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21.
Characterization of the expression of a wheat cystatin gene during caryopsis development 总被引:6,自引:0,他引:6
Corr-Menguy F Cejudo FJ Mazubert C Vidal J Lelandais-Brière C Torres G Rode A Hartmann C 《Plant molecular biology》2002,50(4-5):687-698
A cDNA coding for phytocystatin, a protease inhibitor, was isolated from wheat embryos by differential display RT-PCR and the corresponding full-length cDNA (named WC5 for wheat cystatin gene 5) subsequently obtained by RACE. The deduced primary sequence of the protein suggests the presence of a 28 amino acid N-terminal signal sequence and a 100 amino acid mature protein containing the three consensus motifs known to interact with the active site of cysteine peptidases. Northern and western analysis revealed a spatio-temporal pattern of the cystatin gene expression during caryopse development. In the embryo, WC5 was only expressed during early embryogenesis whereas, in seed covering layers, WC5 expression was restricted to the maturation stage of grain development. In addition, immunolocalization experiments showed that cystatin accumulated in the aleurone layer of the maturating seed and in the parenchymal tissues of the embryo scutellum. A recombinant form of the wheat cystatin was shown to be able to inhibit peptidase activities present in whole seed protein extracts. In addition, immunological techniques allowed us to identify two putative target peptidases. The possible roles of the cystatin protein are discussed in relation with tissular localization and putative peptidase targets during seed maturation. 相似文献
22.
Mariana Malzoni Furtado Solange Maria Gennari Cassia Yumi Ikuta Anah Tereza de Almeida Jácomo Zenaide Maria de Morais Hilda Fátima de Jesus Pena Grasiela Edith de Oliveira Porfírio Leandro Silveira Rahel Sollmann Gisele Oliveira de Souza Natália Mundim T?rres José Soares Ferreira Neto 《PloS one》2015,10(11)
This study investigated the exposure of jaguar populations and domestic animals to smooth Brucella, Leptospira spp. and Toxoplasma gondii in the Cerrado, Pantanal and Amazon biomes of Brazil. Between February 2000 and January 2010, serum samples from 31 jaguars (Panthera onca), 1,245 cattle (Bos taurus), 168 domestic dogs (Canis lupus familiaris) and 29 domestic cats (Felis catus) were collected and analysed by rose bengal test for smooth Brucella, microscopic agglutination test for Leptospira spp. and modified agglutination test for T. gondii. Cattle populations from all sites (9.88%) were exposed to smooth Brucella, but only one jaguar from Cerrado was exposed to this agent. Jaguars captured in the Cerrado (60.0%) and in the Pantanal (45.5%) were seropositive for different serovars of Leptospira spp., cattle (72.18%) and domestic dogs (13.1%) from the three sites and one domestic cat from Pantanal were also seropositive for the agent. The most prevalent serotype of Leptospira spp. identified in jaguars from the Cerrado (Grippotyphosa) and the Pantanal (Pomona) biomes were distinct from those found in the domestic animals sampled. Jaguars (100%), domestic dogs (38.28%) and domestic cats (82.76%) from the three areas were exposed to T. gondii. Our results show that brucellosis and leptospirosis could have been transmitted to jaguars by domestic animals; and jaguars probably play an important role in the maintenance of T. gondii in nature. 相似文献
23.
Karina Tuz Ruxandra Bachmann-Gagescu Diana?R. O’Day Kiet Hua Christine?R. Isabella Ian?G. Phelps Allan?E. Stolarski Brian?J. O’Roak Jennifer?C. Dempsey Charles Lourenco Abdulrahman Alswaid Carsten?G. B?nnemann Livija Medne Sheela Nampoothiri Zornitza Stark Richard?J. Leventer Meral Top?u Ali Cansu Sujatha Jagadeesh Stephen Done Gisele?E. Ishak Ian?A. Glass Jay Shendure Stephan?C.F. Neuhauss Chad?R. Haldeman-Englert Dan Doherty Russell?J. Ferland 《American journal of human genetics》2014,94(1):62-72
Joubert syndrome (JBTS) is a recessive ciliopathy in which a subset of affected individuals also have the skeletal dysplasia Jeune asphyxiating thoracic dystrophy (JATD). Here, we have identified biallelic truncating CSPP1 (centrosome and spindle pole associated protein 1) mutations in 19 JBTS-affected individuals, four of whom also have features of JATD. CSPP1 mutations explain ∼5% of JBTS in our cohort, and despite truncating mutations in all affected individuals, the range of phenotypic severity is broad. Morpholino knockdown of cspp1 in zebrafish caused phenotypes reported in other zebrafish models of JBTS (curved body shape, pronephric cysts, and cerebellar abnormalities) and reduced ciliary localization of Arl13b, further supporting loss of CSPP1 function as a cause of JBTS. Fibroblasts from affected individuals with CSPP1 mutations showed reduced numbers of primary cilia and/or short primary cilia, as well as reduced axonemal localization of ciliary proteins ARL13B and adenylyl cyclase III. In summary, CSPP1 mutations are a major cause of the Joubert-Jeune phenotype in humans; however, the mechanism by which these mutations lead to both JBTS and JATD remains unknown. 相似文献
24.
G Junior DS Araújo FR Almeida Junior NF Adi SS Cheung LM Fragoso SP Ramos CA Oliveira RH Santos CS Bacanelli G Soares CO Rosinha GM Fonseca AH 《Memórias do Instituto Oswaldo Cruz》2010,105(7):843-849
The sequencing of the complete genome of Anaplasma marginale has enabled the identification of several genes that encode membrane proteins, thereby increasing the chances of identifying candidate immunogens. Little is known regarding the genetic variability of genes that encode membrane proteins in A. marginale isolates. The aim of the present study was to determine the degree of conservation of the predicted amino acid sequences of OMP1, OMP4, OMP5, OMP7, OMP8, OMP10, OMP14, OMP15, SODb, OPAG1, OPAG3, VirB3, VirB9-1, PepA, EF-Tu and AM854 proteins in a Brazilian isolate of A. marginale compared to other isolates. Hence, primers were used to amplify these genes: omp1, omp4, omp5, omp7, omp8, omp10, omp14, omp15, sodb, opag1, opag3, virb3, VirB9-1, pepA, ef-tu and am854. After polimerase chain reaction amplification, the products were cloned and sequenced using the Sanger method and the predicted amino acid sequence were multi-aligned using the CLUSTALW and MEGA 4 programs, comparing the predicted sequences between the Brazilian, Saint Maries, Florida and A. marginale centrale isolates. With the exception of outer membrane protein (OMP) 7, all proteins exhibited 92-100% homology to the other A. marginale isolates. However, only OMP1, OMP5, EF-Tu, VirB3, SODb and VirB9-1 were selected as potential immunogens capable of promoting cross-protection between isolates due to the high degree of homology (over 72%) also found with A. (centrale) marginale. 相似文献
25.
Ana-Carolina Oliveira Bruna C. de Alencar Fanny Tzelepis Weberton Klezewsky Raquel N. da Silva Fabieni S. Neves Gisele S. Cavalcanti Silvia Boscardin Marise P. Nunes Marcelo F. Santiago Alberto Nóbrega Maurício M. Rodrigues Maria Bellio 《PLoS pathogens》2010,6(4)
The murine model of T. cruzi infection has provided compelling evidence that development of host resistance against intracellular protozoans critically depends on the activation of members of the Toll-like receptor (TLR) family via the MyD88 adaptor molecule. However, the possibility that TLR/MyD88 signaling pathways also control the induction of immunoprotective CD8+ T cell-mediated effector functions has not been investigated to date. We addressed this question by measuring the frequencies of IFN-γ secreting CD8+ T cells specific for H-2Kb-restricted immunodominant peptides as well as the in vivo Ag-specific cytotoxic response in infected animals that are deficient either in TLR2, TLR4, TLR9 or MyD88 signaling pathways. Strikingly, we found that T. cruzi-infected Tlr2−/−, Tlr4−/−, Tlr9−/
− or Myd88−/− mice generated both specific cytotoxic responses and IFN-γ secreting CD8+ T cells at levels comparable to WT mice, although the frequency of IFN-γ+CD4+ cells was diminished in infected Myd88−/− mice. We also analyzed the efficiency of TLR4-driven immune responses against T. cruzi using TLR4-deficient mice on the C57BL genetic background (B6 and B10). Our studies demonstrated that TLR4 signaling is required for optimal production of IFN-γ, TNF-α and nitric oxide (NO) in the spleen of infected animals and, as a consequence, Tlr4−/− mice display higher parasitemia levels. Collectively, our results indicate that TLR4, as well as previously shown for TLR2, TLR9 and MyD88, contributes to the innate immune response and, consequently, resistance in the acute phase of infection, although each of these pathways is not individually essential for the generation of class I-restricted responses against T. cruzi. 相似文献
26.
Genetic variability in nodulation and root growth affects nitrogen fixation and accumulation in pea 总被引:1,自引:0,他引:1
BACKGROUND AND AIMS: Legume nitrogen is derived from two different sources, symbiotically fixed atmospheric N(2) and soil N. The effect of genetic variability of root and nodule establishment on N acquisition and seed protein yield was investigated under field conditions in pea (Pisum sativum). In addition, these parameters were related to the variability in preference for rhizobial genotypes. METHODS: Five different spring pea lines (two hypernodulating mutants and three cultivars), previously identified in artificial conditions as contrasted for both root and nodule development, were characterized under field conditions. Root and nodule establishment was examined from the four-leaf stage up to the beginning of seed filling and was related to the patterns of shoot dry matter and nitrogen accumulation. The genetic structure of rhizobial populations associated with the pea lines was obtained by analysis of nodule samples. The fraction of nitrogen derived from symbiotic fixation was estimated at the beginning of seed filling and at physiological maturity, when seed protein content and yield were determined. KEY RESULTS: The hypernodulating mutants established nodules earlier and maintained them longer than was the case for the three cultivars, whereas their root development and nitrogen accumulation were lower. The seed protein yield was higher in 'Athos' and 'Austin', the two cultivars with increased root development, consistent with their higher N absorption during seed filling. CONCLUSION: The hypernodulating mutants did not accumulate more nitrogen, probably due to the C cost for nodulation being higher than for root development. Enhancing exogenous nitrogen supply at the end of the growth cycle, by increasing the potential for root N uptake from soil, seems a good option for improving pea seed filling. 相似文献
27.
Venturini J Golim MA Alvares AM Locachevic GA Arruda OS Arruda MS 《FEMS immunology and medical microbiology》2011,62(1):32-40
Many works have shown that the enhanced susceptibility to infection seen in diabetic patients can be related to the hyperglycemia-hypoinsulinemia (HH) observed in this condition. Herein, we evaluated the HH effects on the morphofunctional features of the thymus as well as on dermatophytic infection. We demonstrated that, not only the HH condition but also the dermatophytic infection induced transitory alterations in the thymus; it was characterized by loss of cortical-medullar definition and disorganization of the extracellular matrix. These mice also showed a decrease of CD4(+) CD8(+) thymocytes and a higher percentage of CD4(+) CD8(+) lymphocytes in the peripheral blood. After 7 days, the thymus and peripheral lymphocytes subsets returned to normal values. Interestingly, when the two conditions, HH condition and the infection, were associated, the mice showed a decrease in the percentage of CD4(+) CD8(-) blood lymphocytes that are involved in the modulation of immune response and have direct cytotoxic effects on the fungus. Taken together, our results showed that both conditions transitorily changed the thymus, but only when both these conditions are present do they trigger persistent changes that might be responsible for the higher susceptibility to dermatophytosis seen in HH patients. 相似文献
28.
Mingoti GZ Castro VS Méo SC Sá Barretto LS Garcia JM 《In vitro cellular & developmental biology. Animal》2011,47(5-6):361-367
Aiming to standardize in vitro production of bovine embryos and to obtain supplements to replace serum in culture media, this study evaluated the nuclear maturation kinetics and embryonic development in bovine after in vitro maturation (IVM) and culture (IVC) with several macromolecules (animal origin: bovine serum albumin (BSA), fetal calf serum (FCS); synthetic: polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), Ficoll, and Knockout) at two oxygen tensions (20% and 5% O(2)). Regarding nuclear kinetics, neither the presence of the expected stage (metaphase I, transition anaphase to telophase, and metaphase II) at each evaluation moment (6, 18, and 24?h after IVM, respectively) nor the accelerated polar body emission (at 18?h after IVM) related developmental competence to blastocyst stage when different supplements were compared. Independently of supplement, cleavage rates at 20% O(2) (61.6-79.2%) were higher than at 5% O(2) (38.9-58.7%). At 20% O(2), higher blastocyst and hatching rates, respectively, were obtained in treatments BSA, FCS, Knockout, and control group (IVM with FCS and IVC with BSA + FCS, 14.0-23.5% and 6.8-15.4%) in comparison to PVA, PVP, and Ficoll (0%). The same was observed at 5% O(2) for blastocyst rates with BSA, FCS, Knockout, and control (5.4-16.8%) and for hatching rates with BSA, FCS, and control (2.0-11.1%). We can conclude that producing bovine embryos at 20% O(2) during the entire IVP process resulted in higher developmental rates than at 5% O(2). In addition, while defined macromolecules PVA, PVP, and Ficoll were not suitable for embryonic development, the synthetic serum Knockout was able to replace serum and albumin for IVP in bovine at 20% O(2). 相似文献
29.
Chin CD Laksanasopin T Cheung YK Steinmiller D Linder V Parsa H Wang J Moore H Rouse R Umviligihozo G Karita E Mwambarangwe L Braunstein SL van de Wijgert J Sahabo R Justman JE El-Sadr W Sia SK 《Nature medicine》2011,17(8):1015-1019
One of the great challenges in science and engineering today is to develop technologies to improve the health of people in the poorest regions of the world. Here we integrated new procedures for manufacturing, fluid handling and signal detection in microfluidics into a single, easy-to-use point-of-care (POC) assay that faithfully replicates all steps of ELISA, at a lower total material cost. We performed this 'mChip' assay in Rwanda on hundreds of locally collected human samples. The chip had excellent performance in the diagnosis of HIV using only 1 μl of unprocessed whole blood and an ability to simultaneously diagnose HIV and syphilis with sensitivities and specificities that rival those of reference benchtop assays. Unlike most current rapid tests, the mChip test does not require user interpretation of the signal. Overall, we demonstrate an integrated strategy for miniaturizing complex laboratory assays using microfluidics and nanoparticles to enable POC diagnostics and early detection of infectious diseases in remote settings. 相似文献
30.
Candela Iglesias Mathieu Ringeard Francesca Di Nunzio Juliette Fernandez Raphael Gaudin Philippe Souque Pierre Charneau Nathalie Arhel 《Retrovirology》2011,8(1):1-13