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101.
Immunological and metabolomic impacts of administration of Cry1Ab protein and MON 810 maize in mouse 总被引:1,自引:0,他引:1
Adel-Patient K Guimaraes VD Paris A Drumare MF Ah-Leung S Lamourette P Nevers MC Canlet C Molina J Bernard H Créminon C Wal JM 《PloS one》2011,6(1):e16346
We have investigated the immunological and metabolomic impacts of Cry1Ab administration to mice, either as a purified protein or as the Cry1Ab-expressing genetically modified (GM) MON810 maize. Humoral and cellular specific immune responses induced in BALB/cJ mice after intra-gastric (i.g.) or intra-peritoneal (i.p.) administration of purified Cry1Ab were analyzed and compared with those induced by proteins of various immunogenic and allergic potencies. Possible unintended effects of the genetic modification on the pattern of expression of maize natural allergens were studied using IgE-immunoblot and sera from maize-allergic patients. Mice were experimentally sensitized (i.g. or i.p. route) with protein extracts from GM or non-GM maize, and then anti-maize proteins and anti-Cry1Ab-induced immune responses were analyzed. In parallel, longitudinal metabolomic studies were performed on the urine of mice treated via the i.g. route. Weak immune responses were observed after i.g. administration of the different proteins. Using the i.p. route, a clear Th2 response was observed with the known allergenic proteins, whereas a mixed Th1/Th2 immune response was observed with immunogenic protein not known to be allergenic and with Cry1Ab. This then reflects protein immunogenicity in the BALB/c Th2-biased mouse strain rather than allergenicity. No difference in natural maize allergen profiles was evidenced between MON810 and its non-GM comparator. Immune responses against maize proteins were quantitatively equivalent in mice treated with MON810 vs the non-GM counterpart and no anti-Cry1Ab-specific immune response was detected in mice that received MON810. Metabolomic studies showed a slight "cultivar" effect, which represented less than 1% of the initial metabolic information. Our results confirm the immunogenicity of purified Cry1Ab without evidence of allergenic potential. Immunological and metabolomic studies revealed slight differences in mouse metabolic profiles after i.g. administration of MON810 vs its non-GM counterpart, but no significant unintended effect of the genetic modification on immune responses was seen. 相似文献
102.
Biology and fertility life table of Helicoverpa armigera (Lepidoptera: Noctuidae) in different hosts 下载免费PDF全文
In 2013, the presence of Helicoverpa armigera (Hübner) was reported in cotton, soybean, corn and weeds in diverse regions of Brazil. We studied the biology and the fertility life table of this pest when reared on cotton (293 cv. CNPA RF), soybean (cv. Brasmax Power), corn (cv. BRS 1010), wheat (cv. BR 18) and on an artificial diet. Caterpillars were reared using the vegetative and reproductive structures of the hosts, under laboratory conditions (temperature 25 ± 1°C; relative humidity (RH) 70 ± 10%; photoperiod =14 h). The experimental design was completely randomized, with five treatments (four host plants and artificial diet) and 17 replications. Significant effects were verified for the different types of hosts tested on the growth of the insect as well as on fecundity and laying rate. The results showed that cotton and soybean had higher viability at the stages of growth, higher rate of survival of adult females in the reproductive period than the other host crops, and similar values for insects reared on an artificial diet, which reveals that cotton and soybean can be appropriate for rearing H. armigera on a natural diet. Corn and wheat showed high larval and pupal mortality and low biotic potential. 相似文献
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Claire Parent Audrey Berger Nicolas Capelli Michèle Crèvecoeur James F Dat 《Plant signaling & behavior》2008,3(10):819-820
The cellular and molecular adaptations of non-model woody species to environmental changes are still poorly understood. We have cloned and characterised a novel non-symbiotic hemoglobin from oak roots (QpHb1) which exhibits a specific cellular distribution in the root. The QpHb1 gene is strongly expressed in the protoderm and the protoxylem cells in two Quercus species (Q. petraea and Q. robur) with contrasting adaptive potential to drought and flooding. The constitutive expression of QpHb1 in both oak species in specific root tissues combined with the reported presence of nitric oxide in the same tissues and its potential for protein S-nitrosylation could support a role for non-symbiotic hemoglobins in signalling changes in the root environment and/or in controlling some aspects of root development.Key words: nonsymbiotic haemoglobin, oak (Quercus), in situ hybridization, signalling, xylem, root, nitric oxide 相似文献
106.
Jae-Yul Cha Sangjo Han Hee-Jeon Hong Hyunji Cho Daran Kim Youngho Kwon Soon-Kyeong Kwon Max Crüsemann Yong Bok Lee Jihyun F Kim Guri Giaever Corey Nislow Bradley S Moore Linda S Thomashow David M Weller Youn-Sig Kwak 《The ISME journal》2016,10(1):119-129
Crops lack genetic resistance to most necrotrophic pathogens. To compensate for this disadvantage, plants recruit antagonistic members of the soil microbiome to defend their roots against pathogens and other pests. The best examples of this microbially based defense of roots are observed in disease-suppressive soils in which suppressiveness is induced by continuously growing crops that are susceptible to a pathogen, but the molecular basis of most is poorly understood. Here we report the microbial characterization of a Korean soil with specific suppressiveness to Fusarium wilt of strawberry. In this soil, an attack on strawberry roots by Fusarium oxysporum results in a response by microbial defenders, of which members of the Actinobacteria appear to have a key role. We also identify Streptomyces genes responsible for the ribosomal synthesis of a novel heat-stable antifungal thiopeptide antibiotic inhibitory to F. oxysporum and the antibiotic''s mode of action against fungal cell wall biosynthesis. Both classical- and community-oriented approaches were required to dissect this suppressive soil from the field to the molecular level, and the results highlight the role of natural antibiotics as weapons in the microbial warfare in the rhizosphere that is integral to plant health, vigor and development. 相似文献
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108.
Temporal variability of Black Band Disease (BBD) prevalence, incidence, recurrence, recovery and virulence was estimated in
a Diploria strigosa population from an upwelling zone of Venezuela, for 1 year between August 2004 and August 2005. The sampling spanned both
upwelling and non-upwelling seasons, and included three samplings, roughly 60 days apart, within each season. The negative
effects of BBD epizootiology in the sampling population (El Mercado reef) were positively correlated with sea surface temperature
(taken as an upwelling estimator). Disease prevalence, incidence and recurrence decreased significantly during upwelling,
and the recovery rate increased. Contrary to expectations, tissue mortality did not decrease significantly during the upwelling
season, remaining at 1.2 ± 0.7 mm day−1. BBD prevalence, and the ensuing rates of tissue mortality were higher than values previously reported for other Caribbean
reefs, even during upwelling episodes, suggesting that nutrient enrichment of the local waters by upwelling counteracts the
expected reductions of the disease prevalence and virulence due to the lower temperature. Colonies which had previously been
infected with BBD were up to six times more susceptible to new infections than those which were not infected during the preceding
7 months, suggesting that the infected colonies never healed completely. The high variability between tissue mortality values
among coral colonies also suggests that overall host health-status may alter susceptibility to BBD infections. 相似文献
109.
110.
Eight new gene assignments were demonstrated in the baboon (Papio papio, PPA) by cosegregation analysis of twelve hybrid clones obtained by fusion between PPA fibroblasts and a mouse cell line deficient in thymidine kinase. The following markers and syntenic groups were assigned: SOD1 to PPA3, GLO-ME1 to PPA-4, PGM2 to PPA5, CKBB-SORD to PPA7, LDHB to PPA11 and LDHA to PPA14. These localizations are in agreement wit hthe following homoeologies with the human karyotype: PPA3-HSA21, PPA4-HSA6, PPA5-HSA4, PPA7-HSA14 and 15, PPA11-HSA12, PPA14-HSA11. 相似文献