Abstract:
:A single anterior-animal blastomere, which includes the presumptive neural region in the eight-cell embryo of the Halocynthia, a protochordate, when dissociated, cleavage-arrested with cytochalasin B, and cultured in isolation, differentiated exclusively to epidermal type judging from membrane excitability and immunoreactivity. However, when the same blastomere was cultured in contact with a single anterior-vegetal blastomere, which includes the presumptive notochordal region, it displayed Na spikes and showed no expression of the epidermal antigen, suggesting that "neural induction" resulted in a single cell during the interaction with a single neighboring cell. This simple two-cell system can be used for further studies on the induction mechanism.
journal_name
Proc Natl Acad Sci U S Aauthors
Okado H,Takahashi Kdoi
10.1073/pnas.85.16.6197subject
Has Abstractpub_date
1988-08-01 00:00:00pages
6197-201issue
16eissn
0027-8424issn
1091-6490journal_volume
85pub_type
杂志文章abstract::The density of corn pollen on leaves of milkweed plants inside and outside of cornfields was measured in several studies from different localities. The purpose was to obtain a representative picture of naturally occurring pollen densities to provide a perspective for laboratory and field studies of monarch larvae feed...
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.211287498
更新日期:2001-10-09 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.1707453114
更新日期:2017-09-19 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.0701685104
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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.97.10.5540
更新日期:2000-05-09 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.0402221101
更新日期:2004-05-11 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.1107807108
更新日期:2011-06-28 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
pub_type: 杂志文章
doi:10.1073/pnas.1701952114
更新日期:2017-04-25 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:2009-12-08 00:00:00
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更新日期:2011-05-17 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.1813268116
更新日期:2019-02-26 00:00:00
abstract::There are some ∼1,100 known antimicrobial peptides (AMPs), which permeabilize microbial membranes but have diverse sequences. Here, we develop a support vector machine (SVM)-based classifier to investigate ⍺-helical AMPs and the interrelated nature of their functional commonality and sequence homology. SVM is used 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.1609893113
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.75.10.4935
更新日期:1978-10-01 00:00:00
abstract::Activation of eukaryotic class II gene expression involves the formation of a transcription initiation complex that includes RNA polymerase II, general transcription factors, and SRB components of the holoenzyme. Negative regulators of transcription have been described, but it is not clear whether any are general repr...
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.94.7.3145
更新日期:1997-04-01 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.85.5.1722
更新日期:1988-03-01 00:00:00
abstract::The Rhizobium common nod gene products NodABC are involved in the synthesis of the core lipochitooligosaccharide (Nod factor) structure, whereas the products of the host-specific nod genes are necessary for diverse structural modifications, which vary in different Rhizobium species. The sulfate group attached to the 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.92.7.2706
更新日期:1995-03-28 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.2017421118
更新日期:2021-02-02 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.0404195101
更新日期:2004-07-20 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:1996-08-06 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.91.26.12937
更新日期:1994-12-20 00:00:00
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更新日期:2020-01-21 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:1998-05-26 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.87.21.8602
更新日期:1990-11-01 00:00:00
abstract::Most of the activities of IFN-gamma are the result of STAT1-mediated transcriptional responses. In this study, we show that the BRCA1 tumor suppressor acts in concert with STAT1 to differentially activate transcription of a subset of IFN-gamma target genes and mediates growth inhibition by this cytokine. After IFN-gam...
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.080469697
更新日期:2000-05-09 00:00:00
abstract::The lamB protein, the receptor for phage lambda, was purified from the outer membrane of Escherichia coli K-12 by extraction with Triton X-100 and EDTA, chromatography on DEAE-Sephacel in Triton X-100, exchange of Triton for cholate by gel filtration, and chromatography on Sephacryl S-200 in cholate, NaCl, and EDTA. T...
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:1980-01-01 00:00:00
abstract::We have isolated and partially characterized an endonuclease involved in processing the 5' end of 16S rRNA of Escherichia coli. A mutant strain that is deficient in this enzyme accumulates a new precursor of 16S rRNA, named 16.3S rRNA. This rRNA has the 3' end of mature 16S rRNA but is about 60 nucleotides longer 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.75.8.3598
更新日期:1978-08-01 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:2003-07-22 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.0704853104
更新日期:2007-07-03 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.1304859110
更新日期:2013-07-30 00:00:00
abstract::The primary product of biological nitrogen fixation, ammonia, reversibly regulates nitrogenase activity in a variety of diazotrophs by a process called "NH4(+)-switch-off/on." Strong correlative evidence from work in Azospirillum lipoferum and Rhodospirillum rubrum indicates that this regulation involves both the inac...
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.87.5.1720
更新日期:1990-03-01 00:00:00