Abstract:
:Viral membrane fusion proteins of class I are trimers in which the protomeric unit is a complex of a surface subunit (SU) and a fusion active transmembrane subunit (TM). Here we have studied how the protomeric units of Moloney murine leukemia virus envelope protein (Env) are activated in relation to each other, sequentially or simultaneously. We followed the isomerization of the SU-TM disulfide and subsequent SU release from Env with biochemical methods and found that this early activation step occurred sequentially in the three protomers, generating two asymmetric oligomer intermediates according to the scheme (SU-TM)3 → (SU-TM)2TM → (SU-TM)TM2 → TM3 This was the case both when activation was triggered in vitro by depleting stabilizing Ca2+ from solubilized Env and when viral Env was receptor triggered on rat XC cells. In the latter case, the activation reaction was too fast for direct observation of the intermediates, but they could be caught by alkylation of the isomerization active thiol.
journal_name
Proc Natl Acad Sci U S Aauthors
Sjöberg M,Löving R,Lindqvist B,Garoff Hdoi
10.1073/pnas.1617264114subject
Has Abstractpub_date
2017-03-07 00:00:00pages
2723-2728issue
10eissn
0027-8424issn
1091-6490pii
1617264114journal_volume
114pub_type
杂志文章abstract::Oocyte endowment dwindles away during prepubertal and adult life until menopause occurs, and apoptosis has been identified as a central mechanism responsible for oocyte elimination. A few recent reports suggest that uncontrolled inflammation may adversely affect ovarian reserve. We tested the possible role of the proi...
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.1323955111
更新日期:2014-08-26 00:00:00
abstract::Climate change impacts island communities all over the world. Sea-level rise, an increase in the frequency and intensity of severe weather events, and changes in distribution and health of marine organisms are among the most significant processes affecting island communities worldwide. On islands of the Caribbean and ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.1914211117
更新日期:2020-04-14 00:00:00
abstract::Mesenchymal stromal stem cells (MSCs) isolated from adult tissues offer tangible potential for regenerative medicine, given their feasibility for autologous transplantation. MSC research shows encouraging results in experimental stroke, amyotrophic lateral sclerosis, and neurotrauma models. However, further translatio...
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.1616340114
更新日期:2017-01-31 00:00:00
abstract::Signaling pathways regulating proliferation, differentiation, and apoptosis are commonly mediated through protein-protein interactions as well as reversible phosphorylation of proteins. To facilitate the study of regulated protein-protein interactions in cells and living animals, we optimized firefly luciferase protei...
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.0404041101
更新日期:2004-08-17 00:00:00
abstract::The transcription factors that act in hepatocyte-specific gene expression include proteins that are present mainly in liver cells (HNF-1/LFB1, C/EBP, HNF-3, HNF-4) (HNF, hepatocyte nuclear factor; C/EBP, rat enhancer binding protein) and proteins that are widely distributed (AP-1, NF-1, NF-Y/ACF). We show here that 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.88.9.3807
更新日期:1991-05-01 00:00:00
abstract::An earthquake of magnitude M and linear source dimension L(M) is preceded within a few years by certain patterns of seismicity in the magnitude range down to about (M - 3) in an area of linear dimension about 5L-10L. Prediction algorithms based on such patterns may allow one to predict approximately 80% of strong eart...
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.93.9.3748
更新日期:1996-04-30 00:00:00
abstract::In this model gravitation results from the emission and absorption of quanta (gravitons) that are scattered a few times in crossing a typical galaxy. Many features of the universe can be explained in terms of this model, although theoretical justification for the scattering of gravitons is lacking. Gravitons follow 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.89.9.4086
更新日期:1992-05-01 00:00:00
abstract::T-cell tumors are characterized by inversions or translocations of chromosome 14. The breakpoints of these karyotypic abnormalities occur in chromosome bands 14q11 and 14q32--the same bands in which the T-cell receptor (TCR) alpha-chain and immunoglobulin heavy chain genes have been mapped, respectively. Patients with...
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.84.24.9069
更新日期:1987-12-01 00:00:00
abstract::Burkitt's lymphomas, linked by previous studies with the DNA-containing Epstein-Barr virus, contain an RNA related in sequence to that of Rauscher leukemia virus. The present study establishes that the viral-related RNA found in Burkitt's tumors is a 70S component encapsulated with RNA-instructed DNA polymerase in a p...
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.70.3.737
更新日期:1973-03-01 00:00:00
abstract::Heparanase is an endoglycosidase that cleaves heparan sulfate side chains of proteoglycans, resulting in disassembly of the extracellular matrix underlying endothelial and epithelial cells and associating with enhanced cell invasion and metastasis. Heparanase expression is induced in carcinomas and sarcomas, often 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.1519453113
更新日期:2016-01-19 00:00:00
abstract::Formation of G-quadruplex (G4) DNA structures in key regulatory regions in the genome has emerged as a secondary structure-based epigenetic mechanism for regulating multiple biological processes including transcription, replication, and telomere maintenance. G4 formation (folding), stabilization, and unfolding must be...
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.1912355117
更新日期:2020-05-26 00:00:00
abstract::The species-area relationship (SAR) gives a quantitative description of the increasing number of species in a community with increasing area of habitat. In conservation, SARs have been used to predict the number of extinctions when the area of habitat is reduced. Such predictions are most needed for landscapes rather ...
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.1311491110
更新日期:2013-07-30 00:00:00
abstract::Terrorist attacks often fuel online hate and increase the expression of xenophobic and antiminority messages. Previous research has focused on the impact of terrorist attacks on prejudiced attitudes toward groups linked to the perpetrators as the cause of this increase. We argue that social norms can contain the expre...
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.2007977117
更新日期:2020-09-15 00:00:00
abstract::It is becoming common practice to partition glass-forming liquids into two classes based on the dependence of the shear viscosity η on temperature T. In an Arrhenius plot, ln η vs 1/T, a strong liquid shows linear behavior whereas a fragile liquid exhibits an upward curvature [super-Arrhenius (SA) behavior], a situati...
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.1015340107
更新日期:2010-12-28 00:00:00
abstract::Cognitive flexibility depends on a fast neural learning mechanism for enhancing momentary relevant over irrelevant information. A possible neural mechanism realizing this enhancement uses fast spiking interneurons (FSIs) in the striatum to train striatal projection neurons to gate relevant and suppress distracting cor...
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.2001348117
更新日期:2020-07-28 00:00:00
abstract::We have isolated an Arabidopsis thaliana gene that codes for a receptor related to antifungal pathogenesis-related (PR) proteins. The PR5K gene codes for a predicted 665-amino acid polypeptide that comprises an extracellular domain related to the PR5 proteins, a central transmembrane-spanning domain, and an intracellu...
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.93.6.2598
更新日期:1996-03-19 00:00:00
abstract::Cell cycle checkpoints appear to contribute to an increase in cell survival and a decrease in abnormal heritable genetic changes following exposure to DNA damaging agents. Though several radiation-sensitive yeast mutants have been identified, little is known about the genes that control these responses in mammalian ce...
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.89.16.7491
更新日期:1992-08-15 00:00:00
abstract::Two deletion-substitution mutations of phage lambda, spi-113 and spi-274, are shown to remove about half of the rightward operator OR. Physiological studies show that spi-113 is still repressible. Thus, the 50 or so nucleotides of OR deleted in this mutant are not absolutely essential for repression. prm-116, which 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.73.3.712
更新日期:1976-03-01 00:00:00
abstract::The goal of the current study was to investigate the role of exogenous and endogenous hydrogen sulfide (H(2)S) on neovascularization and wound healing in vitro and in vivo. Incubation of endothelial cells (ECs) with H(2)S enhanced their angiogenic potential, evidenced by accelerated cell growth, migration, and capilla...
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.0908047106
更新日期:2009-12-22 00:00:00
abstract::A spherical harmonic analysis is made of the hydrodynamic equation governing the flow of an incompressible liquid in a rotating sphere in the presence of the magnetic Lorentz force. Nonlinear partial differential equations are derived for the functions S(n)(r,t) and T(n)(r,t) entering the spherical harmonic representa...
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.72.4.1496
更新日期:1975-04-01 00:00:00
abstract::In Drosophila, multiple isoforms of alpha-glycerol-3-phosphate dehydrogenase (sn-glycerol-3-phosphate: NAD+ 2-oxidoreductase, EC 1.1.1.8) are produced in a tissue- and stage-specific manner. To understand the underlying molecular basis of these isoforms, we have sequenced a 5.8-kilobase region of the Drosophila genome...
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.86.13.5020
更新日期:1989-07-01 00:00:00
abstract::A varying oxygen environment is known to affect cellular function in disease as well as activity of various therapeutics. For transient structures, whether they are unconstrained therapeutic transplants, migrating cells during tumor metastasis, or cell populations induced by an immunological response, the role of oxyg...
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.1815909116
更新日期:2019-03-12 00:00:00
abstract::Five DNA fragments have been cloned from yeast, chicken, and mouse DNA that titrate lac repressor in an Escherichia coli lac+ I+Z+ wild-type strain when on a multi-copy plasmid. The five repressor-binding sequences have been identified by DNA sequence determinations and DNase cleavage-inhibition patterns. They share 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.81.6.1624
更新日期:1984-03-01 00:00:00
abstract::Cytokines such as interleukin 4 (IL-4) play a key role in the regulation of immune responses, but little is known about how their multiple activities are regulated in vivo. In this report, we demonstrated that an IL-4-binding protein (IL-4BP) is constitutively present in the biological fluids of mice (serum, ascites, ...
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.87.11.4202
更新日期:1990-06-01 00:00:00
abstract::Analogy-the ability to find and apply deep structural patterns across domains-has been fundamental to human innovation in science and technology. Today there is a growing opportunity to accelerate innovation by moving analogy out of a single person's mind and distributing it across many information processors, both hu...
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.1807185116
更新日期:2019-02-05 00:00:00
abstract::Understanding the effects of the external environment on bacterial gene expression can provide valuable insights into an array of cellular mechanisms including pathogenesis, drug resistance, and, in the case of Mycobacterium tuberculosis, latency. Because of the absence of poly(A)+ mRNA in prokaryotic organisms, studi...
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.95.22.13227
更新日期:1998-10-27 00:00:00
abstract::Endogenous circadian rhythms have been described in a wide range of organisms from prokaryotes to man. Although basic circadian mechanisms at the molecular level are genetically fixed, certain properties of circadian rhythms at the organismic level can be modified by environmental conditions and subsequently retained ...
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.200354997
更新日期:2000-10-24 00:00:00
abstract::The initiator RNAs of mammalian Okazaki fragments are thought to be removed by RNase HI and the 5'-3' flap endonuclease (FEN1). Earlier evidence indicated that the cleavage site of RNase HI is 5' of the last ribonucleotide at the RNA-DNA junction on an Okazaki substrate. In current work, highly purified calf RNase HI ...
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.95.5.2244
更新日期:1998-03-03 00:00:00
abstract::The transcription of genes encoding gluconeogenic enzymes is tightly regulated during the perinatal period. These genes are induced by glucagon (cAMP) and glucocorticoids and repressed by insulin. To address the role of cAMP and glucocorticoids in the physiological activation of genes encoding gluconeogenic enzymes 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.92.10.4244
更新日期:1995-05-09 00:00:00
abstract::The suppressor of Hairy-wing [su(Hw)] protein exerts a polar effect on gene expression by repressing the function of transcriptional enhancers located distally from the promoter with respect to the location of su(Hw) binding sequences. The directionality of this effect suggests that the su(Hw) protein specifically int...
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.92.11.5184
更新日期:1995-05-23 00:00:00