Abstract:
:During CsCl isopycnic centrifugation at 20 mM Mg(++), Escherichia coli 30S ribosomal subunits specifically lose proteins S1, S2, S3, S5, S9, S10, and S14. The resultant 30S core is unable to stimulate the GTPase activity of EF-G in the presence of 50S subunits. Activity could be restored to a small extent by adding back S2, S5, or S9. However, when S5 and S9 were added together, they cooperatively produced 30S particles 1.5 times more active than the original native 30S subunits. The small amount of activity restored by S2 was simply additive to that restored by S5 or S9. None of the other split proteins showed any restoring capability. Ability of the various protein-deficient 30S particles to couple with 50S subunits corresponded closely to their activity in the EF-G GTPase reaction. It is concluded that S5 and S9 together enable the 30S subunit to participate in the formation of a GTPase-active 30S-50S-EF-G complex.
journal_name
Proc Natl Acad Sci U S Aauthors
Marsh RC,Parmeggiani Adoi
10.1073/pnas.70.1.151subject
Has Abstractpub_date
1973-01-01 00:00:00pages
151-5issue
1eissn
0027-8424issn
1091-6490journal_volume
70pub_type
杂志文章abstract::To study the similarity between a putative cloned mammalian release factor (RF) and tryptophanyl-tRNA synthetase (TRS), a recombinant rabbit RF fusion protein was expressed from prokaryotic expression vectors. Purified fractions of the fusion proteins were tested for TRS and RF activities. Addition of the fusion prote...
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.91.7.2777
更新日期:1994-03-29 00:00:00
abstract::Replication of the single-stranded DNA genome of geminiviruses occurs via a double-stranded intermediate that is subsequently used as a template for rolling-circle replication of the viral strand. Only one of the proteins encoded by the virus, here referred to as replication initiator protein (Rep protein), is indispe...
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.92.9.3879
更新日期:1995-04-25 00:00:00
abstract::Global warming is intensifying interest in the mechanisms enabling ectothermic animals to adjust physiological performance and cope with temperature change. Here we show that embryonic temperature can have dramatic and persistent effects on thermal acclimation capacity at multiple levels of biological organization. Ze...
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.1205012109
更新日期:2012-08-28 00:00:00
abstract::After prolonged exposure to ascorbate, collagen synthesis in cultured human skin fibroblasts increased approximately 8-fold with no significant change in synthesis of noncollagen protein. This effect of ascorbate appears to be unrelated to its cofactor function in collagen hydroxylation. The collagenous protein secret...
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.78.5.2879
更新日期:1981-05-01 00:00:00
abstract::The E6 oncoprotein of human papillomaviruses (HPVs) that are associated with cervical cancer utilizes the cellular ubiquitin-protein ligase E6-AP to target the tumor suppressor p53 for degradation. In normal cells (i.e., in the absence of E6), p53 is also a target of the ubiquitin-proteasome pathway. Under these condi...
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.031470698
更新日期:2001-01-30 00:00:00
abstract::Zfp57 is a maternal-zygotic effect gene that maintains genomic imprinting. Here we report that Zfp57 mutants exhibited a variety of cardiac defects including atrial septal defect (ASD), ventricular septal defect (VSD), thin myocardium, and reduced trabeculation. Zfp57 maternal-zygotic mutant embryos displayed more sev...
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.1415541112
更新日期:2015-04-21 00:00:00
abstract::We investigated the operation of a posttranslational protein translocation pathway to determine whether ions are excluded from the translocase during protein transport. The membrane capacitance during protein translocation across chloroplast thylakoid membranes was monitored via electric-field-indicating carotenoid el...
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.95.4.1590
更新日期:1998-02-17 00:00:00
abstract::The with-no-lysine (K) (WNK) kinases are an atypical family of protein kinases that regulate ion transport across cell membranes. Mutations that result in their overexpression cause hypertension-related disorders in humans. Of the four mammalian WNKs, only WNK1 is expressed throughout the body. We report that WNK1 inh...
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.1617649113
更新日期:2016-12-13 00:00:00
abstract::Aire induces ectopic expression of peripheral tissue antigens (PTAs) in thymic medullary epithelial cells, which promotes immunological tolerance. Beginning with a broad screen of histone peptides, we demonstrate that the mechanism by which this single factor controls the transcription of thousands of genes involves 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.0808470105
更新日期:2008-10-14 00:00:00
abstract::Alternative adaptations-different adaptive phenotypes maintained in the same life stage and the same population but not necessarily simultaneously expressed in the same individual-represent contrasting character sets produced by the same genome, in effect allowing a single species to occupy more than one sympatric nic...
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.83.5.1388
更新日期:1986-03-01 00:00:00
abstract::The sudden appearance of calcified skeletons among many different invertebrate taxa at the Precambrian-Cambrian transition may have required minor reorganization of preexisting secretory functions. In particular, features of the skeletal organic matrix responsible for regulating crystal growth by inhibition may be der...
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.93.4.1554
更新日期:1996-02-20 00:00:00
abstract::The uterine epithelium of mice and humans undergoes cyclical waves of cell proliferation and differentiation under the regulation of estradiol-17β (E2) and progesterone (P4). These epithelial cells respond to E2 with increased protein and DNA synthesis, whereas P4 inhibits only the E2-induced DNA synthetic response. 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.1418973112
更新日期:2015-03-17 00:00:00
abstract::Activins and inhibins, members of the type beta transforming growth factor superfamily of growth regulatory proteins, are produced in multiple tissues and affect diverse physiologic processes. Using embryonic stem cell technology, we previously demonstrated that inhibin can function as a gonadal tumor suppressor. In 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.91.19.8817
更新日期:1994-09-13 00:00:00
abstract::Cystic fibrosis (CF) is a recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The most common symptoms include progressive lung disease and chronic digestive conditions. CF is the first human genetic disease to benefit from having five different species of animal models. De...
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.1913127117
更新日期:2020-05-12 00:00:00
abstract::Treatment with neuraminidase (NA) plus galactose oxidase (GalOxase) does not cause stimulation of human thymocytes. However, stimulation can be achieved by addition of exogenous interleukin 2 (IL-2). The IL-2-induced stimulation was inhibited with anti-Tac antibody, indicating that NA/GalOxase-oxidized cells can serve...
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.81.16.5209
更新日期:1984-08-01 00:00:00
abstract::We analyzed the distribution of the cauliflower mosaic virus (CaMV) aphid transmission factor (ATF), produced via a baculovirus recombinant, within Sf9 insect cells. Immunogold labeling revealed that the ATF colocalizes with an atypical cytoskeletal network. Detailed observation by electron microscopy demonstrated tha...
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.93.26.15158
更新日期:1996-12-24 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::Documented cases of convergent molecular evolution due to selection are fairly unusual, and examples to date have involved only a few amino acid positions. However, because convergence mimics shared ancestry and is not accommodated by current phylogenetic methods, it can strongly mislead phylogenetic inference when it...
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.0900233106
更新日期:2009-06-02 00:00:00
abstract::Human mammary epithelial cells secrete and express on their cell surfaces complex mucin glycoproteins (Mr greater than 250,000) that are developmentally regulated, tumor-associated, and highly immunogenic. Studies using monoclonal antibodies directed to these glycoproteins suggest that their molecular structures can v...
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.84.17.6060
更新日期:1987-09-01 00:00:00
abstract::I describe the self-splicing of an RNA that consists of exon sequences flanked by group II intron sequences. I find that this RNA undergoes accurate splicing in vitro, yielding an excised exon circle. This splicing reaction involves the joining of the 5' splice site at the end of an exon to the 3' splice site at the 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.90.18.8624
更新日期:1993-09-15 00:00:00
abstract::Among the variety of specialized intercellular junctions, those of the adherens type have the most obvious association with cytoskeletal elements. This may be with the actin microfilament system as in the zonula adherens or with intermediate filaments as in the macula adherens, or desmosome. In the former case, it is ...
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.88.11.4796
更新日期:1991-06-01 00:00:00
abstract::We have determined the general constraints that govern sequence divergence in proteins that retain entirely, or very largely, the same structure and function. To do this we collected data from three different groups of orthologous sequences: those found in humans and mice, in humans and chickens, and in Escherichia 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.0703737104
更新日期:2007-06-12 00:00:00
abstract::Animals capable of regenerating multiple tissue types, organs, and appendages after injury are common yet sporadic and include some sponge, hydra, planarian, and salamander (i.e., newt and axolotl) species, but notably such regenerative capacity is rare in mammals. The adult MRL mouse strain is a rare exception 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.1000830107
更新日期:2010-03-30 00:00:00
abstract::CD4(+) T cells producing IL-17 [T helper (Th)17], as distinct from Th1 or Th2 cells, have recently been shown to be associated with autoimmunity, but it is not entirely clear how Th17 cells are generated from naïve T cells. We demonstrate here that IL-6, but not TNF-alpha or IL-1beta, can, in combination with TGF-beta...
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.0705268104
更新日期:2007-07-17 00:00:00
abstract::Chlorpromazine (3 x 10(-4)M) prevents the stimulation of adenyl cyclase activity in thyroid membranes produced by thyrotropin and prostaglandin, ACTH stimulation of adenyl cyclase in adrenal tissue, and glucagon- and epinephrine-stimulation of adenyl cyclase activity in liver. Baseline activity is unaffected. Parathyr...
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.65.2.454
更新日期:1970-02-01 00:00:00
abstract::A model chemical network involving reactions and diffusion is studied. Spatially and temporally ordered solutions of the equations are found by bifurcation theory. These solutions are calculated analytically and their stability is studied. Properties of these dissipative structures are discussed, and a comparison with...
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.71.7.2748
更新日期:1974-07-01 00:00:00
abstract::The crystal structure of a recombinant alphaEC domain from human fibrinogen-420 has been determined at a resolution of 2.1 A. The protein, which corresponds to the carboxyl domain of the alphaE chain, was expressed in and purified from Pichia pastoris cells. Felicitously, during crystallization an amino-terminal segme...
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.95.16.9099
更新日期:1998-08-04 00:00:00
abstract::Ethionamide (ETA) is an important component of second-line therapy for the treatment of multidrug-resistant tuberculosis. Synthesis of radiolabeled ETA and an examination of drug metabolites formed by whole cells of Mycobacterium tuberculosis (MTb) have allowed us to demonstrate that ETA is activated by S-oxidation 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.97.17.9677
更新日期:2000-08-15 00:00:00
abstract::Superresolution fluorescence microscopy overcomes the diffraction resolution barrier and allows the molecular intricacies of life to be revealed with greatly enhanced detail. However, many current superresolution techniques still face limitations and their implementation is typically associated with a steep learning c...
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.1204917109
更新日期:2012-07-03 00:00:00
abstract::The dnaX gene (previously called dnaZX) of Escherichia coli has only one open reading frame for a 71-kDa polypeptide from which two distinct DNA polymerase III holoenzyme subunits, tau (71 kDa) and gamma (47 kDa), are produced. To determine how the gamma subunit is generated, we examined the influence of mutations in ...
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.87.7.2516
更新日期:1990-04-01 00:00:00