Abstract:
:The gene V protein of bacteriophage f1 is a single-stranded DNA and RNA-binding protein composed of two identical subunits. We have constructed single-chain variants of the protein using short peptide linkers of five or six amino acids to connect the carboxyl terminus of one monomer to the amino terminus of the second monomer. The resulting subunit-fusion gene V proteins were found to bind single-stranded DNA nearly as tightly as the wild-type protein. Denaturation measurements show that the subunit-fusion gene V proteins are 5 kcal/mol (1 kcal = 4.18 kJ) more stable than the wild-type protein at a protein concentration of 10 microM. The rate of unfolding of the protein is essentially unaffected by the fusion of monomeric subunits, whereas the rate of folding is greatly enhanced. Our results suggest a simple way of obtaining a substantial thermodynamic stabilization for some oligomeric proteins.
journal_name
Proc Natl Acad Sci U S Aauthors
Liang H,Sandberg WS,Terwilliger TCdoi
10.1073/pnas.90.15.7010subject
Has Abstractpub_date
1993-08-01 00:00:00pages
7010-4issue
15eissn
0027-8424issn
1091-6490journal_volume
90pub_type
杂志文章abstract::Excessive activation of calmodulin kinase II (CaMKII) causes arrhythmias and heart failure, but the cellular mechanisms for CaMKII-targeted proteins causing disordered cell membrane excitability and myocardial dysfunction remain uncertain. Failing human cardiomyocytes exhibit increased CaMKII and voltage-gated Ca(2+) ...
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.0913760107
更新日期:2010-03-16 00:00:00
abstract::Appropriate expression of IL-2 plays a central role during the priming and differentiation of T cells. A tight balance between IL-2 and the effector cytokine IL-17A is essential for immune homeostasis. Epigenetic mechanisms have been documented as a key component of cytokine regulation during lineage commitment. The m...
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.1210129109
更新日期:2012-10-09 00:00:00
abstract::Mutant Escherichia coli strains in which export of the LamB protein (coded for by the lamB gene) to the outer membrane of the cell is prevented have been described previously. One of these mutant strains contains a small (12-base pair) deletion mutation within the region of the lamB gene that codes for the NH2-termina...
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.80.15.4599
更新日期:1983-08-01 00:00:00
abstract::We have recently determined that high calcium concentrations, in parallel with their suppressive effects on parathyroid hormone (PTH) secretion, reversibly and specifically decrease preproPTH mRNA in cultured bovine parathyroid cells. In order to determine whether vitamin D metabolites also regulate the content of pre...
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.82.12.4270
更新日期:1985-06-01 00:00:00
abstract::Paired oxygen-isotopic analyses of abiotic carbonate and benthic-ostracode shells from lake sediments provide a continuous quantitative record of growing-season temperature for the past 2000 years in the northwestern foothills of the Alaska Range. This record reveals three time intervals of comparable warmth: anno Dom...
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.181333798
更新日期:2001-09-11 00:00:00
abstract::The C terminus of transcription factor NusA from Escherichia coli comprises two repeat units, which bind during antitermination to protein N from phage lambda. To delineate the structural basis of the NusA-lambdaN interaction, we attempted to crystallize the NusA C-terminal repeats in complex with a lambdaN peptide (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.0405883101
更新日期:2004-09-21 00:00:00
abstract::In the presence but not in the absence of pokeweed mitogen (PWM), monoclonal antibodies against HLA-DR antigens 147 and 164 helped highly purified B lymphocytes to proliferate and mature to Ig-secreting cells. In contrast, neither anti-DR antibody 231 nor the UCHT1 monoclonal anti-human T cell antibody (both of the sa...
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.80.11.3456
更新日期:1983-06-01 00:00:00
abstract::A study has been made of Cauchy's problem for a class of abstract parabolic differential equations. Our study is based upon a transformation that maps solutions of second-order abstract Cauchy problems into solutions of first-order. This is a preliminary report on some of the results obtained. These results include (1...
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.68.9.2025
更新日期:1971-09-01 00:00:00
abstract::Significant efforts have been directed to understanding the factors that influence the lineage commitment of stem cells. This paper demonstrates that cell shape, independent of soluble factors, has a strong influence on the differentiation of human mesenchymal stem cells (MSCs) from bone marrow. When exposed to compet...
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.0903269107
更新日期:2010-03-16 00:00:00
abstract::Procedures are described for the isolation of conditional lethal mutants of mouse L-60T cells. The mutant lines were temperature sensitive by the following criteria: (a) colony-forming ability, (b) growth in suspension culture, and (c) rate of uptake of tritiated-thymidine. ...
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.66.2.377
更新日期:1970-06-01 00:00:00
abstract::Look-through mutagenesis (LTM) is a multidimensional mutagenesis method that simultaneously assesses and optimizes combinatorial mutations of selected amino acids. The process focuses on a precise distribution within one or more complementarity determining region (CDR) domains and explores the synergistic contribution...
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.0503543102
更新日期:2005-06-14 00:00:00
abstract::Sea urchins are a major component of recent marine communities where they exert a key role as grazers and benthic predators. However, their impact on past marine organisms, such as crinoids, is hard to infer in the fossil record. Analysis of bite mark frequencies on crinoid columnals and comprehensive genus-level dive...
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.1201573109
更新日期:2012-05-01 00:00:00
abstract::This study challenges the paradigm that salt marsh plants prevent lateral wave-induced erosion along wetland edges by binding soil with live roots and clarifies the role of vegetation in protecting the coast. In both laboratory flume studies and controlled field experiments, we show that common salt marsh plants do no...
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.0901297106
更新日期:2009-06-23 00:00:00
abstract::The ability of specific gangliosides to function as host cell receptors for Sendai virus was investigated by using Madin-Darby bovine kidney cells which become resistant to infection upon treatment with Vibrio cholerae sialidase. Sialidase-treated cells were incubated for 20 min at 37 degrees C with individual, highly...
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.78.9.5406
更新日期:1981-09-01 00:00:00
abstract::MicroRNAs (miRNAs) are small 19- to 24-nt noncoding RNAs that have the capacity to regulate fundamental biological processes essential for cancer initiation and progression. In cancer, miRNAs may function as oncogenes or tumor suppressors. Here, we conducted global profiling for miRNAs in a cohort of stage 1 nonsmall ...
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.1307107110
更新日期:2013-09-10 00:00:00
abstract::When the content of cyclic AMP (cAMP) was compared in livers of a series of congenic mouse strains differing at the H-2 locus, significant variation in concentration of cAMP per unit wet weight was found among strains, and also for animals of a given strain with increasing age. For a given age, from 8 to 22 weeks, cAM...
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.72.7.2644
更新日期:1975-07-01 00:00:00
abstract::Land-use change is a major driver of biodiversity loss worldwide. Although biodiversity often shows a delayed response to land-use change, previous studies have typically focused on a narrow range of current landscape factors and have largely ignored the role of land-use history in shaping plant and animal communities...
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.1910023117
更新日期:2020-01-21 00:00:00
abstract::CCAAT/enhancer-binding protein δ (C/EBPδ) recently emerged as an essential player in the inflammatory response to bacterial infections. C/EBPδ levels increase rapidly after a proinflammatory stimulus, and increasing C/EBPδ levels seem to be indispensable for amplification of the inflammatory response. Here we aimed to...
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.1202641109
更新日期:2012-06-05 00:00:00
abstract::Metabolic engineering seeks to reprogram microbial cells to efficiently and sustainably produce value-added compounds. Since chemical production can be at odds with the cell's natural objectives, strategies have been developed to balance conflicting goals. For example, dynamic regulation modulates gene expression to f...
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.1911144116
更新日期:2019-12-17 00:00:00
abstract::Point mutations in either of the two nucleotide-binding domains (NBD) of Hsp104 (NBD1 and NBD2) eliminate its thermotolerance function in vivo. In vitro, NBD1 mutations virtually eliminate ATP hydrolysis with little effect on hexamerization; analogous NBD2 mutations reduce ATPase activity and severely impair hexameriz...
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.031568098
更新日期:2001-01-30 00:00:00
abstract::Behavioral and neural evidence reveal a prospective goal-directed decision process that relies on mental simulation of the environment, and a retrospective habitual process that caches returns previously garnered from available choices. Artificial systems combine the two by simulating the environment up to some depth ...
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.1609094113
更新日期:2016-11-08 00:00:00
abstract::The rpoS gene of Escherichia coli encodes a putative RNA polymerase sigma factor that is considered to be the central regulator of gene expression in stationary phase. The gene product (sigma 38) was overproduced using the cloned rpoS gene and purified to homogeneity. Reconstituted RNA polymerase holoenzyme (E sigma 3...
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.90.8.3511
更新日期:1993-04-15 00:00:00
abstract::Biological membranes contain an extraordinary diversity of lipids. Phospholipids function as major structural elements of cellular membranes, and analysis of changes in the highly heterogeneous mixtures of lipids found in eukaryotic cells is central to understanding the complex functions in which lipids participate. 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.131195098
更新日期:2001-06-19 00:00:00
abstract::The nod (no distributive disjunction) and the ncd (non-claret disjunctional) mutations are both female-specific, recessive meiotic mutations in Drosophila melanogaster. Mutations at either locus show high frequencies of nondisjunction at meiosis I and both have been shown to encode kinesin-like proteins. Unlike the nc...
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.88.16.7165
更新日期:1991-08-15 00:00:00
abstract::The type 6 secretion system (T6SS) is a nanomachine used by many Gram-negative bacteria, including Vibrio cholerae, to deliver toxic effector proteins into adjacent eukaryotic and bacterial cells. Because the activity of the T6SS is dependent on direct contact between cells, its activity is limited to bacteria growing...
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.1808469115
更新日期:2018-07-31 00:00:00
abstract::We report the nucleotide sequences of iaaM and iaaH, the genetic determinants for, respectively, tryptophan 2-monooxygenase and indoleacetamide hydrolase, the enzymes that catalyze the conversion of L-tryptophan to indoleacetic acid in the tumor-forming bacterium Pseudomonas syringae pv. savastanoi. The sequence analy...
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.82.19.6522
更新日期:1985-10-01 00:00:00
abstract::Male infertility, affecting as many as 10% of the adult population, is an extremely prevalent disorder. In most cases, the cause of the condition is unknown, and genetic factors that might affect male fertility, other than some sequences on the Y chromosome, have not been identified. We report here that male mice hete...
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.93.20.10903
更新日期:1996-10-01 00:00:00
abstract::Exposure to childhood trauma (CT) increases the risk for psychosis and affects the development of brain structures, possibly through oxidative stress. As oxidative stress is also linked to psychosis, it may interact with CT, leading to a more severe clinical phenotype. In 133 patients with early psychosis (EPP), we ex...
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.1812821115
更新日期:2018-12-04 00:00:00
abstract::Heparin preparations from pig intestinal mucosa and from bovine lung were separated by chromatography on antithrombin-Sepharose into a high-affinity fraction (with high anticoagulant activity) and a low-affinity fraction (with low anticoagulant). Antithrombin-binding heparin fragments (12-16 monosaccharide units) were...
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.76.7.3198
更新日期:1979-07-01 00:00:00
abstract::Loss of the tumor suppressor, PTEN, is one of the most common findings in prostate cancer (PCa). This loss leads to overactive Akt signaling, which is correlated with increased metastasis and androgen independence. However, another tumor suppressor, inositol-polyphosphate 4-phosphatase type II (INPP4B), can partially ...
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.2007160117
更新日期:2020-10-20 00:00:00