Abstract:
:The rRNA intervening sequence of Tetrahymena is a catalytic RNA molecule, or "ribozyme." A tertiary-structure model of the active site of this ribozyme has been constructed based on comparative sequence analysis of related group I intervening sequences, data on the accessibility of each nucleotide to chemical and enzymatic probes, and principles of RNA folding derived from a consideration of the structure of tRNA determined by x-ray crystallography. In the model, the catalytic center has a two-helix structural framework composed of the base-paired segments of the group I conserved sequence elements. The structural framework supports and orients the conserved nucleotides that are adjacent to the base-paired sequence elements; these conserved nucleotides are proposed to form the active site and to bind the 5' splice-site duplex and the guanine nucleotide substrate. Tests of the model are proposed.
journal_name
Proc Natl Acad Sci U S Aauthors
Kim SH,Cech TRdoi
10.1073/pnas.84.24.8788subject
Has Abstractpub_date
1987-12-01 00:00:00pages
8788-92issue
24eissn
0027-8424issn
1091-6490journal_volume
84pub_type
杂志文章abstract::The unfolded protein response (UPR) is an evolutionarily conserved mechanism by which all eukaryotic cells adapt to the accumulation of unfolded proteins in the endoplasmic reticulum (ER). Inositol-requiring kinase 1 (IRE1) and PKR-related ER kinase (PERK) are two type I transmembrane ER-localized protein kinase recep...
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.0606480103
更新日期:2006-09-26 00:00:00
abstract::Ontogenetic changes in the protein phosphorylation/dephosphorylation systems in rat brain were investigated. It was found that the activity level of phospholipid-sensitive Ca2+-dependent protein kinase (PL-Ca-PK) in the particulate fraction of grey and white matter and the soluble fraction of grey matter increased rap...
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.81.10.3143
更新日期:1984-05-01 00:00:00
abstract::The Mediator complex forms the bridge between transcriptional activators and RNA polymerase II. Mediator subunit Med1/TRAP220 is a key component of Mediator originally found to associate with nuclear hormone receptors. Med1 deficiency causes lethality at embryonic day 11.5 because of defects in heart and placenta deve...
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.0604494103
更新日期:2006-12-05 00:00:00
abstract::Facial expressions of emotion in humans are believed to be produced by contracting one's facial muscles, generally called action units. However, the surface of the face is also innervated with a large network of blood vessels. Blood flow variations in these vessels yield visible color changes on the face. Here, we stu...
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.1716084115
更新日期:2018-04-03 00:00:00
abstract::Aging and disease processes may be due to deleterious and irreversible changes produced by free radical reactions. The enzyme copper-zinc superoxide dismutase (Cu-Zn SOD; superoxide:superoxide oxidoreductase, EC 1.15.1.1) performs a protective function by scavenging superoxide radicals. The Cu-Zn SOD gene (Sod) cloned...
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.87.11.4270
更新日期:1990-06-01 00:00:00
abstract::Multiple studies have established that microRNAs (miRNAs) are involved in the initiation and progression of cancer. Notably, miR-155 is one of the most overexpressed miRNAs in several solid and hematological malignancies. Ectopic miR-155 expression in mice B cells (Eμ-miR-155 transgenic mice) has been shown to induce ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,meta分析
doi:10.1073/pnas.1213764109
更新日期:2012-12-04 00:00:00
abstract::There is currently an unmet need for versatile techniques to monitor the assembly and dynamics of ternary complexes in live cells. Here we describe bioluminescence resonance energy transfer with fluorescence enhancement by combined transfer (BRETFect), a high-throughput technique that enables robust spectrometric dete...
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.1716224115
更新日期:2018-03-13 00:00:00
abstract::Ribozymes are RNAs that possess the dual properties of RNA sequence-specific recognition, analogous to conventional antisense molecules, and RNA substrate destruction via site-specific cleavage. The cleavage reaction is catalytic in that more than one substrate molecule is processed per ribozyme molecule. We have desi...
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.89.22.10802
更新日期:1992-11-15 00:00:00
abstract::Accumulative aggregation of mutant Huntingtin (Htt) is a primary neuropathological hallmark of Huntington's disease (HD). Currently, mechanistic understanding of the cytotoxicity of mutant Htt aggregates remains limited, and neuroprotective strategies combating mutant Htt-induced neurodegeneration are lacking. Here, w...
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.1904563116
更新日期:2019-09-17 00:00:00
abstract::Flow separation and vortex shedding are some of the most common phenomena experienced by bluff bodies under relative motion with the surrounding medium. They often result in a recirculation bubble in regions with adverse pressure gradient, which typically reduces efficiency in vehicles and increases loading on structu...
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.1715567115
更新日期:2018-02-06 00:00:00
abstract::We describe a functional profiling strategy to identify and characterize subtypes of neurons present in a peripheral ganglion, which should be extendable to neurons in the CNS. In this study, dissociated dorsal-root ganglion neurons from mice were exposed to various pharmacological agents (challenge compounds), while ...
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.1118833109
更新日期:2012-01-31 00:00:00
abstract::Antigen-independent cell lines were derived from mouse helper T-cell clones by culture in autologous supernatant obtained after stimulation with concanavalin A. A factor, termed P40, supporting the growth of these lines was purified and characterized as a basic 32- to 39-kDa single-chain glycoprotein functionally dist...
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.85.18.6934
更新日期:1988-09-01 00:00:00
abstract::We investigated the binding of 125I-labeled alpha-inhibin-92 (a 92-residue peptide) to human pituitary membrane preparations. Unlabeled alpha-inhibin-92 competed effectively with the labeled peptide for binding to the membranes. Binding was also inhibited by both alpha-inhibin-52 and alpha-inhibin-31, but less effecti...
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.84.11.3595
更新日期:1987-06-01 00:00:00
abstract::Male oriental fruit flies (Dacus dorsalis) from colonies in Taiwan and Hawaii were evaluated for limit of response to various analogues of methyl eugenol. The results are interpreted in terms of the geometry and allosteric requirements of the antennal receptor that triggers the characteristic methyl eugenol reflex. 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.76.4.1561
更新日期:1979-04-01 00:00:00
abstract::MAD2 inhibits the anaphase-promoting complex when chromosomes are unattached to the mitotic spindle. It acts as a tumor suppressor gene because MAD2+/-cells enter anaphase early and display chromosome instability, leading to the formation of lung tumors in mice. Complete MAD2 inactivation has not been identified in 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.0306069101
更新日期:2004-03-30 00:00:00
abstract::Cactus, a Drosophila homologue of I kappa B, binds to and inhibits Dorsal, a homologue of the p50 and p65 components of NF-kappa B. We describe experiments in yeast with various Dorsal and Cactus derivatives showing that Cactus blocks the DNA binding and nuclear localization functions of Dorsal. In contrast, Dorsal'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.92.22.10242
更新日期:1995-10-24 00:00:00
abstract::Characterizing the entropy of a system is a crucial, and often computationally costly, step in understanding its thermodynamics. It plays a key role in the study of phase transitions, pattern formation, protein folding, and more. Current methods for entropy estimation suffer from a high computational cost, lack of gen...
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.2017042117
更新日期:2020-12-01 00:00:00
abstract::A central question in protein-DNA recognition is the origin of the specificity that permits binding to the correct site in the presence of excess, nonspecific DNA. In the P22 Arc repressor, the Phe-10 side chain is part of the hydrophobic core of the free protein but rotates out to pack against the sugar-phosphate bac...
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.96.3.811
更新日期:1999-02-02 00:00:00
abstract::Construction of deletion derivative plasmids and cloning of restriction fragments from plasmids containing the Salmonella typhimurium origin of replication (ori) were used to locate the functional origin to within a DNA fragment of 296 base pairs between the genes uncB and asn. The nucleotide sequence of the S. typhim...
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.77.5.2460
更新日期:1980-05-01 00:00:00
abstract::Whereas amyloid-β (Aβ) accumulates in the brain of normal animals dosed with low levels of copper (Cu), the mechanism is not completely known. Cu could contribute to Aβ accumulation by altering its clearance and/or its production. Because Cu homeostasis is altered in transgenic mice overexpressing Aβ precursor protein...
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.1302212110
更新日期:2013-09-03 00:00:00
abstract::Global biological datasets generated by genomics, transcriptomics, and proteomics provide new approaches to understanding the relationship between the genome and the synapse. Combined transcriptome analysis and multielectrode recordings of neuronal network activity were used in mouse embryonic primary neuronal culture...
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.0609071104
更新日期:2007-03-13 00:00:00
abstract::Cyclic GMP (cGMP) is an important second messenger in eukaryotes. It is formed by guanylyl cyclases (GCs), members of the nucleotidyl cyclases class III, which also comprises adenylyl cyclases (ACs) from most organisms. To date, no structures of eukaryotic GCs are available, and all bacterial class III proteins were 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.0808473105
更新日期:2008-10-14 00:00:00
abstract::Chromosomal RNA, which is a component of the chromosomes of higher organisms, and whose participation is required for sequence-specific interaction of chromosomal proteins with chromosomal DNA, occurs in chromosomes bound to DNA. We have found that the DNA sequences to which chromosomal RNA binds are repetitive ones. ...
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.68.2.387
更新日期:1971-02-01 00:00:00
abstract::We have located a positive, cis-acting DNA sequence element within the 5' flanking DNA of the c-myc gene (-125 base pairs). This DNA sequence element has a large purine-pyrimidine strand asymmetry and can assume the H-DNA conformation. A factor with the properties of a ribonucleoprotein (RNP) interacts with this DNA 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.86.24.9682
更新日期:1989-12-01 00:00:00
abstract::Age-related hearing loss and noise-induced hearing loss are major causes of human morbidity. Here we used genetics and functional studies to show that a shared cause of these disorders may be loss of function of the ATP-gated P2X(2) receptor (ligand-gated ion channel, purinergic receptor 2) that is expressed in sensor...
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.1222285110
更新日期:2013-02-05 00:00:00
abstract::The way general anesthetics cause their clinically useful effects on the nervous system is not known. Since the principal determinant of the potency of these agents is their solubility in oil, the role of chemical structure in affecting anesthetic targets has been obscured. In this work, we use an intense beam of ligh...
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.91.6.2135
更新日期:1994-03-15 00:00:00
abstract::mAbs against tumor-associated carbohydrate antigens have the potential to play a prominent role in cancer immunotherapy. However, it has not been possible to fully exploit the clinical utility of such antibodies primarily, because those of adequate affinity could be derived only from murine sources. To address this pr...
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.96.12.6953
更新日期:1999-06-08 00:00:00
abstract::In previous studies from this laboratory, the binding regions of alpha-neurotoxins on human and Torpedo acetylcholine (AcCho) receptors (AcChoRs) and the binding regions for the receptor on the toxin were characterized with synthetic peptides of the respective molecules. In the present work, peptides representing 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.87.16.6156
更新日期:1990-08-01 00:00:00
abstract::A murine hybridoma-derived antibody (IPH.134) has been produced which has apparent high binding specificity for an extract of Schistosoma japonicum adult worms. No binding was detected to extracts of S. japonicum eggs or to extracts from other adult trematodes (Fasciola hepatica, Paragonimus westermanii, Clonorchis si...
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.78.5.3165
更新日期:1981-05-01 00:00:00
abstract::Rad51 is a highly conserved eukaryotic homolog of the prokaryotic recombination protein RecA, which has been shown to function in both recombinational repair of DNA damage and meiotic recombination in yeast. In primary murine B cells cultured with lipopolysaccharide (LPS) to stimulate heavy chain class switch recombin...
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.93.19.10222
更新日期:1996-09-17 00:00:00