Abstract:
:A class II (B) general transcription factor of 34 kDa has been purified from HeLa cells to apparent homogeneity. This factor appears to be transcription factor IIB (TFIIB), since it binds in vitro to template-committed preinitiation complexes formed between a template containing the TATA box/cap-site elements of the adenovirus type 2 major late promoter (Ad2MLP) and recombinant human or yeast TFIID (previously called BTF1) expressed in Escherichia coli. DNase I footprint studies show an extended pattern of protection of Ad2MLP TATA box/cap-site sequences when TFIIB is bound to template-committed complexes, even though TFIIB does not bind on its own to the template in the absence of TFIID. We also show that TFIIB is different from BTF3 by a number of criteria.
journal_name
Proc Natl Acad Sci U S Aauthors
Moncollin V,Fischer L,Cavallini B,Egly JM,Chambon Pdoi
10.1073/pnas.89.1.397subject
Has Abstractpub_date
1992-01-01 00:00:00pages
397-401issue
1eissn
0027-8424issn
1091-6490journal_volume
89pub_type
杂志文章abstract::Hypophosphatasia is a heritable form of rickets/osteomalacia with extremely variable clinical expression. Severe forms are inherited in an autosomal recessive fashion; the mode of transmission of mild forms is uncertain. The biochemical hallmark of hypophosphatasia is deficient activity of the tissue-nonspecific isozy...
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.89.20.9924
更新日期:1992-10-15 00:00:00
abstract::To investigate whether caveolin-1 (cav-1) may modulate inducible nitric oxide synthase (iNOS) function in intact cells, the human intestinal carcinoma cell lines HT29 and DLD1 that have low endogenous cav-1 levels were transfected with cav-1 cDNA. In nontransfected cells, iNOS mRNA and protein levels were increased by...
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.250406797
更新日期:2000-12-19 00:00:00
abstract::A study of behavior and structure indicates that highly eusocial behavior arose twice in the bees--i.e., in the stingless bees (Meliponinae) and in the honeybees (Apinae). Morphological features demonstrate the distinctiveness of these two groups and the relationship of the latter to bumblebees (Bombini) and orchid 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.74.3.1135
更新日期:1977-03-01 00:00:00
abstract::How does genome evolution affect the rate of diversification of biological lineages? Recent studies have suggested that the overall rate of genome evolution is correlated with the rate of diversification. If true, this claim has important consequences for understanding the process of diversification, and implications ...
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.1007888107
更新日期:2010-11-23 00:00:00
abstract::Coiled-coil motifs are ubiquitous mediators of specific protein-protein interactions through the formation of interlocking hydrophobic seams between alpha-helical chains. Residues that form these seams occur at the first (a) and fourth (d) positions of a characteristic 7-aa repeat and are primarily aliphatic. The pote...
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.0405319101
更新日期:2004-11-16 00:00:00
abstract::A new type of self-assembling peptide (sapeptide) scaffolds that serve as substrates for neurite outgrowth and synapse formation is described. These peptide-based scaffolds are amenable to molecular design by using chemical or biotechnological syntheses. They can be tailored to a variety of applications. The sapeptide...
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.97.12.6728
更新日期:2000-06-06 00:00:00
abstract::We searched for germ-line mutations of the APC gene in 79 unrelated patients with familial adenomatous polyposis using a ribonuclease protection analysis coupled with polymerase chain reaction amplifications of genomic DNA. Mutations were found in 53 patients (67%); 28 of the mutations were small deletions and 2 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.89.10.4452
更新日期:1992-05-15 00:00:00
abstract::A human Burkitt lymphoma cell line, Raji-HN2, made 10-fold more resistant to nitrogen mustard (HN2) than the parental Raji cell line, exhibited the following characteristics when compared to the parental Raji cells: (i) decreased HN2-induced DNA interstrand crosslinking; (ii) increased (3-fold) DNA topoisomerase II [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.84.21.7668
更新日期:1987-11-01 00:00:00
abstract::Tobacco mosaic virus and turnip yellow mosaic virus genome RNAs, which have long (greater than or equal to 69 nucleotides) 5'-terminal leader sequences preceding the AUG initiation codon, can form disome initiation complexes when incubated with a wheat germ extract and sparsomycin. In tobacco mosaic virus RNA, 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.76.7.3111
更新日期:1979-07-01 00:00:00
abstract::Combinatorial antibody libraries have the potential to display the entire immunological record of an individual, allowing one to detect and recover any antibody ever made, irrespective of whether it is currently being produced. We have termed this the "fossil record" of an individual's antibody response. To determine ...
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.0407869101
更新日期:2004-12-07 00:00:00
abstract::The bacterial pathogen Helicobacter pylori chronically infects the human gastric mucosa and is the leading risk factor for the development of gastric cancer. The molecular mechanisms of H. pylori-associated gastric carcinogenesis remain ill defined. In this study, we examined the possibility that H. pylori directly 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.1100959108
更新日期:2011-09-06 00:00:00
abstract::Human neutrophils respond to chemoattractants, resulting in their accumulation at an inflammatory site. Chemoattractants such as the C5a peptide, derived from the C5 complement factor, bind to inhibitory guanine nucleotide binding protein (Gi)-coupled seven membrane-spanning receptors expressed in neutrophils. C5a rec...
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.91.19.9190
更新日期:1994-09-13 00:00:00
abstract::Proteins of ribosomes from various stages of development in Dictyostelium discoideum were analyzed by two-dimensional polyacrylamide gel electrophoresis. Significant changes in protein composition were observed; the data demonstrate that cell differentiation in a eukaryotic system is accompanied by ribosome heterogene...
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.78.5.3083
更新日期:1981-05-01 00:00:00
abstract::The Tat protein coded by human immunodeficiency virus (HIV) is a strong activator of viral gene expression from the long terminal repeat (LTR). It appears that Tat-mediated trans-activation of the HIV LTR is predominantly a transcriptional event. It has been reported that Tat acts at the level of both transcriptional ...
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.88.19.8510
更新日期:1991-10-01 00:00:00
abstract::Brood parasitism as an alternative female breeding tactic is particularly common in ducks, where hosts often receive eggs laid by parasitic females of the same species and raise their offspring. Herein, we test several aspects of a kin selection explanation for this phenomenon in goldeneye ducks (Bucephala clangula) b...
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.220137897
更新日期:2000-11-21 00:00:00
abstract::A transformation-defective mutant of Abelson murine leukemia virus (A-MuLV), called A-MuLV-P92td, has been isolated. The mutant encodes a serologically identifiable A-MuLV protein of molecular weight 92,000 (P92) but it lacks the ability to transform either fibroblasts or bone marrow lymphoid cells. In contrast to 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.77.8.4993
更新日期:1980-08-01 00:00:00
abstract::The genomic basis of primate phenotypic uniqueness remains obscure, despite increasing genome and transcriptome sequence data availability. Although factors such as segmental duplications and positive selection have received much attention as potential drivers of primate phenotypes, single-copy primate-specific genes ...
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.0904569106
更新日期:2009-07-21 00:00:00
abstract::Wild and managed bees are well documented as effective pollinators of global crops of economic importance. However, the contributions by pollinators other than bees have been little explored despite their potential to contribute to crop production and stability in the face of environmental change. Non-bee pollinators ...
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.1517092112
更新日期:2016-01-05 00:00:00
abstract::Biologists regularly search databases of DNA or protein sequences for evolutionary or functional relationships to a given query sequence. We describe a ranking algorithm that exploits the entire network structure of similarity relationships among proteins in a sequence database by performing a diffusion operation on 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.0308067101
更新日期:2004-04-27 00:00:00
abstract::Nonenzymatic manganese was first shown to provide protection against superoxide toxicity in vivo in 1981, but the chemical mechanism responsible for this protection subsequently became controversial due to conflicting reports concerning the ability of Mn to catalyze superoxide disproportionation in vitro. In a recent ...
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.1203051109
更新日期:2012-05-01 00:00:00
abstract::A Raleigh, NC, population of Drosophila melanogaster was sampled for the presence of enzyme null alleles at 25 loci. No nulls were found at any of five X-linked loci. Nulls were recovered at 13 of 20 autosomal loci; the weighted mean frequency for all 20 autosomal loci was estimated to be 0.0025. A consideration 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.77.2.1091
更新日期:1980-02-01 00:00:00
abstract::A key feature of immune evasion for African trypanosomes is the functional specialization of their surface membrane in an invagination known as the flagellar pocket (FP), the cell's sole site of endocytosis and exocytosis. The FP membrane is biochemically distinct yet continuous with those of the cell body and the fla...
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.0909289106
更新日期:2009-10-13 00:00:00
abstract::Rat liver glutamine synthetase (s(20,w) 15.0 S; MW about 352,000) resembles ovine brain glutamine synthetase in that it (a) has 8 subunits, (b) acts on both L- and D-glutamate and certain glutamate analogs (e.g., beta-glutamate, cis-cycloglutamate, and alpha-methyl-L-glutamate), and (c) is irreversibly inhibited by L-...
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.68.4.781
更新日期:1971-04-01 00:00:00
abstract::We have assayed carbonic anhydrase activity (carbonate dehydratase, carbonate hydro-lyase, EC 4.2.1.1) and bicarbonate permeability in suspensions of broken and intact guinea pig mitochondria by monitoring the disappearance of C16O18O. We found significant activity in preparations from liver and skeletal muscle, but n...
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.77.9.5562
更新日期:1980-09-01 00:00:00
abstract::Responses of tethered cells of Escherichia coli to impulse, step, exponential-ramp or exponentiated sine-wave stimuli are internally consistent, provided that allowance is made for the nonlinear effect of thresholds. This result confirms that wild-type cells exposed to stimuli in the physiological range make short-ter...
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.83.23.8987
更新日期:1986-12-01 00:00:00
abstract::Pyrimethamine (Pyr) targets dihydrofolate reductase of Plasmodium vivax (PvDHFR) as well as other malarial parasites, but its use as antimalarial is hampered by the widespread high resistance. Comparison of the crystal structures of PvDHFR from wild-type and the Pyr-resistant (SP21, Ser-58 --> Arg + Ser-117 --> Asn) s...
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.0501747102
更新日期:2005-09-13 00:00:00
abstract::In vivo phage display identifies peptides that selectively home to the vasculature of individual organs, tissues, and tumors. Here we report the identification of a cyclic nonapeptide, CPGPEGAGC, which homes to normal breast tissue with a 100-fold selectivity over nontargeted phage. The homing of the phage is inhibite...
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.251687998
更新日期:2002-02-19 00:00:00
abstract::The mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most destructive pest of western North American pine forests. Adult males produce frontalin, an eight-carbon antiaggregation pheromone, via the mevalonate pathway, as part of several pheromones that initiate and modulate the mass attack of host trees. 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.1316498110
更新日期:2013-11-19 00:00:00
abstract::There are at least three short-range gap repressors in the precellular Drosophila embryo: Krüppel, Knirps, and Giant. Krüppel and Knirps contain related repression motifs, PxDLSxH and PxDLSxK, respectively, which mediate interactions with the dCtBP corepressor protein. Here, we present evidence that Giant might also 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.111158298
更新日期:2001-05-22 00:00:00
abstract::Glutamine-dependent carbamylphosphate synthetase (Escherichia coli) is composed of a heavy subunit (molecular weight about 130,000) and a light subunit (molecular weight about 42,000), which can be separated with retention of catalytic activities. The separated heavy subunit can catalyze activation of CO(2) by ATP 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.70.10.2717
更新日期:1973-10-01 00:00:00