Abstract:
:The temperature dependence of migration rate and of the thermotactic sensitivity of pseudoplasmodia of Dictyostelium discoideum has been measured. Migration rate increases with temperature to 20 degrees, is temperature insensitive from 20 degrees to 27.5 degrees, and decreases with temperature to 29 degrees, above which point migration ceases. However, pseudoplasmodia formed from cells grown at 23.5 degrees are thermotactic only from 22 degrees to 27.5 degrees. Thus, a temperature dependence of migration rate is not sufficient to explain thermotaxis. Because random lateral movements by the pseudoplasmodia have not been observed, the measurement of the temperature gradient appears to be spatial rather than temporal, with a half-maximal thermotactic response to a temperature gradient of about 0.04 degree/cm, or 0.0004 degree across an average pseudoplasmodium. Thermotactic sensitivity is adaptive, with pseudoplasmodia formed from cells grown at 20 degrees capable of thermotaxis at temperatures lower than cells grown at 23.5 degrees.
journal_name
Proc Natl Acad Sci U S Aauthors
Poff KL,Skokut Mdoi
10.1073/pnas.74.5.2007subject
Has Abstractpub_date
1977-05-01 00:00:00pages
2007-10issue
5eissn
0027-8424issn
1091-6490journal_volume
74pub_type
杂志文章abstract::For isolated rat hepatocytes, glucagon, 3':5'-cyclic AMP, 3':5'-cyclic GMP, and epinephrine stimulate the rate of gluconeogenesis from substrates not involving pathways of mitochondrial metabolism. From estimation of the rates of glucose formation, fructose 6-phosphate phosphorylation, and lactate and pyruvate formati...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.71.11.4523
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abstract::A mixture of two recombinant plasmids was microinjected into mouse thymidine kinase-negative fibroblasts (L cells). One plasmid contained the thymidine kinase gene of herpes simplex virus type I and the other contained the human beta globin gene. Seven fibroblast colonies arising from injected cells incubated in hypox...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.77.9.5399
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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
pub_type: 评论,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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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
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更新日期:2001-06-19 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:1988-04-01 00:00:00
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pub_type: 杂志文章,评审
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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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abstract::Viral genome packaging into capsids is powered by high-force-generating motor proteins. In the presence of all packaging components, ATP-powered translocation in vitro expels all detectable tightly bound YOYO-1 dye from packaged short dsDNA substrates and removes all aminoacridine dye from packaged genomic DNA in vivo...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-12-11 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: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
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更新日期:2011-11-29 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
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更新日期:1994-06-21 00:00:00