Abstract:
:Leucine analogs were tested in the Krebs II ascites cell-free translation system for the ability to inhibit preprotein cleavage by replacing leucine in nascent chains of bovine preprolactin, rat preprolactin, human placental prelactogen (pre-hPL), and pre-alpha subunit of human chorionic gonadotropin (alpha-hCG). In the absence of analog, ascites microsomal membranes cleaved these preproteins to their mature forms and sequestered the processed products. Also, two asparagine residues in alpha-hCG were glycosylated. When 4 mM beta-DL-hydroxyleucine was added to the lysate instead of L-leucine, cotranslational processing and sequestration of both species of preprolactin and pre-hPL were inhibited. Sequential Edman degradation confirmed that pre-hPL was not cleaved. The inhibition of processing by beta-hydroxyleucine resulted from its incorporation into protein. This was shown by reversal of the effect by addition of leucine and by inhibition of [(3)H]leucine incorporation into protein. Of significance, the processing of pre-alpha-hCG was less sensitive to beta-hydroxyleucine because its prepeptide contains only four scattered leucine residues, whereas the presegments of hPL and the prolactins contain six to eight clustered leucine residues. These experiments demonstrate that translocation and processing of secretory proteins require structural features determined by the primary amino acid sequence.
journal_name
Proc Natl Acad Sci U S Aauthors
Hortin G,Boime Idoi
10.1073/pnas.77.3.1356subject
Has Abstractpub_date
1980-03-01 00:00:00pages
1356-60issue
3eissn
0027-8424issn
1091-6490journal_volume
77pub_type
杂志文章abstract::We describe here a third region of variability in human fibronectin (FN) due to alternative RNA splicing. Two other positions of alternative splicing have been reported previously (ED and IIICS). The third region involves a 273-nucleotide exon encoding exactly one 91-amino acid repeat of type III homology, located bet...
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.84.20.7179
更新日期:1987-10-01 00:00:00
abstract::The perforant path (PP) undergoes synaptic changes in the course of aging and dementia. Previous studies attempting to assess the integrity of the PP in humans using diffusion tensor imaging (DTI) were limited by low resolution and the inability to identify PP fibers specifically. Here we present an application of DTI...
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.1002113107
更新日期:2010-07-13 00:00:00
abstract::Members of the CCAAT-binding transcription factor (CTF) family of proteins stimulate the initiation of adenovirus DNA replication and act as transcriptional activators. To investigate the mechanisms underlying CTF-mediated transactivation patterns, we expressed several natural CTF variants in Saccharomyces cerevisiae ...
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.91.9.3901
更新日期:1994-04-26 00:00:00
abstract::The binding protein for the K+-channel toxin dendrotoxin I was purified from a detergent extract of rat brain membranes. The purification procedure utilized chromatography on DEAE-Trisacryl, affinity chromatography on a dendrotoxin-I-Aca 22 column, and wheat germ agglutinin-Affigel 10 with a final 3800- to 4600-fold e...
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.85.13.4919
更新日期:1988-07-01 00:00:00
abstract::The epidermal growth factor receptor gene has been found to be amplified and rearranged in human glioblastomas in vivo. Here we present the sequence across a splice junction of aberrant epidermal growth factor receptor transcripts derived from corresponding and uniquely rearranged genes that are coamplified and coexpr...
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.87.21.8602
更新日期:1990-11-01 00:00:00
abstract::What are the forces that shape the structure of prokaryotic genomes: the order of genes, their proximity, and their orientation? Coregulation and coordinated horizontal gene transfer are believed to promote the proximity of functionally related genes and the formation of operons. However, forces that influence the str...
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.0700672104
更新日期:2007-08-28 00:00:00
abstract::This study presents, to our knowledge, the first on-line measurement of acetylcholinesterase (AcChoEase) release from brain tissue. It is now well established that a soluble form of the enzyme is released from central nervous system neurons, and it has been proposed on indirect grounds that such release may occur not ...
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.84.9.3047
更新日期:1987-05-01 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::Striking taste disturbances are reported in cancer patients treated with Hedgehog (HH)-pathway inhibitor drugs, including sonidegib (LDE225), which block the HH pathway effector Smoothened (SMO). We tested the potential for molecular, cellular, and functional recovery in mice from the severe disruption of taste-organ ...
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.1712881114
更新日期:2017-11-28 00:00:00
abstract::Parathyroid hormone (PTH) is central to calcium homeostasis and bone maintenance in vertebrates, and as such it has been used for treating osteoporosis. It acts primarily by binding to its receptor, PTH1R, a member of the class B G protein-coupled receptor (GPCR) family that also includes receptors for glucagon, calci...
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.0801027105
更新日期:2008-04-01 00:00:00
abstract::Guinea pigs were immunized with liposomal model membranes containing phosphatidylethanolamine (PE) or glycerophosphorylethanolamine (GPE) derivatives in which the amino function was substituted with either dinitrophenylaminocaproyl (Dnp-Cap) or mono(p-azobenzenearsonic acid)tyrosyl (ABA-Tyr) residues. Previous studies...
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.72.11.4582
更新日期:1975-11-01 00:00:00
abstract::Extracts of insect cells infected with baculoviruses recombinant for the herpes simplex virus 1 (HSV-1)-encoded enzymes that are required for its replication can promote the rolling circle replication of circular plasmid templates. Replication is independent of a HSV-1 origin of replication (oris) or the HSV-1 origin ...
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.91.22.10665
更新日期:1994-10-25 00:00:00
abstract::Transforming growth factor beta (TGF-beta) causes growth arrest in most cell types. TGF-beta induces hypophosphorylation of retinoblastoma susceptibility gene 1 product (RB), which sequesters E2F factors needed for progression into S phase of the cell cycle, thereby leading to cell cycle arrest at G1. It is possible, ...
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.94.10.4948
更新日期:1997-05-13 00:00:00
abstract::An implicit assumption of speciation biology is that population differentiation is an important stage of evolutionary diversification, but its significance as a rate-limiting control on phylogenetic speciation dynamics remains largely untested. If population differentiation within a species is related to its speciatio...
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.1617397114
更新日期:2017-06-13 00:00:00
abstract::A central tenet in understanding the biological effects of ionizing radiation has been that the initially affected cells were directly damaged by the radiation. By contrast, evidence has emerged concerning "bystander" responses involving damage to nearby cells that were not themselves directly traversed by the radiati...
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.0505020102
更新日期:2005-10-04 00:00:00
abstract::Selenophosphate, an activated form of selenium that can serve as a selenium donor, is generated by the selD gene product, selenophosphate synthetase (SPS). Selenophosphate is required by several bacteria and by mammals for the specific synthesis of Secys-tRNA, the precursor of selenocysteine in selenoenzymes. Although...
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.0409042102
更新日期:2005-01-25 00:00:00
abstract::The strong consistency of least squares estimates in multiple regression models with independent errors is obtained under minimal assumptions on the design and weak moment conditions on the errors. ...
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.75.7.3034
更新日期:1978-07-01 00:00:00
abstract::Two human 12-lipoxygenase enzyme (arachidonate:oxygen 12-oxidoreductase, EC 1.13.11.31)-related genes were characterized from 13 distinct clones isolated from three genomic bacteriophage and cosmid libraries. A complete gene (12-lipoxygenase gene 1) spanning approximately 17 kilobases and consisting of 14 exons with 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.89.9.3962
更新日期:1992-05-01 00:00:00
abstract::A sensitive test for kinetic unfolding intermediates in ribonuclease A (EC 3.1.27.5) is performed under conditions where the enzyme unfolds slowly (10 degrees C, pH 8.0, 4.5 M guanidinium chloride). Exchange of peptide NH protons (2H-1H) is used to monitor structural opening of individual hydrogen bonds during unfoldi...
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.92.7.2657
更新日期:1995-03-28 00:00:00
abstract::We investigate the roles of the pseudospin and the valley degeneracy in electron scattering at graphene edges. It is found that they are strongly correlated with charge density modulations of short-wavelength oscillations and slowly decaying beat patterns in the electronic density profile. Theoretical analyses using 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.1114548108
更新日期:2011-11-15 00:00:00
abstract::The livers of insulin-resistant, diabetic mice manifest selective insulin resistance, suggesting a bifurcation in the insulin signaling pathway: Insulin loses its ability to block glucose production (i.e., it fails to suppress PEPCK and other genes of gluconeogenesis), yet it retains its ability to stimulate fatty aci...
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.0914798107
更新日期:2010-02-23 00:00:00
abstract::One of the serious limitations of tokamaks as reactors is the occurrence of disruptions. Stellarators designed by advanced computational methods provide an attractive alternative for a major experiment in magnetic fusion research. Configurations with approximate two-dimensional magnetic symmetry have been found with h...
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.97.3.972
更新日期:2000-02-01 00:00:00
abstract::Chronic, low grade, sterile inflammation frequently accompanies aging and age-related diseases. Cellular senescence is associated with the production of proinflammatory chemokines, cytokines, and extracellular matrix (ECM) remodeling proteases, which comprise the senescence-associated secretory phenotype (SASP). We fo...
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.1515386112
更新日期:2015-11-17 00:00:00
abstract::Dengue virus (DENV) is the most prevalent human vector-borne viral disease. The force of infection (FoI), the rate at which susceptible individuals are infected in a population, is an important metric for infectious disease modeling. Understanding how and why the FoI of DENV changes over time is critical for developin...
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.1809253115
更新日期:2018-10-16 00:00:00
abstract::Cellular differentiation leading to formation of the bradyzoite tissue cyst stage is the underlying cause of chronic toxoplasmosis. Consequently, mechanisms responsible for controlling development in the Toxoplasma intermediate life cycle have long been sought. Here, we identified 15 Toxoplasma mRNAs induced in early ...
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.1300059110
更新日期:2013-04-23 00:00:00
abstract::The mechanism of preferential transmission (i.e., maternal inheritance) of cytoplasmic genes was investigated with chloroplast DNA of Chlamydomonas as a model system. The behavior of nuclear and chloroplast DNAs were compared in the sexual cycle; DNAs from male and female parents were distinguished by labeling with (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.69.9.2410
更新日期:1972-09-01 00:00:00
abstract::Biologically active (125)I-labeled bovine parathyroid hormone (prepared by electrolytic iodination) and its synthetic NH(2)-terminal (1-34) biologically active fragment bound rapidly and specifically to a purified plasma membrane preparation from bovine renal cortex. Binding of labeled intact hormone or labeled NH(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.71.3.723
更新日期:1974-03-01 00:00:00
abstract::The development of anther and pollen is important for male reproduction, and this process is coordinately regulated by many external and internal cues. In this study, we systematically examined the male reproductive phenotypes of a series of brassinosteroid biosynthetic and signaling mutants and found that, besides 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.0912333107
更新日期:2010-03-30 00:00:00
abstract::Leukocyte adherence to endothelium is in part mediated by the transient expression of endothelial-leukocyte adhesion molecule 1 (ELAM-1) on endothelial surfaces stimulated by tumor necrosis factor alpha (TNF), interleukin (IL) 1, or bacterial lipopolysaccharide (LPS). The intracellular factors controlling induction 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.88.15.6523
更新日期:1991-08-01 00:00:00
abstract::The neural pathway that governs an escape response of Drosophila to sudden changes in light intensity can be artificially induced by electrical stimulation of the brain and monitored by electrical recording from the effector muscles. We have refined previous work in this system to permit reliable ascertainment of two ...
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.93.19.10446
更新日期:1996-09-17 00:00:00