Abstract:
:A wide diversity of biological molecules are modified by the addition of sugar residues, and a large number of glycosyltransferases have been identified that are responsible for these reactions. Despite catalyzing closely related reactions, many of these transferases show little apparent sequence homology. By comparing two apparently unrelated families of yeast Golgi mannosyltransferases, a short motif containing two aspartate residues was observed that was conserved in both groups of proteins. Mutagenesis of one of the members of these families, the alpha-1, 3-mannosyltransferase Mnn1p, showed that altering either of these aspartates eliminates all enzymatic activity. These changes do not appear to affect the overall folding and assembly of Mnn1p. A similar aspartate-containing sequence was found to be conserved in a diverse range of other glycosyltransferase families, much more frequently than would be expected by chance, suggesting that it is a feature of the catalytic site, or an element of a structural fold, shared by many glycosyltransferases.
journal_name
Proc Natl Acad Sci U S Aauthors
Wiggins CA,Munro Sdoi
10.1073/pnas.95.14.7945subject
Has Abstractpub_date
1998-07-07 00:00:00pages
7945-50issue
14eissn
0027-8424issn
1091-6490journal_volume
95pub_type
杂志文章abstract::In Epstein-Barr virus (EBV)-positive Burkitt lymphoma (BL) the role of EBV in the translocation and deregulation of the MYC oncogene remains unknown. By utilizing an EBV-negative BL (BJAB) and several EBV-positive sublines derived from it by in vitro infection, it was possible to show that the presence of the virus wa...
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.84.16.5838
更新日期:1987-08-01 00:00:00
abstract::The outer membrane (OM) of Gram-negative bacteria is a permeability barrier and an intrinsic antibiotic resistance factor. Lipoproteins are OM components that function in cell wall synthesis, diverse secretion systems, and antibiotic efflux pumps. Moreover, each of the essential OM machines that assemble the barrier 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.1702248114
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1999-12-07 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2020-04-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Major histocompatibility complex (MHC) class I multimer technology has become an indispensable immunological assay system to dissect antigen-specific cytotoxic CD8(+) T cell responses by flow cytometry. However, the development of high-throughput assay systems, in which T cell responses against a multitude of epitopes...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-03-11 00:00:00
abstract::Murine mastocytoma cells treated with calcium ionophore A23187 produced a slow-reacting substance (SRS) that caused guinea pig ileum to contract. The response was reversed by the SRS antagonist FPL 55712. On the basis of isotope incorporation experiments, spectroscopy, and chemical degradations, the SRS was identified...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.0812889106
更新日期:2009-03-31 00:00:00
abstract::Patients with chronic ulcerative colitis (UC) are at high risk for developing colorectal cancer. In this study, archival formalin-fixed paraffin-embedded colonic tissue from patients with UC who developed carcinoma (CA) or high-grade dysplasia (HGD) was examined for changes in expression of the proinflammatory and mit...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2011-10-18 00:00:00
abstract::Extracellular cAMP plays a crucial role in regulating the developmental program of Dictyostelium discoideum, functioning as a chemotactic agent, as well as a signal that regulates expression of developmentally expressed genes. These activities appear to be mediated by a cell-surface receptor for cAMP. We have studied ...
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.84.4.1030
更新日期:1987-02-01 00:00:00
abstract::B7 family proteins provide costimulatory signals that regulate T cell responses. Here we report the third set of B7 family-related T cell inhibitory molecules with the identification of a homolog of the B7 family, B7x. It is expressed in immune cells, nonlymphoid tissues, and some tumor cell lines. B7x inhibits cell-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.1434299100
更新日期:2003-09-02 00:00:00
abstract::In recent years, advertisers and magazine editors have been widely criticized for taking digital photo retouching to an extreme. Impossibly thin, tall, and wrinkle- and blemish-free models are routinely splashed onto billboards, advertisements, and magazine covers. The ubiquity of these unrealistic and highly idealize...
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.1110747108
更新日期:2011-12-13 00:00:00
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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.73.8.2767
更新日期:1976-08-01 00:00:00
abstract::The balance between mitochondrial fusion and fission influences the reticular shape of mitochondria in yeasts. Little is known about whether mitochondria fusion occurs in plants. Plant mitochondria are usually more numerous and more grain-shaped than animal mitochondria. BLAST searches of the nuclear and mitochondrial...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2004-05-18 00:00:00
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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.76.5.2204
更新日期:1979-05-01 00:00:00
abstract::Measles still remains a major cause of childhood morbidity and mortality worldwide. Measles virus (MV) vaccines are highly successful, but the mechanism underlying their efficacy has been unclear. Here we report the crystal structure of the MV attachment protein, hemagglutinin, responsible for MV entry. The receptor-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.0707830104
更新日期:2007-12-04 00:00:00
abstract::Social status motivates much of human behavior. However, status may have been a relatively weak target of selection for much of human evolution if ancestral foragers tended to be more egalitarian. We test the "egalitarianism hypothesis" that status has a significantly smaller effect on reproductive success (RS) in for...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2016-09-27 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2006-08-08 00:00:00
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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.0502054102
更新日期:2005-10-11 00:00:00
abstract::A cancer DNA phenotype, identical to the DNA structure of tumors, has been identified in the prostate glands of certain healthy men over 55 years of age. We now show that the same DNA signature exists in normal tissues adjacent to tumors. This finding implies that the phenotype is maintained in normal prostate cells 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.0509630102
更新日期:2005-12-27 00:00:00
abstract::The auditory and motor neural systems are closely intertwined, enabling people to carry out tasks such as playing a musical instrument whose mapping between action and sound is extremely sophisticated. While the dorsal auditory stream has been shown to mediate these audio-motor transformations, little is known about h...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 临床试验,杂志文章
doi:10.1073/pnas.1721414115
更新日期:2018-06-26 00:00:00
abstract::Ubiquitination, the crucial posttranslational modification that regulates the eukaryotic proteome, is carried out by a trio of enzymes, known as E1 [ubiquitin (Ub)-activating enzyme], E2 (Ub-conjugating enzyme), and E3 (Ub ligase). Although most E2s can work with any of the three mechanistically distinct classes of E3...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2017-08-08 00:00:00
abstract::Human chromosome 22q11.2 has been implicated in various behavioral abnormalities, including schizophrenia and other neuropsychiatric/behavioral disorders. However, the specific genes within 22q11.2 that contribute to these disorders are still poorly understood. Here, we show that an approximately 200-kb segment of hum...
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.0509635102
更新日期:2005-12-27 00:00:00
abstract::Light emission produced by the reversible collapse of a cavity in a dielectric medium is given an initial, simplified treatment. The agreement between planar and spherical shapes indicates the volume nature of the effect. ...
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.90.3.958
更新日期:1993-02-01 00:00:00
abstract::The rotational strengths of the four longer wavelength transitions, B(2u), B(1u), and the two E(1u), of adenosine derivatives constrained in the syn form have been investigated theoretically and experimentally. The theory combines a complete neglect of differential overlap version S (CNDO/S) description of the base wi...
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.77.6.3398
更新日期:1980-06-01 00:00:00
abstract::The emergence of resistance to multiple unrelated chemotherapeutic drugs impedes the treatment of several cancers. Although the involvement of ATP-binding cassette transporters has long been known, there is no in situ method capable of tracking this transporter-related resistance at the single-cell level without inter...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2013-06-04 00:00:00
abstract::Because mouse models play a crucial role in biomedical research related to the human nervous system, understanding the similarities and differences between mouse and human brain is of fundamental importance. Studies comparing transcription in human and mouse have come to varied conclusions, in part because of their 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.0914257107
更新日期:2010-07-13 00:00:00
abstract::The soil-transmitted helminths or nematodes (hookworms, whipworms, and Ascaris) are roundworms that infect more than 1 billion of the poorest peoples and are leading causes of morbidity worldwide. Few anthelmintics are available for treatment, and only one is commonly used in mass drug administrations. New anthelminti...
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.0912327107
更新日期:2010-03-30 00:00:00
abstract::Rat cortical astrocytes in pure culture are functionally coupled to neighboring cells via connexin (Cx) 43 gap junctions under ordinary conditions. Small fluorescent molecules such as Lucifer yellow (LY) pass between cell interiors via gap junctions, but do not enter the cells when externally applied. Subjecting rat 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.012589799
更新日期:2002-01-08 00:00:00