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11.
Summary The types and amount of plasma membrane proteins synthesized during cell elongation in response to auxin (2,4-dichlorophenoxyacetic acid) treatment were investigated. Auxin-treated and control soybean (Glycine max L.) hypocotyl segments were incubated with [35S]methionine for various times, ranging from 0.5 to 18 h, prior to isolation of plasma membrane by aqueous two-phase partitioning. Protein accumulated in the plasma membrane after auxin treatment. Despite this accumulation, the protein incorporation rate, estimated by the amount of label in the plasma membrane following a 0.5 h [35S]methionine pulse, was unaffected by auxin treatment at both 0.5 and 18 h of treatment. Protein apparently accumulated by a mechanism distinct from enhanced incorporation. The plasma membrane proteins synthesized by elongating segments differed from controls at 18 h, as evidenced by the pattern of fluorographs following a 0.5 h radiolabelling. However, auxin treatment did not alter the 2-D gel pattern of the polypeptides detectable by silver stain.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- IEF
isoelectric focusing
- PM
plasma membrane
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis 相似文献
12.
13.
Marta Royo Vicente Chulvi Elena Mulet Laura Ruiz-Pastor 《Journal of Industrial Ecology》2023,27(2):562-586
One of the approaches followed by the circular economy (CE) to achieve sustainability through design is product life extension. Extending the life of products to make them useful for as long as possible is a means to reduce waste production and materials consumption, as well as the related impacts. For designers, conceptualizing products in a way that allows them to be used for longer is a challenge, and assessing how well they extend their lifespan can be helpful when it comes to choosing the best proposal. In this paper, 70 tools and methods related to eco-design and circular economy are studied to determine how many of them consider parameters related to life extension and which can be applied in the early stages of design. The results of the analysis show that most of the existing tools and methods are applicable to developed products, and only a few of them take into account parameters related to extending the useful life. Of the 70 tools and methods, only 14 include some parameter related to life extension and are applicable to concepts. CE toolkit, Eco-design PILOT, CE Designer, Circularity Assessment tool, Circularity Potential Indicator and Circular Design Tools take into consideration eight or more parameters to assess life extension in concepts. This will help designers select the most appropriate and will indicate the need for more complete tools to consider useful life extension in the early stages of design and thus enhance the selection of more sustainable products. 相似文献
14.
We have studied the presence of a cloned fragment of DNA from Drosophila melanogaster in other organisms by means of nucleic acid hybridization analysis. The isolated region is localized in polytene chromosomes at the 63F subdivision. This region includes a puff that responds within minutes to ecdysone stimulation. We have found that 63F DNA from D. melanogaster hybridizes 'in situ' to both DNA and RNA from D. simulans, D. teissieri, and D. hydei. In all these species the isolated DNA remains associated with one early-ecdysone stimulated puff. The isolated Drosophila recombinant DNA is also complementary to polyadenylated RNA from foetal and adult rat liver but fails to hybridize to the nonpolyadenylated RNA classes from both sources and to polyadenylated RNA from rat mammary glands. 相似文献
15.
In extracts obtained by treating rye embryo ribosomes with 0.5 M NH4Cl, nuclease activity was noted towards double-stranded RNA from virus of Penicillium chrysogenum and towards synthetic poly (A)-poly (U) and poly (I)-poly (C) complexes. 相似文献
16.
I. Marta Evans Ronald R. D. Croy Philippa Hutchinson Donald Boulter Peter I. Payne Margaret E. Gordon 《Planta》1979,144(5):455-462
Polyribosomes which have template activity in the wheat germ system have been isolated from developing pea seeds. Some of the translation products have identical mobilities to the vicilin and legumin subunits by SDS-PAGE. Certain products were specifically immunoprecipitated with antisera prepared against purified vicilin and legumin fractions. Various RNA fractions including poly A-rich RNA have also been isolated from polyribosomes and shown to direct the synthesis of polyripeptides whose properties are similar to the storage protein subunits. The results are discussed in relationship to other investigations with seed storage protein biosynthesis in vitro.Abbreviations DTT
dithiothreitol
- SDS-PAGE
SDS-polyacrylamide gel electrophoresis
- TCA
tricarboxylic acid 相似文献
17.
Extrachromosomal DNA in Thiobacillus A2 总被引:1,自引:0,他引:1
18.
NAD-linked lactate, malate, glycerophosphate, alcohol and nonspecific dehydrogenases, aspartate aminotransferases, and soluble esterases from extracts of tissues of individuals from a wild population of Calomys musculinus (Rodentia, Cricetidae) have been analyzed by means of starch gel electrophoresis and specific staining. Allelic frequencies and heterozygosity have been determined. Mendelian inheritance of some of the variants detected was confirmed by breeding experiments. Ten out of fifteen (66.6%) of the genetic loci investigated presented polymorphism. Mean heterozygosity per locus was very high (H=0.2014, se 0.046).This work has been supported, in part, by grants from the Secretaria de Ciencia y Tecnología de la Nación (National Program for Endemic Diseases) and from the Fundación Emilio Ocampo. C. N. G. is a Fellow and A. B. a Career Investigator of the Consejo Nacional de Investigaciones Científicas y Técnicas of Argentina. 相似文献
19.
Marta L. Silva Baltazar C Nuno S. Osrio Pedro N. S. Rodrigues Ana Raquel Maceiras Margarida Saraiva 《PLoS pathogens》2022,18(5)
Tuberculosis (TB), one of the deadliest threats to human health, is mainly caused by 2 highly related and human-adapted bacteria broadly known as Mycobacterium tuberculosis and Mycobacterium africanum. Whereas M. tuberculosis is widely spread, M. africanum is restricted to West Africa, where it remains a significant cause of tuberculosis. Although several differences have been identified between these 2 pathogens, M. africanum remains a lot less studied than M. tuberculosis. Here, we discuss the genetic, phenotypic, and clinical similarities and differences between strains of M. tuberculosis and M. africanum. We also discuss our current knowledge on the immune response to M. africanum and how it possibly articulates with distinct disease progression and with the geographical restriction attributed to this pathogen. Understanding the functional impact of the diversity existing in TB-causing bacteria, as well as incorporating this diversity in TB research, will contribute to the development of better, more specific approaches to tackle TB. 相似文献
20.
Anna Junkiert-Czarnecka Maria Pilarska-Deltow Aneta Bk Marta Heise Anna Latos-Bieleska Jacek Zaremba Alicja Bartoszewska-Kubiak Olga Haus 《Current issues in molecular biology》2022,44(4):1472
Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet. 相似文献