Abstract:
:The conserved two-component regulatory system GacS/GacA determines the expression of extracellular products and virulence factors in a variety of Gram-negative bacteria. In the biocontrol strain CHA0 of Pseudomonas fluorescens, the response regulator GacA is essential for the synthesis of extracellular protease (AprA) and secondary metabolites including hydrogen cyanide. GacA was found to exert its control on the hydrogen cyanide biosynthetic genes (hcnABC) and on the aprA gene indirectly via a posttranscriptional mechanism. Expression of a translational hcnA'-'lacZ fusion was GacA-dependent whereas a transcriptional hcnA-lacZ fusion was not. A distinct recognition site overlapping with the ribosome binding site appears to be primordial for GacA-steered regulation. GacA-dependence could be conferred to the Escherichia coli lacZ mRNA by a 3-bp substitution in the ribosome binding site. The gene coding for the global translational repressor RsmA of P. fluorescens was cloned. RsmA overexpression mimicked partial loss of GacA function and involved the same recognition site, suggesting that RsmA is a downstream regulatory element of the GacA control cascade. Mutational inactivation of the chromosomal rsmA gene partially suppressed a gacS defect. Thus, a central, GacA-dependent switch from primary to secondary metabolism may operate at the level of translation.
journal_name
Proc Natl Acad Sci U S Aauthors
Blumer C,Heeb S,Pessi G,Haas Ddoi
10.1073/pnas.96.24.14073keywords:
subject
Has Abstractpub_date
1999-11-23 00:00:00pages
14073-8issue
24eissn
0027-8424issn
1091-6490journal_volume
96pub_type
杂志文章abstract::Diarthrodial joints are essential for load bearing and locomotion. Physiologically, articular cartilage sustains millions of cycles of mechanical loading. Chondrocytes, the cells in cartilage, regulate their metabolic activities in response to mechanical loading. Pathological mechanical stress can lead to maladaptive ...
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.1414298111
更新日期:2014-11-25 00:00:00
abstract::Comparison of about 50 pairs of homologous nucleotide sequences for different genes revealed that the substitutions between synonymous codons occurred at much higher rates than did amino acid substitutions. Furthermore, five pairs of mRNA sequences for different genes were compared in species that had diverged at the ...
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.77.12.7328
更新日期:1980-12-01 00:00:00
abstract::Hebb proposed that neuronal cell assemblies are critical for effective perception, cognition, and action. However, evidence for brain mechanisms that coordinate multiple coactive assemblies remains lacking. Neuronal oscillations have been suggested as one possible mechanism for cell assembly coordination. Prior studie...
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.1008306107
更新日期:2010-10-05 00:00:00
abstract::An explosion of new information linking activation of cell surface signal initiators to changes in gene expression has recently emerged. The focus of much of this information has centered around the agonist-dependent activation of the mitogen-activated protein (MAP) kinases. Although this intracellular signal transduc...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.90.13.5889
更新日期:1993-07-01 00:00:00
abstract::A remarkable property of Ca2+ fluxes through the inositol 1,4,5-trisphosphate (InsP3)-gated Ca2+ channel is that successive increments of InsP3 induce repeated transient release of accumulated Ca2+. The initial aim of this study was to propose a model, based on hypotheses compatible with the current description of thi...
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.91.21.10074
更新日期:1994-10-11 00:00:00
abstract::mRNA coding for mouse major transplantation antigens of the d haplotype was partially purified, copied into double-stranded cDNA, and cloned in Escherichia coli. Clones were selected by their ability to hybridize specifically with mRNA coding for H-2K, D, or L antigens. One of these clones, pH-2d-1, carries a 1200-bas...
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.78.5.2772
更新日期:1981-05-01 00:00:00
abstract::Accurate calculations of force generated and of ATP flux, in steady isotonic contractions, are made on a simple, two-state muscle model of the sliding filament type. The objective is to illustrate the proper formulation and use of a complete and self-consistent molecular model of muscle. Otherwise, the model is not me...
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.71.5.1982
更新日期:1974-05-01 00:00:00
abstract::The mechanism of the proline-catalyzed aldol reaction has stimulated considerable debate, and despite limited experimental data, at least five different mechanisms have been proposed. Complementary to recent theoretical studies we have initiated an experimental program with the goal of clarifying some of the basic mec...
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.0307979101
更新日期:2004-04-20 00:00:00
abstract::Specific binding properties of the tritium-labeled delta opiate receptor agonist [3H][2-D-penicillamine, 5-D-penicillamine]enkephalin [( 3H][D-Pen2, D-Pen5]enkephalin) were characterized in the rat brain and in a mouse neuroblastoma-rat glioma hybrid cell line (NG 108-15). Saturation isotherms of [3H][D-Pen2, D-Pen5]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.82.8.2543
更新日期:1985-04-01 00:00:00
abstract::Leptin is a pivotal regulator of energy and glucose homeostasis, and defects in leptin signaling result in obesity and diabetes. The ATP-sensitive potassium (K(ATP)) channels couple glucose metabolism to insulin secretion in pancreatic β-cells. In this study, we provide evidence that leptin modulates pancreatic β-cell...
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.1216351110
更新日期:2013-07-30 00:00:00
abstract::Transporters in the Golgi apparatus membrane translocate nucleotide sugars from the cytosol into the Golgi lumen before these can be substrates for the glycosylation of proteins, lipids, and proteoglycans. We have cloned the mammalian Golgi membrane transporter for uridine diphosphate-N-acetylglucosamine by phenotypic...
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.95.14.7888
更新日期:1998-07-07 00:00:00
abstract::The development of osteoclastic cell lines would greatly facilitate analysis of the cellular and molecular biology of bone resorption. Several cell lines have previously been reported to be capable of osteoclastic differentiation. However, such cell lines form at best only occasional excavations, suggesting that osteo...
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.90.12.5578
更新日期:1993-06-15 00:00:00
abstract::Anti-immunoglobulin treatment of fura-2-loaded Daudi cells induces a calcium mobilization as judged by the increase in the fluorescence of the dye fura-2, AM. No calcium mobilization by N-fMet-Leu-Phe is observed in these cells. However, exposure of the cells to N-fMet-Leu-Phe after the first hit with anti-immunoglobu...
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.85.23.9204
更新日期:1988-12-01 00:00:00
abstract::Knowledge of the mechanisms by which a cell detects exogenous DNA is important for controlling pathogen infection, because most pathogens entail the presence of exogenous DNA in the cytosol, as well as for understanding the cell's response to artificially transfected DNA. The cellular response to pathogen invasion has...
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.1501235112
更新日期:2015-06-02 00:00:00
abstract::Rod-shaped "ghosts" that are free of murein have been isolated from E. coli. The shape of these "ghosts" is maintained by a unit membrane soluble in sodium dodecyl sulfate. Ghosts consist of about 20-30% phospholipid (almost exclusively phosphatidylethanolamine) and 50-60% protein; a large fraction of the remaining ma...
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.70.7.2033
更新日期:1973-07-01 00:00:00
abstract::P elements have been cloned and sequenced from Drosophila nebulosa. Their sequences have diverged less than 6% from P elements of Drosophila melanogaster. However D. nebulosa P elements have nucleotide changes that close all four open reading frames found in the D. melanogaster P element. Microinjection experiments sh...
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.84.18.6491
更新日期:1987-09-01 00:00:00
abstract::If they are able to spread in wild populations, CRISPR-based gene-drive elements would provide new ways to address ecological problems by altering the traits of wild organisms, but the potential for uncontrolled spread tremendously complicates ethical development and use. Here, we detail a self-exhausting form of CRIS...
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.1716358116
更新日期:2019-04-23 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
pub_type: 杂志文章
doi:10.1073/pnas.86.4.1333
更新日期:1989-02-01 00:00:00
abstract::Abnormal tubulofilamentous structures have been identified in electron micrographs of thin sections and negatively stained impression grids prepared from brains of animals with scrapie and other spongiform encephalopathies, and we showed that such tubules contain a core of filamentous structures resembling scrapie-ass...
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.85.10.3575
更新日期:1988-05-01 00:00:00
abstract::Scores of homeobox gene-encoded transcription factors are expressed in a definite spatiotemporal pattern during embryogenesis and regulate a series of as yet unidentified target genes to help coordinate the morphogenetic process. We have suggested that homeobox gene products modulate the expression of adhesion molecul...
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.90.14.6557
更新日期:1993-07-15 00:00:00
abstract::Annealed metals are surprisingly difficult to cut, involving high forces and an unusually thick "chip." This anomaly has long been explained, based on ex situ observations, using a model of smooth plastic flow with uniform shear to describe material removal by chip formation. Here we show that this phenomenon is actua...
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.1509165112
更新日期:2015-08-11 00:00:00
abstract::Integration sites for many retrotransposons and retroviruses are determined by interactions between retroelement-encoded integrases and specific DNA-bound proteins. The Saccharomyces retrotransposon Ty5 preferentially integrates into heterochromatin because of interactions between Ty5 integrase and the heterochromatin...
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.1103665108
更新日期:2011-12-20 00:00:00
abstract::The simple yet powerful technique of induced pluripotency may eventually supply a wide range of differentiated cells for cell therapy and drug development. However, making the appropriate cells via induced pluripotent stem cells (iPSCs) requires reprogramming of somatic cells and subsequent redifferentiation. Given ho...
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.1103113108
更新日期:2011-05-10 00:00:00
abstract::Productive T cell recognition of antigen-presenting cells (APCs) is normally accompanied by the formation of a cell-cell contact called the "immunological synapse." Our understanding of the steps leading up to this formation has been limited by the absence of tools for analyzing 3D surfaces and surface distributions a...
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.192573999
更新日期:2002-11-12 00:00:00
abstract::This work explores the concept that differential wave function overlap between excited states can be engineered within a molecular chromophore. The aim is to control excited state wave function symmetries, so that symmetry matches or mismatches result in differential orbital overlap and define low-energy trajectories ...
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.2018521118
更新日期:2021-01-26 00:00:00
abstract::Transport affects climate directly and indirectly through mechanisms that cause both warming and cooling of climate, and the effects operate on very different timescales. We calculate climate responses in terms of global mean temperature and find large differences between the transport sectors with respect to the size...
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.0804844105
更新日期:2008-12-09 00:00:00
abstract::Echoviruses are enteroviruses that belong to Picornaviridae. Many echoviruses use decay-accelerating factor (DAF) as their cellular receptor. DAF is a glycosylphosphatidyl inositol-anchored complement regulatory protein found on most cell surfaces. It functions to protect cells from complement attack. The cryo-electro...
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.152161599
更新日期:2002-08-06 00:00:00
abstract::The nonreceptor tyrosine phosphatase Shp2 (PTPN11) has been implicated in tyrosine kinase, cytokine, and integrin receptor signaling. We show here that conditional mutation of Shp2 in neural crest cells and in myelinating Schwann cells resulted in deficits in glial development that are remarkably similar to those obse...
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.0904336106
更新日期:2009-09-29 00:00:00
abstract::Diabetes mellitus is characterized by either the inability to produce insulin (type 1 diabetes) or as insensitivity to insulin secreted by the body (type 2 diabetes). In either case, the body is unable to move blood glucose efficiently across cell membranes to be used. This leads to a variety of local and systemic det...
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.1007884107
更新日期:2010-07-27 00:00:00
abstract::The assembly and composition of human excision nuclease were investigated by electrophoretic mobility shift assay and DNase I footprinting. Individual repair factors or any combination of up to four repair factors failed to form DNA-protein complexes of high specificity and stability. A stable complex of high specific...
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.95.12.6669
更新日期:1998-06-09 00:00:00