Identification of two human phosphoproteins (dividin and IEF 59dl) that are first detected late in G1 near the G1/S transition border of the cell cycle.
Two-dimensional gel electrophoretic analysis (NEPHGE, IEF) of the [32P]-orthophosphate-labeled proteins synthesized throughout the cell cycle of transformed human amnion cells (AMA) revealed two phosphoproteins (dividin, Mr = 54,000, pl = 8.4; IEF 59dl, Mr = 27,000, pl = 5.7) that are present mainly in S-phase cells. These proteins are first detected at the end of G1, near the G1/S transition border, and their levels reach a maximum late in S-phase. Together with the previously identified nuclear protein cyclin, these phosphoproteins are likely candidates for proteins that may play a role in the regulation of the onset of DNA synthesis and cell division.
Nielsen
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S
Department of Medical Biochemistry, Aarhus University, Denmark.
Celis
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A
Ratz
G P
GP
Celis
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D000650:Amnion; D002453:Cell Cycle; D002461:Cell Line, Transformed; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007399:Interphase; D007526:Isoelectric Point; D008938:Mitosis; D008970:Molecular Weight; D010750:Phosphoproteins / Q000378:metabolism*
D010750:Phosphoproteins; C053990:dividin