Abstract:
:Phylogenetic comparison of rRNA sequences has suggested that a pseudoknot structure exists in the central domain of small-subunit rRNA. In Escherichia coli 16S rRNA, this pseudoknot would form when positions 570 and 571 pair with positions 865 and 866. Mutations were introduced into this pseudoknot at the phylogenetically invariant nucleotides U571 and A865. Single mutations of U to A at 571 or A to U at 865 dramatically altered the structural stability of the 30S subunit and also impaired the function of the subunit in translation. When the mutations were combined to create a compensatory pairing, the normal structure of the 30S subunit was restored, and the function of the mutant subunit in translation returned to wild-type levels. These results demonstrate the existence of a higher order structure in rRNA that directly affects the folding of the 30S subunit. Given the position of this structure in the three-dimensional model of the small subunit and the additional interactions that are likely to form in the same rRNA region, the central domain pseudoknot appears to contribute to a complex structure of rRNA that controls the conformational state of the ribosome.
journal_name
Proc Natl Acad Sci U S Aauthors
Vila A,Viril-Farley J,Tapprich WEdoi
10.1073/pnas.91.23.11148subject
Has Abstractpub_date
1994-11-08 00:00:00pages
11148-52issue
23eissn
0027-8424issn
1091-6490journal_volume
91pub_type
杂志文章abstract::Many thylakoid lumen proteins are synthesized outside the chloroplast as larger molecular weight precursors and then processed to their mature size during transport to the lumenal space. We have examined the post-translational processing of thylakoid lumen proteins in vivo by pulse-radiolabeling experiments with Chlam...
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.90.5.1862
更新日期:1993-03-01 00:00:00
abstract::The autoimmune dermatologic disease pemphigus vulgaris (PV) is associated with the HLA serotypes DR4 and DRw6. Susceptibility to PV could be conferred either by sequences shared between the DR4 and DRw6 haplotypes or by different sequences in these haplotypes. We have examined the distribution of DR and DQ beta-chain ...
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.85.10.3504
更新日期:1988-05-01 00:00:00
abstract::Although infection by primary HIV type 1 (HIV-1) isolates normally requires the functional interaction of the viral envelope protein with both CD4 and the CCR-5 coreceptor, a subset of such isolates also are able to use the distinct CCR-3 receptor. By analyzing the ability of a series of wild-type and chimeric HIV-1 e...
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.95.13.7682
更新日期:1998-06-23 00:00:00
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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
doi:10.1073/pnas.96.11.6517
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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
doi:10.1073/pnas.0902688106
更新日期:2009-05-12 00:00:00
abstract::Specific Ca2+ binding and Ca2+ activation of ATPase activity in scallop myosin require a regulatory light chain (RLC) from regulated (molluscan or vertebrate smooth) myosin; hybrids containing vertebrate skeletal RLCs do not bind Ca2+ and their ATPase activity is inhibited. Chimeras between scallop and chicken skeleta...
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.91.19.8762
更新日期:1994-09-13 00:00:00
abstract::CD28 is a 44-kDa glycoprotein expressed as a homodimer on the surface of a major subset of human T cells. Previous studies have demonstrated that the binding of monoclonal antibodies to the CD28 surface antigen can augment the proliferation of purified human T cells stimulated with suboptimal doses of mitogens or anti...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.86.4.1333
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abstract::Let t --> gamma(t), 0 = t = 1, be a smooth curve in IR(n). Define the maximal function [unk](f) by [unk](f)(x) = sup(0 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.73.12.4295 更新日期:1976-12-01 00:00:00
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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
doi:10.1073/pnas.97.25.13961
更新日期:2000-12-05 00:00:00
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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
doi:10.1073/pnas.78.1.611
更新日期:1981-01-01 00:00:00
abstract::To achieve accurate aminoacylation of tRNAs with their cognate amino acids, errors in aminoacylation are corrected by the "editing" mechanism in several aminoacyl-tRNA synthetases. Phenylalanyl-tRNA synthetase (PheRS) hydrolyzes, or edits, misformed tyrosyl-tRNA with its editing domain in the beta subunit. We report t...
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.0603182103
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abstract::Renal cells isolated from vitamin D-deficient chicks had an increased Na+-dependent phosphate uptake when preincubated with 1,25-dihydroxycholecalciferol [1,25-(OH)2D3]. Phosphate uptake in the absence of Na+ and methyl alpha-glucoside uptake dependent on Na+ were not affected. Phosphate uptake was stimulated 15% by 0...
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.79.11.3532
更新日期:1982-06-01 00:00:00
abstract::An obstacle in the utilization of catalytic Abs for selective prodrug activation in cancer therapy has been systemic tumor targeting. Here we report the generation of catalytic Abs that effectively target tumor cells with undiminished prodrug activation capability. Ab conjugates were prepared by covalent conjugation o...
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.0700223104
更新日期:2007-03-27 00:00:00
abstract::DNA heteroduplexes with single unpaired bases of the four different kinds were prepared by annealing separated strands of bacteriophage lambda DNA and used to transfect Escherichia coli. Genetic analysis of the progeny phages obtained from transfected bacteria indicates that the E. coli mismatch repair system can reco...
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.83.10.3395
更新日期:1986-05-01 00:00:00
abstract::Tissue kallikrein (TK) is a serine protease synthetized in renal tubular cells located upstream from the collecting duct where renal potassium balance is regulated. Because secretion of TK is promoted by K+ intake, we hypothesized that this enzyme might regulate plasma K+ concentration ([K+]). We showed in wild-type m...
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:2010-07-27 00:00:00
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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
doi:10.1073/pnas.84.14.4811
更新日期:1987-07-01 00:00:00
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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
doi:10.1073/pnas.0500187102
更新日期:2005-02-22 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:2017-08-01 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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doi:10.1073/pnas.88.23.10465
更新日期:1991-12-01 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:1988-09-01 00:00:00
abstract::Treatment of Madin-Darby bovine kidney (MDBK) cells with human interferon (IFN)-alpha 2 at 37 degrees C results in a dose-dependent inhibition of cell growth and a reduction of the subsequent binding of 125I-labeled epidermal growth factor (EGF) at 4 degrees C. Human IFN-beta and -gamma, which exhibit little antiviral...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1986-11-01 00:00:00
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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:2021-02-09 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
doi:10.1073/pnas.89.16.7496
更新日期:1992-08-15 00:00:00
abstract::Intrinsic genetic instability of RNA viruses may lead to the accumulation of revertants during manufacture of live viral vaccines, requiring rigorous quality control to ensure vaccine safety. Each lot of oral poliovirus vaccine (OPV) is tested for neurovirulence in animals and also for the presence of neurovirulent re...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-11-16 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:1976-03-01 00:00:00
abstract::The extracellular matrix (ECM) is an intricate network composed of an array of macromolecules capable of regulating the functional responsiveness of cells. Its composition greatly varies among different types of tissue, and dysregulation of its metabolism may contribute to vascular remodeling during the pathogenesis o...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1996-05-28 00:00:00
abstract::Global biological datasets generated by genomics, transcriptomics, and proteomics provide new approaches to understanding the relationship between the genome and the synapse. Combined transcriptome analysis and multielectrode recordings of neuronal network activity were used in mouse embryonic primary neuronal culture...
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.0609071104
更新日期:2007-03-13 00:00:00
abstract::Integrin alphanubeta3 is found on a subset of tumor blood vessels where it is associated with angiogenesis and malignant tumor growth. We designed an alphanubeta3-targeted nanoparticle (NP) encapsulating the cytotoxic drug doxorubicin (Dox) for targeted drug delivery to the alphanubeta3-expressing tumor vasculature. W...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-07-08 00:00:00
abstract::Deregulation of energy metabolism by external interventions or mutations in metabolic genes can extend lifespan in a wide range of species. We describe mutations in Drosophila melanogaster that confer resistance to oxidative stress and display a longevity phenotype. These phenotypes are associated with molecular lesio...
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:2006-01-31 00:00:00