Summary
Exponentially growing HeLa cells have been separated according to their cell cycle age by sedimenting at unit gravity for 3 hr on a phosphate-buffered sucrose density gradient. Measurements of cell size, cell number, DNA content, and tritiated thymidine incorporation in consecutive portions of the gradient showed that cells in upper fractions were in G1, cells in middle fractions were in S, and cells in lower fractions were in G2. Basic amino acids were rapidly incorporated into nuclear protein during late G1 and S; some incorporation also took place during G2.
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This work is supported by grant A-3458 from the National Research Council of Canada.
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Tang, SC., Sinclair, R. Unit gravity sedimentation analysis of basic nuclear protein synthesis during the HeLa cell cycle. In Vitro 8, 295–300 (1973). https://doi.org/10.1007/BF02615909
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DOI: https://doi.org/10.1007/BF02615909