Abstract:
:Most higher eukaryotic tubulins are separated into alpha- and beta-tubulin when electrophoresed in NaDodSO4- denaturing gels, while many lower eukaryotic tubulins are poorly resolved under these conditions, which include a stacking gel (pH 6.80) and a separating gel (pH 8.80). By lowering the pH of the separating gel to 8.25, we have found that tubulin isolated from the protozoan Tetrahymena thermophila is resolved by one-dimensional polyacrylamide gel electrophoresis into two alpha-tubulins and one beta-tubulin. Moreover, at least five alpha- and two beta-tubulin isotypes are identified in Tetrahymena by isoelectric focusing and two-dimensional polyacrylamide gel electrophoresis. Three of these alpha isotypes and one beta isotype are found specifically in ciliary microtubules, while the other two isotypes are found only in the cytoplasmic tubulin pool that was isolated and induced to self-assemble into microtubules in vitro. Peptide mapping by limited proteolytic digestion indicates that the tubulins are closely related. Possible mechanisms for the generation and selection of these tubulin isotypes are discussed.
journal_name
Proc Natl Acad Sci U S Aauthors
Suprenant KA,Hays E,LeCluyse E,Dentler WLdoi
10.1073/pnas.82.20.6908subject
Has Abstractpub_date
1985-10-01 00:00:00pages
6908-12issue
20eissn
0027-8424issn
1091-6490journal_volume
82pub_type
杂志文章abstract::Node characteristics and behaviors are often correlated with the structure of social networks over time. While evidence of this type of assortative mixing and temporal clustering of behaviors among linked nodes is used to support claims of peer influence and social contagion in networks, homophily may also explain suc...
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.0908800106
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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.0406472102
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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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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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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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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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1987-12-01 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1984-04-01 00:00:00