Abstract:
:Pathogenic Yersinia spp. carry a large common plasmid that encodes a number of essential virulence determinants. Included in these factors are the Yersinia-secreted proteins called Yops. We analyzed the consequences of wild-type and mutant strains of Yersinia pseudotuberculosis interactions with the macrophage cell line RAW264. 7 and murine bone marrow-derived macrophages. Wild-type Y. pseudotuberculosis kills approximately 70% of infected RAW264.7 macrophages and marrow-derived macrophages after an 8-h infection. We show that the cell death mediated by Y. pseudotuberculosis is apoptosis. Mutant Y. pseudotuberculosis that do not make any Yop proteins no longer cause host cell death. Attachment to host cells via invasin or YadA is necessary for the cell death phenotype. Several Yop mutant strains that fail to express one or more Yop proteins were engineered and then characterized for their ability to cause host cell death. A mutant with a polar insertion in YpkA Ser/Thr kinase that does not express YpkA or YopJ is no longer able to cause apoptosis. In contrast, a mutant no longer making YopE or YopH (a tyrosine phosphatase) induces apoptosis in macrophages similar to wild type. When yopJ is added in trans to the ypkAyopJ mutant, the ability of this strain to signal programmed cell death in macrophages is restored. Thus, YopJ is necessary for inducing apoptosis. The ability of Y. pseudotuberculosis to promote apoptosis of macrophages in cell culture suggests that this process is important for the establishment of infection in the host and for evasion of the host immune response.
journal_name
Proc Natl Acad Sci U S Aauthors
Monack DM,Mecsas J,Ghori N,Falkow Sdoi
10.1073/pnas.94.19.10385subject
Has Abstractpub_date
1997-09-16 00:00:00pages
10385-90issue
19eissn
0027-8424issn
1091-6490journal_volume
94pub_type
杂志文章abstract::Despite the growing interest in collective phenomena such as "swarm intelligence" and "wisdom of the crowds," little is known about the mechanisms underlying decision-making in vertebrate animal groups. How do animals use the behavior of others to make more accurate decisions, especially when it is not possible to ide...
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.0710344105
更新日期:2008-05-13 00:00:00
abstract::Translation initiation of the hepatitis C virus (HCV) RNA genome occurs through an internal ribosome entry site in a cap-independent manner. Here, we have examined the interaction between La antigen and the HCV 5' noncoding region (5'NCR). In this analysis, competitor RNAs derived from HCV 5'NCR carrying deletions 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.94.6.2249
更新日期:1997-03-18 00:00:00
abstract::The anti-inflammatory activity of intravenous Ig (IVIG) results from a minor population of the pooled IgG molecules that contains terminal alpha2,6-sialic acid linkages on their Fc-linked glycans. These anti-inflammatory properties can be recapitulated with a fully recombinant preparation of appropriately sialylated I...
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.0810163105
更新日期:2008-12-16 00:00:00
abstract::The assembly of tiny magnetic particles in external magnetic fields is important for many applications ranging from data storage to medical technologies. The development of ever smaller magnetic structures is restricted by a size limit, where the particles are just barely magnetic. For such particles we report the dis...
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.1511443112
更新日期:2015-11-24 00:00:00
abstract::We have previously proven that human macrophages can phagocytose porcine cells even in the absence of Ab or complement opsonization, indicating that macrophages present a pivotal immunological obstacle to xenotransplantation. A recent report indicates that the signal regulatory protein (SIRP)alpha is a critical immune...
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.0609661104
更新日期:2007-03-20 00:00:00
abstract::Active immunization using tumor antigen-loaded dendritic cells holds promise for the adjuvant treatment of cancer to eradicate or control residual disease, but so far, most dendritic cell trials have been performed in end-stage cancer patients with high tumor loads. Here, in a phase I/II trial, we investigated the eff...
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.1008051107
更新日期:2010-08-03 00:00:00
abstract::Four major neutralizing regions of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein were identified and characterized with a panel of 80 HIV-1 antibody-positive human sera. Levels of neutralizing antibodies against the HIV-1 strains IIIB, SF2, and RF were compared with reactivity in ELISAs against...
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.89.2.461
更新日期:1992-01-15 00:00:00
abstract::Myosin-binding protein C (MyBP-C) is an accessory protein of striated muscle thick filaments and a modulator of cardiac muscle contraction. Defects in the cardiac isoform, cMyBP-C, cause heart disease. cMyBP-C includes 11 Ig- and fibronectin-like domains and a cMyBP-C-specific motif. In vitro studies show that in addi...
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.1316001111
更新日期:2014-02-11 00:00:00
abstract::Protein misfolding and aggregation cause serious degenerative conditions such as Alzheimer's, Parkinson, and prion diseases. Damage to membranes is thought to be one of the mechanisms underlying cellular toxicity of a range of amyloid assemblies. Previous studies have indicated that amyloid fibrils can cause membrane ...
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.1206325109
更新日期:2012-12-11 00:00:00
abstract::The configurations of the hydrocarbon chains in micelles are severely constrained by the space-filling requirements of the chain segments, by the continuity of the chains, and by the micellar geometry. A statistical theory that takes full account of these constraints is developed by using a lattice model. The chain en...
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.78.2.676
更新日期:1981-02-01 00:00:00
abstract::A glnB gene is identified in the cyanobacterium Synechococcus sp. PCC 7942, and its gene product is found to be covalently modified as a result of imbalance in electron transfer in photosynthesis, where photosystem II is favored over photosystem I. The gene was cloned and sequenced and found to encode a polypeptide of...
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.88.11.4565
更新日期:1991-06-01 00:00:00
abstract::NRSF/REST is a protein that silences transcription of a number of genes that contain a DNA element called the neuron-restrictive silencer element (NRSE). During embryogenesis, REST is expressed ubiquitously in nonneural cells, but is down-regulated during differentiation of neural progenitors into neurons. REST is als...
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.050578797
更新日期:2000-02-29 00:00:00
abstract::Cells of the human embryonic stem (hES) cell line H9, when cultured in the form of embryoid bodies, give rise to cells with markers of the keratinocyte of stratified squamous epithelia. Keratinocytes also form in nodules produced in scid mice by injected H9 cells; the hES-derived keratinocytes could be recovered in cu...
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.0510953103
更新日期:2006-02-07 00:00:00
abstract::Recent studies investigating the relationship between crop genetic diversity and human cultural diversity patterns showed that seed exchanges are embedded in farmers' social organization. However, our understanding of the social processes involved remains limited. We investigated how farmers' membership in three major...
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.1513238112
更新日期:2016-01-05 00:00:00
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::Immigration and demographic change have become highly salient in American politics, partly because of the 2016 campaign of Donald Trump. Previous research indicates that local influxes of immigrants or unfamiliar ethnic groups can generate threatened responses, but has either focused on nonelectoral outcomes or analyz...
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.1909202116
更新日期:2019-12-10 00:00:00
abstract::Recent evidence indicates there is a role for small membrane vesicles, including exosomes, as vehicles for intercellular communication. Exosomes secreted by most cell types can mediate transfer of proteins, mRNAs, and microRNAs, but their role in the transmission of infectious agents is less established. Recent 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.1221899110
更新日期:2013-08-06 00:00:00
abstract::Glucocorticoids are commonly used antiinflammatory agents whose use is limited by side effects. We have developed a series of glucocorticoid receptor (GR) ligands that retain the strong antiinflammatory activity of conventional glucocorticoids with reduced side effects. We present a compound, LGD5552, that binds the r...
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.0705517104
更新日期:2007-12-04 00:00:00
abstract::Learning to read requires the acquisition of an efficient visual procedure for quickly recognizing fine print. Thus, reading practice could induce a perceptual learning effect in early vision. Using functional magnetic resonance imaging (fMRI) in literate and illiterate adults, we previously demonstrated an impact of ...
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.1417347111
更新日期:2014-12-09 00:00:00
abstract::Across phyla, the ribosomes-the central molecular machines for translation of genetic information-exhibit an overall preserved architecture and a conserved functional core. The natural heterogeneity of the ribosome periodically phases a debate on their functional specialization and the tissue-specific variations of 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.1912060116
更新日期:2019-11-05 00:00:00
abstract::Cell adhesion molecules (CAMs) may act as regulators of morphogenesis by constraining cell motion, forming borders, and controlling intercellular communications that lead to embryonic induction. This postulated causal role of CAMs in inductive events was tested here in an in vitro system of feather induction. In the d...
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.83.21.8235
更新日期:1986-11-01 00:00:00
abstract::We have cloned and completely sequenced a gene encoding the heavy chain of Dictyostelium myosin I. Like the myosin I molecules from Acanthamoeba, the Dictyostelium myosin I heavy chain is composed of a globular head domain fused to a 45-kDa glycine-, proline-, and alanine-rich carboxyl-terminal domain, rather than 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.86.16.6186
更新日期:1989-08-01 00:00:00
abstract::We describe the use of a series of gradually expanded thymine nucleobase analogs in probing steric effects in DNA polymerase efficiency and fidelity. In these nonpolar compounds, the base size was increased incrementally over a 1.0-A range by use of variably sized atoms (H, F, Cl, Br, and I) to replace the oxygen mole...
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.0505113102
更新日期:2005-11-01 00:00:00
abstract::Cytotoxic T lymphocyte antigen-4 (CTLA-4) is essential for immunological (self-) tolerance, but due to the early fatality of CTLA-4 KO mice, its specific function in central and peripheral tolerance and in different systemic diseases remains to be determined. Here, we further examined the role of CTLA-4 by abrogating ...
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.1603892113
更新日期:2016-04-26 00:00:00
abstract::Turkey erythrocyte membranes showed specific binding of [(3)H]epinephrine. The concentration of hormone required for half-maximal binding (30 muM) was the same as that required for half-maximal activation of the adenylate cyclase located in the same membrane preparation. The binding reaction at 37 degrees C reached co...
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.69.2.523
更新日期:1972-02-01 00:00:00
abstract::Cytochrome c oxidase (ferrocytochrome c: oxygen oxidoreductase, EC 1.9.3.1) has been resolved into a pair of complexes of unequal molecular weight. The larger complex (electron transfer complex) contains exclusively the oxidation-reduction proteins characteristic of cytochrome oxidase; the smaller complex (ion transfe...
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.75.12.5908
更新日期:1978-12-01 00:00:00
abstract::Pulmonary pathologies including adult respiratory distress syndrome are characterized by disruption of pulmonary integrity and edema compromising respiratory function. Sphingosine 1-phosphate (S1P) is a lipid mediator synthesized and/or stored in mast cells, platelets, and epithelial cells, with production up-regulate...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,收录出版
doi:10.1073/pnas.0501997102
更新日期:2005-06-28 00:00:00
abstract::Synchronized beating of cilia on multiciliated cells (MCCs) generates a directional flow of mucus across epithelia. This motility requires a "9 + 2" microtubule (MT) configuration in axonemes and the unidirectional array of basal bodies of cilia on the MCCs. However, it is not fully understood what components are need...
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.1907335117
更新日期:2020-06-16 00:00:00
abstract::In the antennal lobe of Drosophila, information about odors is transferred from olfactory receptor neurons (ORNs) to projection neurons (PNs), which then send axons to neurons in the lateral horn of the protocerebrum (LHNs) and to Kenyon cells (KCs) in the mushroom body. The transformation from ORN to PN responses can...
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.1005635107
更新日期:2010-06-08 00:00:00
abstract::Aberrant transcription of the pericentromeric human satellite II (HSATII) repeat is present in a wide variety of epithelial cancers. In deriving experimental systems to study its deregulation, we observed that HSATII expression is induced in colon cancer cells cultured as xenografts or under nonadherent conditions in ...
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.1518008112
更新日期:2015-12-08 00:00:00