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101.
102.
Cyclic Purine Mononucleotides: Induction of Gibberellin Biosynthesis in Barley Endosperm 总被引:1,自引:0,他引:1
The de novo synthesis of α-amylase in barley endosperm and isolated aleurone layers is induced by 3′,5′-cyclic purine mononucleotides and gibberellic acid. The induction of α-amylase by cyclic purine mononucleotides is prevented by 2,4-DNP, inhibitors of RNA and protein syntheses, CCC, AMO-1618 and phosfon. The induction of α-amylase formation by 3′,5′-cyclic purine mononucleotides, but not by gibberellic acid, is also blocked by inhibitors of DNA synthesis. Extracts from cyclic AMP-treated endosperm halves exhibit a characteristic gibberellin-like activity which is detectable within 12 hours from the addition of the cyclic AMP. On paper chromatograms this gibberellin-like activity is located at the Rf typical for GA3. Its formation is prevented by inhibitors of DNA synthesis, CCC and AMO-1618. Glucose inhibits the formation of α-amylase induced by gibberellic acid. Glucose has no effect on the cAMP-induced gibberellin biosynthesis. The evidence shows that the cyclic purine mononucleotides induce DNA synthesis, which results in gibberellin biosynthesis, which in turn activates the synthesis of α-amylase. 相似文献
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JAY R. KAPLAN 《American anthropologist》2006,108(3):572-573
Kinship and Behavior in Primates. Bernard Chapais and Carol M. Berman, eds. Oxford University Press, 2004. 507 pp. 相似文献
106.
J. D. LOZIER N. J. MILLS P. J. PALSB
LL G. K. RODERICK 《Molecular ecology resources》2005,5(3):499-501
Hyalopterus pruni is an invasive aphid pest in California. To study the population biology of this pest both in California and its native Mediterranean region, we have developed 11 di‐ and tri‐nucleotide repeat microsatellite markers. Each locus amplified in individuals representing the full range of geographical regions and host plants where Hyalopterus is found. Polymorphism was high, ranging from six to 22 alleles per locus in the individuals screened. These loci represent the first microsatellites developed for Hyalopterus and they should be of great value in studying the invasion biology and population structure of this insect pest. 相似文献
107.
Hari D Upadhyaya Sangam L Dwivedi Michael Baum Rajeev K Varshney Sripada M Udupa Cholenahalli LL Gowda David Hoisington Sube Singh 《BMC plant biology》2008,8(1):106
Background
Plant genetic resources (PGR) are the basic raw materials for future genetic progress and an insurance against unforeseen threats to agricultural production. An extensive characterization of PGR provides an opportunity to dissect structure, mine allelic variations, and identify diverse accessions for crop improvement. The Generation Challenge Program conceptualized the development of "composite collections" and extraction of "reference sets" from these for more efficient tapping of global crop-related genetic resources. In this study, we report the genetic structure, diversity and allelic richness in a composite collection of chickpea using SSR markers, and formation of a reference set of 300 accessions. 相似文献108.
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The apparent photosynthetic affinity-for inorganic carbon inSpirulina is severely reduced by exposing the cells to CO2-depletedconditions in the light. The extent of reduction depends onthe length of exposure, the light intensity, and the O2 concentration.The photosynthetic dependence on inorganic carbon (CInorg) concentration,however, is similar at 3% O2 and at 25% O2 but in the presenceof catalase. The amount of O2 released following the additionof catalase to the cell suspension also depends on the O2 andCO2 concentrations. The addition of H2O2 either to the cellsuspension or by a treatment with methyl viologen caused a severeinhibition of the capability of the cells to accumulate inorganiccarbon internally. It is suggested that the reduction of thephotosynthetic apparent affinity to CInorg upon subjecting thecells to photoinhibitory conditions is caused by an alterationof their ability to accumulate CInorg due to the accumulationof H2O2. 相似文献