas the C-terminal part was anchored into the membrane. Latex beads cytadherence assays showed the ScARP3d repeat domain (Rep3d) to be involved, and internalization of the Rep3d-coated beads to be actin-dependent. These data suggested that ScARP3d, via its Rep3d domain, was implicated in adhesion of S. citri GII3 to insect cells. Inhibition tests using anti-Rep3d antibodies and competitive assays with recombinant Rep3d both resulted in a decrease of insect cells invasion by the spiroplasmas. Unexpectedly, treatment of Ciha-1 cells with the actin polymerisation inhibitor cytochalasin D increased adhesion and consequently entry of S. citri GII3. For the ScARPs-less mutant G/6, only adhesion was enhanced though to a lesser extent following cytochalasin D treatment. All together these results strongly suggest a role of ScARPs, and particularly ScARP3d, in adhesion and invasion of the leafhopper cells by S. citri.
Two new plumage mutations in the Japanese quail: "curly" feather and "rusty" plumage
Francis Minvielle, David Gourichon, Chantal Moussu
BMC Genetics , 2005, DOI: 10.1186/1471-2156-6-14
Abstract: Curly feathers result from abnormal early growth caused by transient joining of follicle walls of adjacent feathers around 10 days of age, but the expression of the trait is variable. Rusty plumage color results from the replacement of the wild-type plumage pattern on the tip of the feather by a reddish coloration, but the pigmentation of the bottom part of the feather is not affected. Two lines breeding true for the curly or the rusty phenotype were developed. Both characters are determined by autosomal recessive mutations which are independent. The curly mutation has also a positive effect on body weight at 5 weeks of age.The curly line is a new model which may be used for further work on the growth of the feather, and the rusty mutation is a new addition to the panel of plumage mutations available for comparative studies in poultry, and more generally among avian species.Japanese quail is both a model animal in biology and a bird used for meat and egg production under a large variety of settings [1]. In the recent past, a special attention was given to the study of its plumage, and several major genes have been described [2]. Since the last compilation of plumage mutations of Japanese quail [2], new loci were described [e.g. [3]], linkage and epistasis relationships were explored [4,5], and some genes were recently mapped [6]. This knowledge has already been put to use for running comparisons between chicken and quail based on plumage genetics [7,8], and for tagging commercial quail lines with a visible plumage trait, like the "fawn" mutation [9], or with an auto-sexing mutation like the "roux" gene [10]. Interestingly, some of the mutations described in quail, like the sex-linked "roux" and the lethal "yellow" mutations still have no known homologues in the chicken. Moreover, the fact that some plumage colors, like "lavender", are common to several avian species [5] is an added incentive to enrich the panel of characterised Japanese quail mutations as potential
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