Endochitinases are widely distributed among higher plants, including a number of important crop species. They are generally considered to be involved in plant defence against potential pathogens. We have cloned a class IV chitinase gene (AtchitIV) from Arabidopsis thaliana. Southern blot analysis allowed the detection of two cross-hybridising genes in the A. thaliana genome. AtchitIV transcripts are detected in seedpods, but not in roots, inflorescence stems, leaves and flowers of healthy plants. The transcripts accumulated very rapidly in leaves after inoculation with Xanthomonas campestris. Maximum mRNA accumulation was reached one hour after infection and decreased to very low levels 72 hours after induction. This result suggests an involvement of AtchitIV in the initial events of the hypersensitive reaction. Nevertheless, A. thaliana plants transformed with the gus gene under the control of a class IV chitinase bean promoter, showed GUS activity in seed embryos. These data, together with the constitutive expression of the endogenous gene in the seedpods, points to additional physiological roles for this protein.
RESUMO.-[Eimeria spp. de codornas japonesas (Coturnix japonica): novas características e ferramentas de diagnóstico.] A codorna japonesa Coturnix japonica originária do norte da África, Europa e Ásia, é utilizada mundialmente como um animal experimental e modelo para avicultura. O presente trabalho caracteriza Eimeria bateri, Eimeria tsunodai e Eimeria uzura recuperadas de C. japonica. Baseado no fato de que as codornas têm uma distribuição global, como são os seus coccídios, os resultados deste estudo devem propiciar o diagnóstico destas Eimeria spp. em outras regiões e continentes. Eimeria bateri demonstrou a maior intensidade de infecção e eliminaram oocistos a partir do quarto dia após infecção, em contraste E. tsunodai e E. uzura eliminaram oocistos a partir do quinto dia após infecção. As três espécies foram morfometricamente semelhantes e polimórficas. No entanto, a aplicação da regressão linear, histogramas e ANOVA proveram meios para a identificação destas espécies. Finalmente, o algoritmo foi totalmente eficiente uma vez que valores resultantes não foram sobrepostos. TERMOS DE INDEXAÇÃO: Coccidiose, diagnóstico, Eimeria bateri, Eimeria tsunodai, Eimeria uzura. INTRODUCTIONThe breeding of Japanese quails Coturnix japonica has excelled in aviculture, due to increased consumption of exotic meats and eggs, and represents an alternative to chicken production. In the USA, Japanese quails were introduced in the 1950s, and at that time the breeding of Japanese quails was already widespread in European countries. In Brazil, Japanese quails were introduced in the 1950s, but large scale production began in the mid 1960's (Howes 1964, Murakami & Ariki 1998, IUCN 2013, Jatoi et al. 2013.In addition to its importance for aviculture, the Japanese quail has become, in recent decades, an important experimental animal for scientific research. It is used extensively in studies examining genetics, nutrition, toxicology, em- The Japanese quail Coturnix japonica originated from North Africa, Europe and Asia, is used worldwide as an experimental animal and model for aviculture. The current paper characterizes Eimeria bateri, Eimeria tsunodai and Eimeria uzura recovered from C. japonica. Based on the fact that quails have a global distribution, as are their coccidia, the findings of this study should provide the means for diagnosis of those Eimeria spp. in other regions and continents. Eimeria bateri showed the greatest intensity of infection and shed oocysts from the fourth day after infection; in contrast, E. tsunodai and E. uzura shed oocysts from the fifth day after infection. The three species shared a high degree of similarity and were all polymorphic. Yet, the application of line regressions, histograms and ANOVA provided means for the identification of these species. Finally, the algorithm was very efficient since verified that resultant values were not superimposed.
A species of Isospora Schneider, 1881 (Protozoa: Apicomplexa: Eimeriidae) considered as new to science is described and characterised molecularly from the eastern white-throated spadebill Platyrinchus mystaceus Vieillot in the Parque Nacional do Itatiaia, southeastern Brazil. Isospora lopesi n. sp. has oöcysts that are subspheroidal to ovoidal, 18-24 × 18-22 (20.6 × 19.7) µm, with smooth, bilayered wall, c.1.5 μm thick. Micropyle and oöcyst residuum are absent, but one polar granule is present. Sporocysts are ellipsoidal, 12-16 × 8-11 (14.4 × 8.6) µm. The Stieda body is flattened to half-moon-shaped and sub-Stieda body is rounded. Sporocyst residuum is present, consisting of numerous spherules of different sizes. Sporozoites are vermiform with anterior and posterior refractile bodies and nucleus. Molecular analysis was conducted at the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This new isolate exhibited similarity greater than 98% with Isospora spp. isolates from spectacled warblers Sylvia conspicillata Temminck, 1820. This is the fourth isosporoid coccidian described from New World tyrannid birds, but is the first to have a complementary molecular characterisation.
To investigate how PvChi4 promoter regulates gene expression during plant development and in response to stress, we have introduced promoter-GUS transcriptional fusion constructs in transgenic Arabidopsis thaliana and tobacco plants. GUS activity was not detected in aerial vegetative organs of transgenic plants carrying the 2189 bp promoter. However, gus expression was activated at the parenchyma and epidermis of leaves and stem, when these transgenic tobacco plants were submitted to heat shock and UV irradiation. The non-stressed plants showed promoter activity in the meristematic region of lateral roots and in reproductive organs. In both species, the promoter was active in pollen grains and ovaries. In tobacco anthers, gus expression was observed in the middle layer. In transgenic plants harbouring promoters of 1445 bp, 1199 bp, 501 bp and 416 bp, GUS activity has been detected, in addition to the meristematic
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.