Search results for "HuR"
showing 10 items of 938 documents
Common receptor for Bacillus thuringiensis toxins Cry1Ac, Cry1Fa, and Cry1Ja in Helicoverpa armigera, Helicoverpa zea and Spodoptera exigua
2005
ABSTRACT Binding studies using 125 I-Cry1Ac and biotinylated Cry1Fa toxins indicate the occurrence of a common receptor for Cry1Ac, Cry1Fa, and Cry1Ja in Helicoverpa armigera , Helicoverpa zea , and Spodoptera exigua . Our results, along with previous binding data and the observed cases of cross-resistance, suggest that this pattern seems to be widespread among lepidopteran species.
Shared Binding Sites in Lepidoptera for Bacillus thuringiensis Cry1Ja and Cry1A Toxins
2001
ABSTRACT Bacillus thuringiensis toxins act by binding to specific target sites in the insect midgut epithelial membrane. The best-known mechanism of resistance to B. thuringiensis toxins is reduced binding to target sites. Because alteration of a binding site shared by several toxins may cause resistance to all of them, knowledge of which toxins share binding sites is useful for predicting cross-resistance. Conversely, cross-resistance among toxins suggests that the toxins share a binding site. At least two strains of diamondback moth ( Plutella xylostella ) with resistance to Cry1A toxins and reduced binding of Cry1A toxins have strong cross-resistance to Cry1Ja. Thus, we hypothesized that…
Variation in Susceptibility to Bacillus thuringiensis Toxins among Unselected Strains of Plutella xylostella
2001
ABSTRACT So far, the only insect that has evolved resistance in the field to Bacillus thuringiensis toxins is the diamondback moth ( Plutella xylostella ). Documentation and analysis of resistant strains rely on comparisons with laboratory strains that have not been exposed to B. thuringiensis toxins. Previously published reports show considerable variation among laboratories in responses of unselected laboratory strains to B. thuringiensis toxins. Because different laboratories have used different unselected strains, such variation could be caused by differences in bioassay methods among laboratories, genetic differences among unselected strains, or both. Here we tested three unselected st…
Interaction of Bacillus thuringiensis Toxins with Larval Midgut Binding Sites of Helicoverpa armigera (Lepidoptera: Noctuidae)
2004
ABSTRACT In 1996, Bt-cotton (cotton expressing a Bacillus thuringiensis toxin gene) expressing the Cry1Ac protein was commercially introduced to control cotton pests. A threat to this first generation of transgenic cotton is the evolution of resistance by the insects. Second-generation Bt-cotton has been developed with either new B. thuringiensis genes or with a combination of cry genes. However, one requirement for the “stacked” gene strategy to work is that the stacked toxins bind to different binding sites. In the present study, the binding of 125 I-labeled Cry1Ab protein ( 125 I-Cry1Ab) and 125 I-Cry1Ac to brush border membrane vesicles (BBMV) of Helicoverpa armigera was analyzed in com…
High Genetic Variability for Resistance to Bacillus thuringiensis Toxins in a Single Population of Diamondback Moth
2001
ABSTRACT The long-term benefit of insecticidal products based on Cry toxins, either in sprays or as transgenic crops, is threatened by the development of resistance by target pests. The models used to predict evolution of resistance to Cry toxins most often are monogenic models in which two alleles are used. Moreover, the high-dose/refuge strategy recommended for implementation with transgenic crops relies on the assumption that the resistance allele is recessive. Using selection experiments, we demonstrated the occurrence in a laboratory colony of diamondback moth of two different genes (either allelic or nonallelic) that confer resistance to Cry1Ab. At the concentration tested, resistance…
Global variation in the genetic and biochemical basis of diamondback moth resistance to Bacillus thuringiensis
1997
Insecticidal proteins from the soil bacterium Bacillus thuringiensis (Bt) are becoming a cornerstone of ecologically sound pest management. However, if pests quickly adapt, the benefits of environmentally benign Bt toxins in sprays and genetically engineered crops will be short-lived. The diamondback moth ( Plutella xylostella ) is the first insect to evolve resistance to Bt in open-field populations. Here we report that populations from Hawaii and Pennsylvania share a genetic locus at which a recessive mutation associated with reduced toxin binding confers extremely high resistance to four Bt toxins. In contrast, resistance in a population from the Philippines shows multilocus control, a …
Genetic and Biochemical Approach for Characterization of Resistance to Bacillus thuringiensis Toxin Cry1Ac in a Field Population of the Diamondback M…
2000
ABSTRACT Four subpopulations of a Plutella xylostella (L.) strain from Malaysia (F 4 to F 8 ) were selected with Bacillus thuringiensis subsp. kurstaki HD-1, Bacillus thuringiensis subsp. aizawai , Cry1Ab, and Cry1Ac, respectively, while a fifth subpopulation was left as unselected (UNSEL-MEL). Bioassays at F 9 found that selection with Cry1Ac, Cry1Ab, B. thuringiensis subsp. kurstaki , and B. thuringiensis subsp. aizawai gave resistance ratios of >95, 10, 7, and 3, respectively, compared with UNSEL-MEL (>10,500, 500, >100, and 26, respectively, compared with a susceptible population, ROTH). Resistance to Cry1Ac, Cry1Ab, B. thuringiensis subsp. kurstaki , and B. thuringiensis subsp…
„Na Ukrainie za owych dobrych czasów” – „Przed laty. Powieść ukraińska” Paulina Święcickiego
2020
The forgotten work and life of Paulin Święcicki (1841–1876), a writer from Kiev region and active in Galicia, represents a rare, authentic example of Polish‑Ukrainian cultural border. His debut work entitled 'Przed laty. Powieść ukraińska' (1865), despite being an artistic failure, is an interesting link between the heritage of the Romantic 'Ukrainian School' and the historical vision of Polish Borderlands in With fire and sword by Henryk Sienkiewicz. The creation of the 17th‑century reality of Ukrainian grasslands (noble, rural and Cossack existence), battle scenes (fights against the Tatars), romantic‑melodramatic plot – these are all adapted to a unique Ukrainian (not Polish‑centred) per…
Dimensions of Mystical Anthropology of the XX Century: Hesychasm and Tibetan Buddhism Compared
2009
Pētījums ir veltīts komparatīvajai reliģiski-filozofisko ideju problemātikai un mēģinājumam saskatīt saikni starp idejām un to arhetipiski empīrisko zemtekstu. Lai salīdzinātu Tibetas budisma un hesihasma antropoloģiskās idejas un to soterioloģiski empīriskās konsekvences, ir izmantota M. Eliades fenomenoloģiskā metode. Izņemot arhetipiskā kopsaucēja meklējumus, darbā ir analizētas divu tradīciju atšķirības ar A. Pjerisa izstrādātās reliģiju klasifikācijas palīdzību. Saskaņā ar to budismu varētu kvalificēt kā gnostisko, bet kristietību – kā agapeisko reliģiski-filozofisko ideju kopu. Darbs sastāv no četrām daļām. Pirmajā ir iztirzāts reliģijas būtības jautājums, meklēta atbilstoša pieeja un…
Онтологическая трансформация человека в богословии Игнатия Брянчанинова: критическое осмысление
2009
Grieķu tēvu-askētu (hesihastu) garīgās pārtapšanas (ontoloģiskās transformācijas) doktrīna, prakse un galvenās problēmas tiek pētītas uz krievu askētisma klasiķa Ignatija Brjančaņinova teoloģijas piemēra. Brjančaņinovs interpretē hesihastisko askētismu visplašākajā nozīmē – kā universāli-kristīgu garīgumu par exellence. Tāpēc Brjančaņinova personā mums ir darīšana ar specifiska ekskluzīvas domāšanas fenomena un ar īpaši ekskluzīvas hesihasma skolas rašanos krievu askētiskās tradīcijas un KPB ietvaros, kurai ir būtiska loma pareizticīgo apziņas formēšanā līdz pat mūsdienām. Brjančaņinova ontoloģiskās transformācijas doktrīna tiek sistemātiski apzināta savā saturiskajā izpausmē un kritiski iz…