Abstract:
:Ultraviolet irradiation of the [3H]colchicine-tubulin complex leads to direct photolabeling of tubulin with low but practicable efficiency. The bulk (70% to greater than 90%) of the labeling occurs on beta-tubulin and appears early after irradiation, whereas alpha-tubulin is labeled later. The labeling ratio of beta-tubulin to alpha-tubulin (beta/alpha ratio) is reduced by prolonged incubation, prolonged irradiation, urea, high ionic strength, the use of aged tubulin, dilution of tubulin, or large concentrations of colchicine or podophyllotoxin. Glycerol increases the beta/alpha ratio. Limited data with [3H]podophyllotoxin show that it covalently bound with a similar beta/alpha distribution. Vinblastine, on the other hand, exhibits preferential attachment to alpha-tubulin. The possibilities that colchicine binds at the interface between alpha-tubulin and beta-tubulin, that the drug spans this interface, and that both subunits may contribute to the binding site are suggested.
journal_name
Proc Natl Acad Sci U S Aauthors
Wolff J,Knipling L,Cahnmann HJ,Palumbo Gdoi
10.1073/pnas.88.7.2820subject
Has Abstractpub_date
1991-04-01 00:00:00pages
2820-4issue
7eissn
0027-8424issn
1091-6490journal_volume
88pub_type
杂志文章abstract::Profilin2 (PFN2) is a target of the embryonic stem cell (ESC)-enriched miR-290 family of microRNAs (miRNAs) and an actin/dynamin-binding protein implicated in endocytosis. Here we show that the miR-290-PFN2 pathway regulates many aspects of ESC biology. In the absence of miRNAs, PFN2 is up-regulated in ESCs, with a re...
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.2002750117
更新日期:2020-08-25 00:00:00
abstract::We developed two solid-phase reagent systems for microscopic visualization and characterization of melanocyte-stimulating hormone (MSH) receptors of melanoma cells. Multiple copies of [Nle-4,D-Phe-7]-alpha-MSH, a potent analog of alpha-MSH, were conjugated to microspheres (latex beads) or macrospheres (polyamide beads...
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.93.24.13715
更新日期:1996-11-26 00:00:00
abstract::Triglyceridemic response to a standard oral fat meal was determined in 28 healthy subjects and related to the levels of several lipids, lipoproteins, and apolipoproteins in the post-absorptive plasma. A fatty test meal was administered orally, and postprandial plasma triglyceride levels were determined. In the fasting...
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.80.5.1449
更新日期:1983-03-01 00:00:00
abstract::The human papillomavirus E7 protein is phosphorylated at the two serines in positions 31/32, which are part of a consensus sequence for casein kinase II (CKII). In this study, we have investigated the effect of CKII phosphorylation site mutations, all of which lead to unphosphorylated E7 proteins. The replacement of 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.88.12.5187
更新日期:1991-06-15 00:00:00
abstract::A revelation of the genomic age has been the contributions of the mobile DNA segments called transposable elements to chromosome structure, function, and evolution in virtually all organisms. Substantial fractions of vertebrate genomes derive from transposable elements, being dominated by retroelements that move via 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.1217548110
更新日期:2013-01-02 00:00:00
abstract::RelB is an NF-κB family transcription factor activated in the noncanonical pathway downstream of NF-κB-inducing kinase (NIK) and TNF receptor family members including lymphotoxin-β receptor (LTβR) and CD40. Early analysis suggested that RelB is required for classical dendritic cell (cDC) development based on a severe ...
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.1619863114
更新日期:2017-04-11 00:00:00
abstract::The human immunodeficiency virus 1 (HIV-1) long terminal repeat (LTR) sequences were inserted into adenovirus in place of the E1 region. The HIV-1 LTR contained in this recombinant adenovirus responds to trans-activation by tatIII in a HeLa cell line constitutively expressing that HIV-1 gene product. In addition, 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.85.12.4200
更新日期:1988-06-01 00:00:00
abstract::The tau and gamma subunits of DNA polymerase III holoenzyme are both products of the dnaX gene. Since tau and gamma are required as stoichiometric components of the replicative complex, a mechanism must exist for the cell to coordinate their synthesis and ensure that both subunits are present in an adequate quantity 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.87.10.3713
更新日期:1990-05-01 00:00:00
abstract::The transcription factor SRY (sex-determining region)-box 2 (SOX2) is an important functional marker of neural precursor cells (NPCs) and plays a critical role in self-renewal and neuronal differentiation; however, the molecular mechanisms underlying its functions are poorly understood. Using human embryonic stem cell...
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.1220176110
更新日期:2013-08-06 00:00:00
abstract::Regulatory T cells (Tregs) are key modulators of immune tolerance, capable of suppressing inflammatory immune responses and promoting nonlymphoid tissue homeostasis. Helios, a transcription factor (TF) that is selectively expressed by Tregs, has been shown to be essential for the maintenance of Treg lineage stability ...
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.1720447115
更新日期:2018-02-27 00:00:00
abstract::ApcMin (Min, multiple intestinal neoplasia) is a point mutation in the murine homolog of the APC gene. Min/+ mice develop multiple intestinal adenomas, as do humans carrying germ-line mutations in APC. Female mice carrying Min are also prone to develop mammary tumors. Min/+ mammary glands are more sensitive to chemica...
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.90.19.8977
更新日期:1993-10-01 00:00:00
abstract::Breakage-fusion-bridge (BFB) is a mechanism of genomic instability characterized by the joining and subsequent tearing apart of sister chromatids. When this process is repeated during multiple rounds of cell division, it leads to patterns of copy number increases of chromosomal segments as well as fold-back inversions...
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.1220977110
更新日期:2013-04-02 00:00:00
abstract::The ganglioside pattern of both SV40- and polyoma virus-transformed mouse cell lines differs from that of the parent cell lines or of cell lines that have transformed spontaneously in tissue culture. This is manifested by a dramatic decrease of gangliosides with an oligosaccharide chain larger than sialyllactose. Pres...
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.67.2.757
更新日期:1970-10-01 00:00:00
abstract::Dust grains of organic matter were the main reservoir of C and N in the forming Solar System and are thus considered to be an essential ingredient for the emergence of life. However, the physical environment and the chemical mechanisms at the origin of these organic grains are still highly debated. In this study, we 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.1808101115
更新日期:2018-08-21 00:00:00
abstract::Among the 15 extracellular domains of the mannose 6-phosphate/insulin-like growth factor-2 receptor (M6P/IGF2R), domain 11 has evolved a binding site for IGF2 to negatively regulate ligand bioavailability and mammalian growth. Despite the highly evolved structural loops of the IGF2:domain 11 binding site, affinity-enh...
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.1513023113
更新日期:2016-05-17 00:00:00
abstract::The Schiff base adducts of glyceraldehyde with hemoglobin undergo Amadori rearrangement to form stable ketoamine structures; this reaction is similar to the nonenzymic glucosylation of proteins. In the present studies the analogous rearrangement of the Schiff base adducts of glycolaldehyde with proteins has been demon...
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.80.12.3590
更新日期:1983-06-01 00:00:00
abstract::Flagellin and several other external components of the bacterial flagellum are thought to be exported, not by the general N-terminal signal peptide-dependent pathway, but by a flagellum-specific pathway involving a central channel in the flagellum itself. We have constructed a variety of mutant alleles of the Escheric...
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.86.13.4953
更新日期:1989-07-01 00:00:00
abstract::A synthetic DNA based on the known amino acid sequence of the brain/gut peptide cholecystokinin (CCK) was synthesized. This DNA contained deoxyinosines at ambiguous codon positions and was used as a probe to isolate the CCK gene directly from a human genomic library. Nucleotide sequence analysis of the isolated gene 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.82.7.1931
更新日期:1985-04-01 00:00:00
abstract::Our ability to interpret seismic observations including the seismic discontinuities and the density and velocity profiles in the earth's interior is critically dependent on the accuracy of pressure measurements up to 364 GPa at high temperature. Pressure scales based on the reduced shock-wave equations of state alone ...
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.0609013104
更新日期:2007-05-29 00:00:00
abstract::Telomerase is a special reverse transcriptase that extends one strand of the telomere repeat by using a template embedded in an RNA subunit. Like other polymerases, telomerase is believed to use a pair of divalent metal ions (coordinated by a triad of aspartic acid residues) for catalyzing nucleotide addition. Here we...
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.0502252102
更新日期:2005-07-12 00:00:00
abstract::For brain functions such as working memory and motor planning, neuronal circuits are able to sustain persistent activity after transient inputs. Theoretical studies have suggested that persistent activity can exist in recurrently connected networks as active reverberation. However, the actual cellular processes underl...
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.0500717102
更新日期:2005-07-19 00:00:00
abstract::T-cell-derived soluble factors that inhibit both X4 and R5 HIV are recognized as important in controlling HIV. Whereas three β chemokines, regulated-on-activation normal T-cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1α, and MIP-1β, account for the suppression of R5 HIV by blockade of 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.1202240109
更新日期:2012-04-03 00:00:00
abstract::The synaptonemal complex (SC) is a conserved meiotic structure that regulates the repair of double-strand breaks (DSBs) into crossovers or gene conversions. The removal of any central-region SC component, such as the Drosophila melanogaster transverse filament protein C(3)G, causes a complete loss of SC structure 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.1910840116
更新日期:2019-10-22 00:00:00
abstract::Prions are thought to replicate in an autocatalytic process that converts cellular prion protein (PrP(C)) to the disease-associated misfolded PrP isoform (PrP(Sc)). Our study scrutinizes this hypothesis by in vitro protein misfolding cyclic amplification (PMCA). In serial transmission PMCA experiments, PrP(Sc) was ino...
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.0404650101
更新日期:2004-08-17 00:00:00
abstract::Plant phylogenetic estimates are most likely to be reliable when congruent evidence is obtained independently from the mitochondrial, plastid, and nuclear genomes with all methods of analysis. Here, results are presented from separate and combined genomic analyses of new and previously published data, including six an...
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.220427497
更新日期:2000-11-21 00:00:00
abstract::The Met mutant of Drosophila melanogaster is highly resistant to juvenile hormone III (JH III) or its chemical analog, methoprene, an insect growth regulator. Five major mechanisms of insecticide resistance were examined in Met and susceptible Met+ flies. These two strains showed only minor differences when penetratio...
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.87.6.2072
更新日期:1990-03-01 00:00:00
abstract::Naked mole-rats form eusocial colonies consisting of a single breeding female (the queen), several breeding males, and sexually immature adults (subordinates). Subordinates are cooperative and provide alloparental care by huddling and retrieving pups to the nest. However, the physiological mechanism(s) underlying allo...
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.1720530115
更新日期:2018-09-11 00:00:00
abstract::The role of spliced leader RNA (SL RNA) in trans-splicing in Caenorhabditis elegans has been studied through a combination of in vitro mutagenesis and in vivo complementation of rrs-1 mutant nematodes, which lack endogenous SL1 RNA. Three classes of mutant SL1 RNAs have been found-those that rescue the lethal phenotyp...
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.95.8.4235
更新日期:1998-04-14 00:00:00
abstract::Recent data indicate that sustained elevations in plasma insulin suppress the mRNA for IRS-2, a component of the insulin signaling pathway in liver, and that this deficiency contributes to hepatic insulin resistance and inappropriate gluconeogenesis. Here, we use nuclear run-on assays to show that insulin inhibits tra...
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.071054598
更新日期:2001-03-27 00:00:00
abstract::Src tyrosine kinase has long been implicated in colon cancer but much remains to be learned about its substrates. The nuclear receptor hepatocyte nuclear factor 4α (HNF4α) has just recently been implicated in colon cancer but its role is poorly defined. Here we show that c-Src phosphorylates human HNF4α on three tyros...
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.1106799109
更新日期:2012-02-14 00:00:00