Abstract:
:We have utilized a recombinant vector system designed to study gene control elements by fusing them to the Escherichia coli galactokinase gene (galK) to examine the effects of gene expression that result from introducing changes into the 5' noncoding leader region of the galK transcription unit. We varied the length of the 5' leader region and found no effect on galK expression, provided that the galK initiation codon remained the first AUG in the transcription unit. Using synthetic linkers, we then inserted specific sequences, each containing a single AUG codon at a defined position within the leader region. We found that the AUG inserts had widely different effects on galK expression and that the sequences surrounding the inserted AUG codons determined the magnitude of these effects. In addition, we placed these upstream inserted AUG codons into each of the three possible translation reading frames so that translation occurring in these frames terminates prior to, within, or downstream of the galK initiation codon, respectively. Single-nucleotide frameshift mutations were also introduced into one of these constructs to shift upstream translation into the other two possible reading frames. Depending upon where upstream translation stopped relative to the galK initiation codon, we observed consistently different effects on galK expression. Our results show that an upstream AUG that interferes with downstream translation initiation exerts its greatest effect when it translates out-of-frame through the downstream initiator into the gene. If translation is stopped upstream of or within the initiator, an unexpectedly high level of expression from the downstream AUG is maintained.
journal_name
Proc Natl Acad Sci U S Aauthors
Johansen H,Schümperli D,Rosenberg Mdoi
10.1073/pnas.81.24.7698subject
Has Abstractpub_date
1984-12-01 00:00:00pages
7698-702issue
24eissn
0027-8424issn
1091-6490journal_volume
81pub_type
杂志文章abstract::Cytochrome P450 enzymes are monooxygenases that contain a functional heme b group linked to a conserved cysteine with a thiolate bond. In the native state, the central iron atom is hexacoordinated with a covalently bound water molecule. The exclusion of solvent molecules from the active site is essential for efficient...
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.94.6.2133
更新日期:1997-03-18 00:00:00
abstract::Epstein-Barr nuclear antigen 1 (EBNA1) plays a vital role in the maintenance of the viral genome and is the only viral protein expressed in nearly all forms of Epstein-Barr virus (EBV) latency and EBV-associated diseases, including numerous cancer types. To our knowledge, no specific agent against EBV genes or protein...
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.1915372116
更新日期:2019-12-10 00:00:00
abstract::The replication of simian virus 40 (SV40) DNA is dependent upon a single viral protein [tumor (T) antigen] and multiple cellular proteins. To define the required cellular proteins, we have made use of a cell-free system that supports the replication of plasmid DNA molecules containing the SV40 origin of replication. W...
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.86.10.3584
更新日期:1989-05-01 00:00:00
abstract::Significantly above-chance detection of stimuli presented within the field defect of patients with postgeniculate lesions is termed "blindsight." It has been proposed that those with blindsight are more likely to benefit from visual rehabilitation by repeated stimulation, leading to increased visual sensitivity within...
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.1318395110
更新日期:2013-11-05 00:00:00
abstract::Phosphatase PP2A expression levels are positively correlated to the clinical severity of systemic lupus erythematosus (SLE) and IL17A cytokine overproduction, indicating a potential role of PP2A in controlling TH17 differentiation and inflammation. By generating a mouse strain with ablation of the catalytic subunit α ...
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.1807484116
更新日期:2019-01-15 00:00:00
abstract::The cytokine IFN-γ is a critical regulator of immune system development and function. Almost all leukocytes express the receptor for IFN-γ, yet each cell type elicits a different response to this cytokine. Cell type-specific effects of IFN-γ make it difficult to predict the outcomes of the systemic IFN-γ blockade and ...
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.1804556115
更新日期:2018-11-06 00:00:00
abstract::A ribosomal RNA-encoding DNA (rDNA) cloned sequence, consisting of a 0.8-kilobase fragment from the 26S/nontranscribed spacer region, was used to identify diagnostic restriction enzyme fragments that distinguish the Moreton and Torresian subspecies of the grasshopper Caledia captiva. These restriction fragments were 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.84.11.3946
更新日期:1987-06-01 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.1436338100
更新日期:2003-07-08 00:00:00
abstract::In the vertebrate embryo, the cephalic neural crest cells (CNCCs) produce cells belonging to two main lineages: the neural [including neurons, glial cells of the peripheral nervous system (PNS), and melanocytes] and the mesenchymal (chondrocytes, osteoblasts, smooth muscle cells, and connective tissue cells), whereas ...
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.0708806104
更新日期:2007-12-11 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:2007-07-03 00:00:00
abstract::If, because of trade-offs or similar considerations, components of fitness are negatively correlated in equilibrium populations, they may then exhibit no correlation with total fitness. Lack of correlation with fitness is a fundamental characteristic of selective neutrality. Hence, selectively important traits become ...
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.87.5.2018
更新日期:1990-03-01 00:00:00
abstract::We have studied a naturally occurring small-molecule antimitotic called diazonamide A. Diazonamide A is highly effective at blocking spindle assembly in mammalian cell culture and does so through a unique mechanism. A biotinylated form of diazonamide A affinity purifies ornithine delta-amino transferase (OAT), a mitoc...
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.0610832104
更新日期:2007-02-13 00:00:00
abstract::Protein sequences are often highly redundant and evolution can change them beyond recognition. It can therefore be difficult to identify proteins with functional or structural similarities by inspection of their sequences. Here we have used an experimental evolutionary approach to detect hidden similarities between th...
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.2134365100
更新日期:2003-11-11 00:00:00
abstract::Visual speech facilitates auditory speech perception, but the visual cues responsible for these benefits and the information they provide remain unclear. Low-level models emphasize basic temporal cues provided by mouth movements, but these impoverished signals may not fully account for the richness of auditory informa...
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:2020-07-21 00:00:00
abstract::Huntington's disease (HD) is a fatal, genetic, neurological disorder resulting from a trinucleotide repeat expansion in the gene that encodes for the protein huntingtin. These excessive repeats confer a toxic gain of function on huntingtin, which leads to the degeneration of striatal and cortical neurons and a devasta...
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.0508875103
更新日期:2006-06-13 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.1500525112
更新日期:2015-09-22 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.87.17.6502
更新日期:1990-09-01 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2013-05-14 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.96.23.13159
更新日期:1999-11-09 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:2006-09-19 00:00:00
abstract::Amyloid beta-protein (Abeta) is linked to neuronal injury and death in Alzheimer's disease (AD). Of particular relevance for elucidating the role of Abeta in AD is new evidence that oligomeric forms of Abeta are potent neurotoxins that play a major role in neurodegeneration and the strong association of the 42-residue...
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.222681699
更新日期:2003-01-07 00:00:00
abstract::T cells must respond differently to antigens of varying affinity presented at different doses. Previous attempts to map peptide MHC (pMHC) affinity onto T-cell responses have produced inconsistent patterns of responses, preventing formulations of canonical models of T-cell signaling. Here, a systematic analysis of T-c...
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.1608820113
更新日期:2016-10-25 00:00:00
abstract::During early postnatal development, sensory regions of the brain undergo periods of heightened plasticity which sculpt neural networks and lay the foundation for adult sensory perception. Such critical periods were also postulated for learning and memory but remain elusive and poorly understood. Here, we present evide...
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.1810125115
更新日期:2018-12-04 00:00:00
abstract::Cytochrome c oxidase (CcO) uses the energy released by reduction of O2 to H2O to drive eight charges from the high pH to low pH side of the membrane, increasing the electrochemical gradient. Four electrons and protons are used for chemistry, while four more protons are pumped. Proton pumping requires that residues on ...
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.1407187111
更新日期:2014-08-26 00:00:00
abstract::Transforming growth factor beta (TGF-beta) signals through a receptor complex containing the type I (TGF-beta RI) and type II (TGF-beta RII) receptors. We describe here biochemical studies on early events in the TGF-beta signaling pathways. TGF-beta RII is highly phosphorylated when expressed alone in COS-1 cells; its...
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.92.5.1565
更新日期:1995-02-28 00:00:00
abstract::Treatment of C57BL/6 or NOD mice with a monoclonal antibody to the CSF-1 receptor resulted in depletion of the resident macrophages of pancreatic islets of Langerhans that lasted for several weeks. Depletion of macrophages in C57BL/6 mice did not affect multiple parameters of islet function, including glucose response...
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.1713543114
更新日期:2017-11-28 00:00:00
abstract::Worldwide, 90% of HIV-1 infections are transmitted heterosexually. Because the genital mucosa are the sites of initial contact with HIV-1 for most exposed individuals, study of the virus from the genital tract is critical for the development of vaccines and therapeutics. Previous analyses of HIV-1 in various tissues h...
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.2134064100
更新日期:2003-10-28 00:00:00
abstract::The effects of divalent ionophores (A23187 and ionomycin), Ca2+ channel agonist (BAY K 8644), and protein kinase C (C-kinase) activators [phorbol 12-myristate 13-acetate (PMA), mezerein] on bovine tracheal smooth muscle contraction were investigated. A23187 (5 microM) and ionomycin (0.5 microM) produced a prompt but 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.82.24.8835
更新日期:1985-12-01 00:00:00
abstract::We have cloned and characterized cDNAs coding for a receptor-class phosphotyrosine phosphatase gene from Drosophila melanogaster. The gene maps to the polytene chromosome bands 99A7-8. The cDNA clones code for a polypeptide of 1301 amino acids with a predicted molecular mass of 145 kDa. The extracellular domain includ...
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.88.24.11266
更新日期:1991-12-15 00:00:00