Abstract:
:Antibodies to DNA in the left-handed (Z) conformation bind to acid-fixed polytene chromosomes of both Chironomus thummi and Drosophila melanogaster, as shown by direct and indirect immunofluorescence. Comparison of the phase-contrast, immunofluorescence, and DNA staining patterns shows a predominant localization of the antibody to the regions of high contrast and DNA density, the bands. The immunofluorescence is completely abolished by competition with polynucleotides in the Z conformation but not by those in the B form. DNase but not RNase treatment eliminates the antibody staining. Actinomycin D inhibits binding, whereas mithramycin has no effect. The highly reproducible immunofluorescence patterns obtained with the anti-Z-DNA antibodies demonstrate variations in fluorescence intensity between particular bands, which can be quantitated by laser scanning and photon counting techniques. The telomeric regions and DNA strands associated with end-to-end chromosome linkage and ectopic pairing are exceptionally bright. At saturation, average values of 1 IgG molecule per 3,000 base pairs and 1 per 15,000 base pairs are found in the intensely and weakly staining regions, respectively. An alternative statement is that the left-handed Z-DNA conformation is present at a frequency of 0.02-0.1%. The measured differences reflect variations in the local density of Z-DNA sites and not in the affinity for the specific antibody, which appears to be relatively constant throughout the chromosomes (Kd approximately equal to 10 nM). These observations taken together with results of biophysical studies on the properties of Z-DNA in solution suggest that regions of DNA in the left-handed conformation could be involved in higher-order structural organization of chromosomes and possibly in modulation of their functional state.
journal_name
Proc Natl Acad Sci U S Aauthors
Arndt-Jovin DJ,Robert-Nicoud M,Zarling DA,Greider C,Weimer E,Jovin TMdoi
10.1073/pnas.80.14.4344subject
Has Abstractpub_date
1983-07-01 00:00:00pages
4344-8issue
14eissn
0027-8424issn
1091-6490journal_volume
80pub_type
杂志文章abstract::Pith parenchyma cells store water in various plant organs. These cells are especially important for producing sugar and ethanol from the sugar juice of grass stems. In many plants, the death of pith parenchyma cells reduces their stem water content. Previous studies proposed that a hypothetical D gene might be respons...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1807501115
更新日期:2018-09-11 00:00:00
abstract::The ability of specific gangliosides to function as host cell receptors for Sendai virus was investigated by using Madin-Darby bovine kidney cells which become resistant to infection upon treatment with Vibrio cholerae sialidase. Sialidase-treated cells were incubated for 20 min at 37 degrees C with individual, highly...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.9.5406
更新日期:1981-09-01 00:00:00
abstract::We have previously shown that chronic activation of mitogenic signaling induced by over-expression of c-myc and transforming growth factor-alpha (TGFalpha) transgenes in mouse liver induces a state of oxidative stress. We therefore proposed that increased reactive oxygen species (ROS) generation might be responsible f...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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abstract::Striatal inhibition plays an important role in models of cortex-basal ganglia function and is altered in many basal ganglia diseases. The gamma-aminobutyric acid ergic spiny projection neuron comprises >95% of striatal neurons, but despite strong anatomical evidence, the electrophysiological properties and functions o...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Superoxide dismutase from chicken-liver mitochondria (manganese enzyme) and the two dismutases from Escherichia coli (manganese and iron enzymes) were analyzed through 29 cycles of automated Edman degradations. The high degree of homology among the amino-terminal sequences of these three dismutases corroborates their ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.70.12.3725
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abstract::We have characterized seven murine retinoic acid receptor gamma cDNA isoforms (mRAR-gamma 1 to -gamma 7) generated by alternative splicing of at least seven exons. These isoforms differ from one another in their 5' untranslated region and in two cases (mRAR-gamma 1 and -gamma 2) differ in their N-terminal A region, wh...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1991-04-15 00:00:00
abstract::Mutants of Arabidopsis that contain reduced levels of polyunsaturated fatty acids showed growth characteristics at 22 degrees C that were very similar to wild type. By contrast, at 12 degrees C, the mutants failed to undergo stem elongation during reproductive growth although they produced normal flowers and fertile s...
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更新日期:1993-07-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1994-09-27 00:00:00
abstract::The DNA damage response is an essential process for the survival of living cells. In a subset of stress-responsive genes in humans, Elongin controls transcription in response to multiple stimuli, such as DNA damage, oxidative stress, and heat shock. Yeast Elongin (Ela1-Elc1), along with Def1, is known to facilitate ub...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2020-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2004-10-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::A decade ago it was discovered that mature birds are able to regenerate hair cells, the receptors for auditory perception. This surprising finding generated hope in the field of auditory neuroscience that new hair cells someday may be coaxed to form in another class of warm-blooded vertebrates, mammals. We have made c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1992-06-01 00:00:00
abstract::One of the factors required for the antiviral activity of the synthetic nucleoside, ribavirin (1-beta-D-ribofuranosyl-1,2,4-triazole-3-carboxamide), is the ability of the molecule to adopt the substrate conformation specified by the enzyme for which it is a competitive inhibitor, inosine 5'-phosphate dehydrogenase (IM...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1976-12-01 00:00:00
abstract::Genomes exhibit diverse patterns of species-specific GC content, GC and AT skews, codon bias, and mutation bias. Despite intensive investigations and the rapid accumulation of sequence data, the causes of these a priori different genome biases have not been agreed on and seem multifactorial and idiosyncratic. We show ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2009-01-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2017-09-05 00:00:00