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71.
The application of ethephon to a single leaf of Cucurbita pepo L. cv. Trailing Marrow plants caused a huge increase in ethylene production from the treated organ and an increased rate of ethylene production from other parts of the plant. These increases were particularly marked in the shoot apex and expanding leaf. Prior treatment with aminoethoxyvinylglycine (AVG), an ethylene biosynthesis inhibitor, blocked the increased production of ethylene at sites distant from the point of ethephon application. This strongly suggests that the increased ethylene production at these distant sites is due to ethylene biosynthesis and not a result of the translocation of ethylene released by the breakdown of ethephon at the site of application. Assays of 1-aminocyclopropane-l-carboxylic acid (ACC), an ethylene precursor, showed that it increased substantially after ethephon application but was at undetectable levels in the presence of AVG. It is proposed that the application of ethephon stimulates ethylene biosynthesis, but that transport through the plants is effected by ACC which is then converted to ethylene at the shoot apex and leaves. 相似文献
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The complete nucleotide sequence of the I-E alpha d immune response gene. 总被引:12,自引:4,他引:8 下载免费PDF全文
J J Hyldig-Nielsen L Schenning U Hammerling E Widmark E Heldin P Lind B Servenius T Lund R Flavell J S Lee J Trowsdale P H Schreier F Zablitzky D Larhammar P A Peterson L Rask 《Nucleic acids research》1983,11(15):5055-5071
We have isolated and sequenced the complete murine I-E alpha immune response gene of the H-2db haplotype. The I-E alpha d gene consists of 5300 basepairs and is organized into five or possibly six exons that correspond to different domains of the alpha chain. The amino acid sequence deduced from the I-E alpha gene shows 75% homology to its human counterpart, the HLA-DR alpha chain. The absence of I-E antigen in H-2 mice is due to lack of E alpha chain synthesis. We show here that this defect is caused by a deletion in the 5' end of the I-E alpha b gene. 相似文献
74.
Use of a New Buffer System with Formalinized Sheep Erythrocytes in the Rubella Hemagglutination-Inhibition Test 总被引:4,自引:1,他引:3 下载免费PDF全文
The increased sensitivity and improved agglutination and settling patterns of formalinized sheep erythrocytes in a new buffer, HEPES (N-2-hydroxyethylpiperazine N'-2'-ethanesulfonic acid), make this system more suitable for use in the rubella hemagglutination-inhibition test. 相似文献
75.
D F Steiner S Cho P E Oyer S Terris J D Peterson A H Rubenstein 《The Journal of biological chemistry》1971,246(5):1365-1374
76.
Escherichia coli and Bacillus megaterium rendered permeable to ribonucleoside triphosphates by toluene treatment retain the capacity to synthesize discrete ribonucleic acid species. 相似文献
77.
Proteolytic processing in the biosynthesis of insulin and other proteins 总被引:41,自引:0,他引:41
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Purification of myeloperoxidases from the bone marrow of the guinea pig 总被引:22,自引:0,他引:22