Abstract:
:Two Chinese hamster cell lines, G1+-1 and CHO, have been grown in the presence of low concentrations of hydroxyurea to determine how a slowing DNA synthesis (i.e., a lengthening of the S period) affects the length of the G1 period. Hydroxyurea concentrations of approximately 10 microM do not alter the generation times of these cell lines but do cause increases in S with corresponding decreases in G1. In both cell lines, 10 microM hydroxyurea reduces G1 to an absolute value of 1 hr, which represents decreases of 70% (G1+-1) and 60% (CHO) from control values. Higher concentrations of hydroxyurea increase the generation times and lengths of S for both cell lines but do not reduce G1 below the minimum value of 1 hr. These observations indicate that the majority of G1 is expendable and most of G1 therefore cannot contain specific events required for the initiation of DNA synthesis. This result supports the hypothesis that G1 is a portion of the cell growth cycle but not of the chromosome cycle.
journal_name
Proc Natl Acad Sci U S Aauthors
Stancel GM,Prescott DM,Liskay RMdoi
10.1073/pnas.78.10.6295subject
Has Abstractpub_date
1981-10-01 00:00:00pages
6295-8issue
10eissn
0027-8424issn
1091-6490journal_volume
78pub_type
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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:1982-12-01 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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更新日期:1977-03-01 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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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:2004-07-27 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:2015-07-14 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:1985-03-01 00:00:00