Abstract：
:When a mutant of Saccharomyces cerevisiae (spe2 delta) that cannot make spermidine or spermine was incubated in a polyamine-deficient medium in oxygen, there was a rapid cessation of cell growth and associated cell death. In contrast, when the mutant cells were incubated in the polyamine-deficient medium in air or anaerobically, the culture stopped growing more gradually, and there was no significant loss of cell viability. We also found that the polyamine-deficient cells grown in air, but not those grown anaerobically, showed a permanent loss of functional mitochondria ("respiratory competency"), as evidenced by their inability to grow on glycerol as the sole carbon source. These data support the postulation that polyamines act, in part, by protecting cell components from damage resulting from oxidation. However, since the mutant cells still required spermidine or spermine for growth when incubated under strictly anaerobic conditions, polyamines must also have other essential functions.
journal_name
Proc Natl Acad Sci U S Aauthors
Balasundaram D,Tabor CW,Tabor Hdoi
10.1073/pnas.90.10.4693subject
Has Abstractpub_date
1993-05-15 00:00:00pages
4693-7issue
10eissn
0027-8424issn
1091-6490journal_volume
90pub_type
杂志文章abstract：:Peripheral blood mononuclear cells of 10 out of 26 patients with human immunodeficiency virus type 1 (HIV-1) released IgE-binding factors, as determined by two independent assays. The formation of the factors by the mononuclear cells was enhanced by incubation of the cells with homologous IgE. In the presence of IgE, ...
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.85.23.9214
更新日期：1988-12-01 00:00:00
abstract：:Proliferating 3T3 mouse fibroblasts contain higher levels of the lectin carbohydrate-binding protein 35 (CBP35) than do quiescent cultures of the same cells. An immunofluorescence study was carried out with a rabbit antiserum directed against CBP35 to map the cellular fluorescence distribution in a large population 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.84.18.6452
更新日期：1987-09-01 00:00:00
abstract：:We previously reported that short-term immobilization stress of rats causes increased colonic mucin release, goblet cell depletion, prostaglandin E2 secretion, and colonic mast cell activation, as well as increased colonic motility. The purpose of this study was to investigate whether neurotensin (NT), a peptide expre...
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.93.22.12611
更新日期：1996-10-29 00:00:00
abstract：:Glands of the uterus are essential for pregnancy establishment. Forkhead box A2 (FOXA2) is expressed specifically in the glands of the uterus and a critical regulator of glandular epithelium (GE) differentiation, development, and function. Mice with a conditional deletion of FOXA2 in the adult uterus, created using 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.2014272117
更新日期：2020-09-22 00:00:00
abstract：:The content of elongation factor Tu in E. coli B has been determined both by radioimmune assay and by GDP binding. The two assays gave comparable results: cells growing at 2 doublings per hour contained about 8 molecules of Tu per ribosome, whereas those growing at 0.22 doublings per hour contained about 14 molecules ...
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.72.12.4780
更新日期：1975-12-01 00:00:00
abstract：:The discipline-wide effort to database the fossil record at the occurrence level has made it possible to estimate marine invertebrate extinction and origination rates with much greater accuracy. The new data show that two biotic mechanisms have hastened recoveries from mass extinctions and confined diversity to a rela...
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.0802597105
更新日期：2008-08-12 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.70.12.3445
更新日期：1973-12-01 00:00:00
abstract：:This study describes a unique function of taurocholate in bile canalicular formation involving signaling through a cAMP-Epac-MEK-Rap1-LKB1-AMPK pathway. In rat hepatocyte sandwich cultures, polarization was manifested by sequential progression of bile canaliculi from small structures to a fully branched network. Tauro...
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.1018376108
更新日期：2011-01-25 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.1519990113
更新日期：2016-03-01 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.1616216114
更新日期：2017-04-18 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.94.21.11393
更新日期：1997-10-14 00:00:00
abstract：:D gene segments with irregular spacers (DIR) are D gene segments that are specific to higher primates. Their use is controversial because of their G+C-rich long sequences. In the human, it has always been tempting to assume that a complementarity-determining region 3 sequence has been added by terminal deoxynucleotidy...
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.95.4.1703
更新日期：1998-02-17 00:00:00
abstract：:The early reactions in the catabolism of quinic acid in Neurospora crassa are controlled by at least four genes which are clustered on linkage group VII. Three of the loci (qa-2, qa-4, and qa-3) encode enzymes that convert quinic acid to protocatechuic acid. The fourth gene (qa-1) encodes a positive regulatory protein...
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.78.8.5086
更新日期：1981-08-01 00:00:00
abstract：:Converging TGF-beta and insulin-like neuroendocrine signaling pathways regulate whether Caenorhabditis elegans develops reproductively or arrests at the dauer larval stage. We examined whether neurotransmitters act in the dauer entry or recovery pathways. Muscarinic agonists promote recovery from dauer arrest induced ...
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.97.1.460
更新日期：2000-01-04 00:00:00
abstract：:We propose that retroviruses exploit a cell-encoded pathway of intercellular vesicle traffic, exosome exchange, for both the biogenesis of retroviral particles and a low-efficiency but mechanistically important mode of infection. This Trojan exosome hypothesis reconciles current paradigms of retrovirus-directed transm...
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.1831413100
更新日期：2003-09-16 00:00:00
abstract：:Nutrition recommendations worldwide emphasize ingestion of plant-based diets rather than diets that rely primarily on animal products. However, this plant-based diet could limit the intake of essential nutrients such as calcium. Osteoporosis is one of the world's most prevalent nutritional disorders, and inadequate di...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
pub_type： 杂志文章,随机对照试验
doi：10.1073/pnas.0709005105
更新日期：2008-02-05 00:00:00
abstract：:The number of x-irradiated mammalian cells surviving is markedly increased when the cells are incubated with an uncoupler of oxidative phosphorylation prior to or immediately after irradiation. This increase is greater in plateau-phase cells than in exponentially growing cells. The increase in survival is related to 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.77.5.2702
更新日期：1980-05-01 00:00:00
abstract：:Competition for mates can be a major source of selection, not just on secondary sexual traits but across the genome. Mate competition strengthens selection on males via sexual selection, which typically favors healthy, vigorous individuals and, thus, all genetic variants that increase overall quality. However, recent ...
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.1805435115
更新日期：2018-06-26 00:00:00
abstract：:Teratocarcinoma is a germ-line carcinoma giving rise to an embryoid tumor with structures derived from the three embryonic layers: mesoderm, endoderm, and ectoderm. Teratocarcinoma is widely used as an in vitro model system to study regulation of cell determination and differentiation during mammalian embryogenesis. M...
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.91.13.6088
更新日期：1994-06-21 00:00:00
abstract：:Kelp forests (Order Laminariales) form key biogenic habitats in coastal regions of temperate and Arctic seas worldwide, providing ecosystem services valued in the range of billions of dollars annually. Although local evidence suggests that kelp forests are increasingly threatened by a variety of stressors, no comprehe...
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.1606102113
更新日期：2016-11-29 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.62.3.715
更新日期：1969-03-01 00:00:00
abstract：:The bacteriophage T4-encoded RegB endoribonuclease is produced during the early stage of phage development and targets mostly (but not exclusively) the Shine-Dalgarno sequences of early genes. In this work, we show that the degradation of RegB-cleaved mRNAs depends on a functional T4 polynucleotide kinase/phosphatase ...
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.1119802109
更新日期：2012-05-01 00:00:00
abstract：:For more than a century we have understood that our brain's left hemisphere is the primary site for processing language, yet why this is so has remained more elusive. Using positron emission tomography, we report cerebral blood flow activity in profoundly deaf signers processing specific aspects of sign language in ke...
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.97.25.13961
更新日期：2000-12-05 00:00:00
abstract：:Oxygen-derived free radicals have been implicated in the pathogenesis of vasogenic edema and infarction caused by ischemia and reperfusion injury. In earlier studies, exogenously supplied liposome-entrapped CuZn superoxide dismutase (CuZn-SOD) ameliorated ischemic brain edema and infarction in rats following focal cer...
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.88.24.11158
更新日期：1991-12-15 00:00:00
abstract：:Alpha-Klotho (alpha-Kl) and its homolog, beta-Klotho (beta-Kl) are key regulators of mineral homeostasis and bile acid/cholesterol metabolism, respectively. FGF15/ humanFGF19, FGF21, and FGF23, members of the FGF19 subfamily, are believed to act as circulating metabolic regulators. Analyses of functional interactions ...
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.0913986107
更新日期：2010-01-26 00:00:00
abstract：:Forebrain cholinergic neurons play important roles as striatal local circuit neurons and basal telencephalic projection neurons. The genetic mechanisms that control development of these neurons suggest that most of them are derived from the basal telencephalon where Lhx8, a LIM-homeobox gene, is expressed. Here we rep...
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.1537759100
更新日期：2003-07-22 00:00:00
abstract：:Ras is a guanine nucleotide-binding protein that cycles between inactive GDP-bound and active GTP-bound states to regulate a diverse array of cellular processes, including cell growth, apoptosis, and differentiation. The guanine nucleotide-bound state of Ras is tightly maintained by regulatory factors to promote regul...
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.1037299100
更新日期：2003-05-27 00:00:00
abstract：:Heavy (H) chain binding protein (BiP), which binds to free immunoglobulin H chain of the mu and gamma classes, can be demonstrated in pre-B-cells. It is proposed that the displacement of BiP from H chain by light (L) chain terminates the activity of the enzyme system, L-generase, which catalyzes DNA rearrangement at 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.79.22.6976
更新日期：1982-11-01 00:00:00
abstract：:Dimyristoyl lecithin liposomes, containing cytochrome b5 reductase (NADH:ferricytochrome b5 oxidoreductase, EC 1.6.2.2) and varying amounts of cytochrome b5, were used to measure flavoprotein catalysis alone and catalysis requiring electron transfer between the reductase and cytochrome as a function of temperature. Wh...
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.72.7.2658
更新日期：1975-07-01 00:00:00
abstract：:Although microtubules (MTs) frequently form highly dynamic networks, subsets of MTs become stabilized in response to environmental cues and function as specialized tracks for vesicle and macromolecular trafficking. MT stabilization is controlled by specialized plus-end tracking proteins (+TIPs) whose accumulation at 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.1310760110
更新日期：2013-11-05 00:00:00
