Abstract:
:Parasponia, a woody member of the elm family, is the only nonlegume genus whose members are known to form an effective nitrogen-fixing symbiosis with a Rhizobium species. The bacterial strain RP501 is a slow-growing strain of Rhizobium isolated from Parasponia nodules. Strain RP501 also nodulates the legumes siratro (Macroptilium atropurpureum) and cowpea (Vigna unguiculata). Using a cosmid clone bank of RP501 DNA, we isolated a 13.4-kilobase (kb) EcoRI fragment that complemented insertion and point mutations in three contiguous nodulation genes (nodABC) of Rhizobium meliloti, the endosymbiont of alfalfa (Medicago sativa). The complemented R. meliloti nod mutants induced effective nitrogen-fixing nodules on alfalfa seedlings but not on siratro, cowpeas, or Parasponia. The cloned RP501 nodulation locus hybridized to DNA fragments carrying the R. meliloti nodABC genes. A 3-kb cluster of Tn5 insertion mutations on the RP501 13.4-kb EcoRI fragment prevented complementation of R. meliloti nodABC mutations.
journal_name
Proc Natl Acad Sci U S Aauthors
Marvel DJ,Kuldau G,Hirsch A,Richards E,Torrey JG,Ausubel FMdoi
10.1073/pnas.82.17.5841subject
Has Abstractpub_date
1985-09-01 00:00:00pages
5841-5issue
17eissn
0027-8424issn
1091-6490journal_volume
82pub_type
杂志文章abstract::Retinoblastoma-related (RBR) proteins regulate cell division in higher eukaryotes by controlling the adenovirus E2 promoter binding factor (E2F)/dimerization partner (DP) family of transcription factors that regulate expression of many genes involved in cell-cycle progression. We identified a previously undescribed me...
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.0506160102
更新日期:2005-09-13 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::Tidal deltas are characterized by a dendritic network of distributaries that transport water and sediments to the ocean. Here, I show that the distributaries self-organize to uniformly redistribute the tidal prism across the entire delta system. The 2 opposite mechanisms of channel formation by avulsion and channel ab...
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.0806668105
更新日期:2008-12-02 00:00:00
abstract::It has been controversial whether the cytochrome oxidase (CO)-dense blobs in primate primary visual cortex (V1) and CO-dense thin stripes in visual area 2 (V2) are parts of a cortical color-processing stream that is segregated from other functional streams. One of the key pieces of evidence for the segregated color st...
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.0402052101
更新日期:2004-05-04 00:00:00
abstract::A molecular genetic approach employing polymorphic DNA markers has been used to investigate the role of chromosomal aberrations in meningioma, one of the most common tumors of the human nervous system. Comparison of the alleles detected by DNA markers in tumor DNA versus DNA from normal tissue revealed chromosomal alt...
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.84.15.5419
更新日期:1987-08-01 00:00:00
abstract::Residents in the marine intertidal, the zone where terrestrial and marine habitats converge, inhabit an environment that is subject to both the 24-h day and night daily rhythm of the terrestrial earth and also the 12.4-h ebb and flow of the tidal cycle. Here, we investigate the relative contribution of the daily and 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.1111076108
更新日期:2011-09-20 00:00:00
abstract::Two cDNAs encoding two human receptors for retinoic acid (RA), RAR-alpha and RAR-beta, have been characterized recently. Synthetic peptides corresponding to the cDNA-deduced amino acid sequences unique to RAR-alpha and RAR-beta were used to generate anti-RAR-alpha antiserum (SP171) and anti-RAR-beta antisera (SP172 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.86.9.3089
更新日期:1989-05-01 00:00:00
abstract::In the budding yeast Saccharomyces cerevisiae, self-recognition and the thereby promoted aggregation of thousands of cells into protective flocs is mediated by a family of cell-surface adhesins, the flocculins (Flo). Based on this social behavior FLO genes fulfill the definition of "greenbeard" genes, which direct coo...
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.1013210108
更新日期:2010-12-28 00:00:00
abstract::A method has been developed that enables us to identify intracellular degradation intermediates of fructose-bisphosphate aldolase B (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13). This method is based on the use of antibody against thoroughly denatured purified aldolase. This antibody ha...
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.82.18.6114
更新日期:1985-09-01 00:00:00
abstract::Signaling pathways regulating proliferation, differentiation, and apoptosis are commonly mediated through protein-protein interactions as well as reversible phosphorylation of proteins. To facilitate the study of regulated protein-protein interactions in cells and living animals, we optimized firefly luciferase protei...
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.0404041101
更新日期:2004-08-17 00:00:00
abstract::Methane emissions due to accidents in the oil and natural gas sector are very challenging to monitor, and hence are seldom considered in emission inventories and reporting. One of the main reasons is the lack of measurements during such events. Here we report the detection of large methane emissions from a gas well bl...
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.1908712116
更新日期:2019-12-16 00:00:00
abstract::The highly homologous Rnf2 (Ring1b) and Ring1 (Ring1a) proteins were identified as in vivo interactors of the Polycomb Group (PcG) protein Bmi1. Functional ablation of Rnf2 results in gastrulation arrest, in contrast to relatively mild phenotypes in most other PcG gene null mutants belonging to the same functional gro...
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.0434312100
更新日期:2003-03-04 00:00:00
abstract::Prader-Willi syndrome (PWS) and Angelman syndrome (AS) result from the loss of function of imprinted genes in human chromosome 15q11-q13. The central part of mouse chromosome 7 is homologous to human 15q11-q13, with conservation of both gene order and imprinted features. We report here the characterization of a transg...
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.96.16.9258
更新日期:1999-08-03 00:00:00
abstract::Skin wound infections are a significant health problem, and antibiotic resistance is on the rise. Mast cells (MCs) have been shown to contribute to host-defense responses in certain bacterial infections, but their role in skin wound superinfection is unknown. We subjected 2 MC-deficient mouse strains to Pseudomonas ae...
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.1908816116
更新日期:2019-10-08 00:00:00
abstract::Whole-chromosome copy number alterations, also known as aneuploidy, are associated with adverse consequences in most cells and organisms. However, high frequencies of aneuploidy have been reported to occur naturally in the mammalian liver and brain, fueling speculation that aneuploidy provides a selective advantage 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.1415287111
更新日期:2014-09-16 00:00:00
abstract::Inactivation of the retinoblastoma gene (RB gene) is associated with the development of several human malignancies including retinoblastomas, some osteo- and soft tissue sarcomas, small cell lung cancer, and possibly breast and bladder cancers. To our knowledge, this gene has not been evaluated in human germ-cell mali...
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.88.15.6662
更新日期:1991-08-01 00:00:00
abstract::The inhibitory protein that binds calmodulin and thus prevents activation of several Ca2+-dependent enzymes by calmodulin is shown to also bind four Ca2+ per mol of protein with high affinity (Kd less than or equal to 10(-6) M). On the basis of its Ca2+- binding properties and its localization to nervous tissue, the 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.76.12.6270
更新日期:1979-12-01 00:00:00
abstract::Control of transcription and enzyme activities are two interwoven regulatory systems essential for the function of a metabolic node. Saccharomyces cerevisiae strains differing in enzyme activities at the chorismate branch point of aromatic amino acid biosynthesis were constructed by recombinant DNA technology. Express...
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.240469697
更新日期:2000-12-05 00:00:00
abstract::Structural differences between dynein and kinesin suggest a unique molecular mechanism of dynein motility. Measuring the mechanical properties of a single molecule of dynein is crucial for revealing the mechanisms underlying its movement. We measured the step size and force produced by single molecules of active cytop...
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.0508511103
更新日期:2006-04-11 00:00:00
abstract::Nonspatial theory on pathogen evolution generally predicts selection for maximal number of secondary infections, constrained only by supposed physiological trade-offs between pathogen infectiousness and virulence. Spread of diseases in human populations can, however, exhibit large scale patterns, underlining the need ...
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.0405682101
更新日期:2004-12-28 00:00:00
abstract::Real-life decisions are often repeated. Whether considering taking a job in a new city, or doing something mundane like checking if the stove is off, decisions are frequently revisited even if no new information is available. This mode of behavior takes a particularly pathological form in obsessive-compulsive disorder...
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.2014271117
更新日期:2021-01-05 00:00:00
abstract::The primate visual motion system performs numerous functions essential for survival in a dynamic visual world. Prominent among these functions is the ability to recover and represent the trajectories of objects in a form that facilitates behavioral responses to those movements. The first step toward this goal, which c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.92.7.2433
更新日期:1995-03-28 00:00:00
abstract::Proopiomelanocortin (POMC), a major pituitary product, is also present in the adult mouse testis. We have shown previously that POMC mRNAs are most abundant in a subpopulation of Leydig cells associated with tubules in specific stages of the cycle of the seminiferous epithelium. In the present study, we examined the 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.84.6.1600
更新日期:1987-03-01 00:00:00
abstract::Although it has long been recognized that the enteric community of bacteria that inhabit the human distal intestinal track broadly impacts human health, the biochemical details that underlie these effects remain largely undefined. Here, we report a broad MS-based metabolomics study that demonstrates a surprisingly lar...
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.0812874106
更新日期:2009-03-10 00:00:00
abstract::Environmental stress often leads to an increased production of reactive oxygen species that are involved in plastid-to-nucleus retrograde signaling. Soon after the release of singlet oxygen ((1)O(2)) in chloroplasts of the flu mutant of Arabidopsis, reprogramming of nuclear gene expression reveals a rapid transfer 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.1202041109
更新日期:2012-10-02 00:00:00
abstract::Cajal-Retzius (CR) cells are early-generated transient neurons and are important in the regulation of cortical neuronal migration and cortical laminar formation. Molecular entities characterizing the CR cell identity, however, remain largely elusive. We purified mouse cortical CR cells expressing GFP to homogeneity 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.0406295101
更新日期:2004-10-05 00:00:00
abstract::A shuttle vector plasmid that contains sequences from simian virus 40, pBR322, and a bacterial marker gene, galactokinase, has been constructed. After replication in cells permissive for virus progeny, plasmid DNA was introduced into a galactokinase-deficient bacterial strain and the relative frequency of colonies wit...
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.80.10.3010
更新日期:1983-05-01 00:00:00
abstract::MST1, mammalian STE20-like kinase 1, is a serine/threonine kinase that is cleaved and activated by caspases during apoptosis. MST1 is capable of inducing apoptotic morphological changes such as chromatin condensation upon overexpression. In this study, we show that MST1 contains two functional nuclear export signals (...
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.181161698
更新日期:2001-08-28 00:00:00
abstract::Mutations in the human parkin gene cause autosomal recessive juvenile parkinsonism, a heritable form of Parkinson's disease (PD). To determine whether mutations in the mouse parkin gene (Park2) also result in a parkinsonian phenotype, we generated mice with a targeted deletion of parkin exon 2. Using an extensive beha...
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.0409598102
更新日期:2005-02-08 00:00:00
abstract::The remarkable fidelity of most DNA polymerases depends on a series of early steps in the reaction pathway which allow the selection of the correct nucleotide substrate, while excluding all incorrect ones, before the enzyme is committed to the chemical step of nucleotide incorporation. The conformational transitions 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.0910909107
更新日期:2010-01-12 00:00:00