Abstract:
:Protein synthesis initiation in reticulocyte lysates is inhibited by heme deficiency, low levels of double-stranded RNA (dsRNA), oxidized glutathione (GSSG), or the purified kinase (HRI) that acts on the alpha polypeptide of eukaryotic initiation factor 2 (eIF-2alpha). The phosphoprotein profiles produced in lysates in response to these various conditions have been monitored directly in lysates after labeling for brief periods with pulses of [gamma-(32)P]ATP. The [(32)P]phosphoprotein profiles were analyzed by electrophoresis in sodium dodecyl sulfate/polyacrylamide slab gels under conditions in which the HRI and eIF-2alpha polypeptides were clearly distinguished. All four modes of inhibition produced a rapid phosphorylation of eIF-2alpha compared to control lysates, which displayed little or no phosphorylation of eIF-2alpha. In heme-deficient lysates, phosphorylation of eIF-2alpha occurred rapidly both before and after the shut-off of protein synthesis; the delayed addition of hemin to these lysates resulted in a decrease in the phosphorylation of eIF-2alpha and the subsequent restoration of protein synthesis. These data suggest that rapid turnover of phosphate occurs at the site(s) of eIF-2alpha phosphorylation. In lysates inhibited by heme deficiency, GSSG, or added HRI, the phosphorylation of eIF-2alpha was accompanied by the rapid in situ phosphorylation of HRI. The inhibition of initiation induced by dsRNA was accompanied by the phosphorylation of eIF-2alpha and a 67,000-dalton polypeptide but not HRI. These observations in situ indicate that (i) the phosphorylation of eIF-2alpha is the critical event in these inhibitions of protein chain initiation, and (ii) the phosphorylation of HRI is associated with its activation in heme deficiency.
journal_name
Proc Natl Acad Sci U S Aauthors
Ernst V,Levin DH,London IMdoi
10.1073/pnas.76.5.2118subject
Has Abstractpub_date
1979-05-01 00:00:00pages
2118-22issue
5eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章abstract::The transforming growth factors beta (TGF-beta s) are important modulators of growth and differentiation. They are intermolecular disulfide-bonded homodimeric molecules. The monomer fold has a conserved cystine knot and lacks a hydrophobic core. The biological specificity of a given member of the family is believed to...
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.92.12.5406
更新日期:1995-06-06 00:00:00
abstract::We previously isolated from mouse spleen an octapeptide (LSPFPFDL) that in association with the class I major histocompatibility complex protein Ld is recognized by the antigen-specific receptor of an alloreactive CD8+ T-cell clone (2C). Guided by an assay dependent upon the same 2C T-cell receptor, we have now isolat...
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.90.23.11272
更新日期:1993-12-01 00:00:00
abstract::Metastasis, the truly lethal aspect of cancer, occurs when metastatic cancer cells in a tumor break through the basement membrane and penetrate the extracellular matrix. We show that MDA-MB-231 metastatic breast cancer cells cooperatively invade a 3D collagen matrix while following a glucose gradient. The invasion fro...
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:2013-01-29 00:00:00
abstract::Aggregation of marine sponge cells (Microciona prolifera) resembles stimulus-response coupling of higher organisms in which activation of protein kinase C and movements of intracellular Ca provide twin signals. We now report that activators of protein kinase C (phorbol esters) and ionomycin act synergistically to aggr...
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.83.9.2914
更新日期:1986-05-01 00:00:00
abstract::Genetic evidence indicates that the PrlA (SecY) protein of Escherichia coli functions as a membrane integrated signal sequence receptor in protein "export"--i.e., in protein translocation across (or integration into) the plasma membrane. We have raised antibodies in rabbits against two synthetic peptides representing ...
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.86.6.1895
更新日期:1989-03-01 00:00:00
abstract::The reversible phosphorylation of tyrosine residues is an important mechanism for modulating biological processes such as cellular signaling, differentiation, and growth, and if deregulated, can result in various types of cancer. Therefore, an understanding of these dynamic cellular processes at the molecular level 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.2436191100
更新日期:2003-01-21 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:2011-09-13 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.1617330114
更新日期:2017-07-11 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.90.1.25
更新日期:1993-01-01 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.83.18.6915
更新日期:1986-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1995-02-14 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.1221924110
更新日期:2013-02-26 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.1110889108
更新日期:2011-10-18 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
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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.86.16.6133
更新日期:1989-08-01 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
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更新日期:2015-04-07 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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更新日期:2008-12-16 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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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:2008-10-14 00:00:00
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更新日期:1998-10-13 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
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更新日期:2016-04-05 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:2014-07-15 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.96.3.986
更新日期:1999-02-02 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.77.5.2839
更新日期:1980-05-01 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
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更新日期:2004-04-20 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:2014-07-08 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.1212593110
更新日期:2013-07-23 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: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
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更新日期:1994-05-24 00:00:00