scholarly journals CELL CYCLE EVENTS IN THE HYDROCORTISONE REGULATION OF ALKALINE PHOSPHATASE IN HELA S3 CELLS

1969 ◽  
Vol 40 (2) ◽  
pp. 297-304 ◽  
Author(s):  
M. J. Griffin ◽  
R. Ber
Keyword(s):  
Cell Cycle ◽  
Alkaline Phosphatase ◽  
Control Cell ◽  
Selective Permeability ◽  
Inductive Effects ◽  
Synchronous Cell ◽  
Lag Period ◽  
Hela S3 ◽  
Synthetic Phase ◽  
Hela S3 Cells

The increase in alkaline phosphatase in asynchronous cultures of HeLa S3 cells grown in medium supplemented with hydrocortisone is characterized by a lag period of 10–12 hr. Present studies utilizing synchronous cell populations indicate: (a) a minimum of 8–10 hr of incubation with hydrocortisone is necessary for maximum induction of alkaline phosphatase; (b) the increase in enzyme activity produced by hydrocortisone is initiated exclusively in the synthetic phase of the cell cycle; (c) alkaline phosphatase activity does not vary appreciably over a normal control cell cycle. Radioactive hydrocortisone is rapidly distributed into HeLa cells irrespective of their position in the cell cycle, indicating that inductive effects are not governed by selective permeability during the cell cycle. Hydrocortisone-1,2-[3H] diffuses back from the cell into the medium when the cells are incubated in fresh medium containing no hydrocortisone, and the alkaline phosphatase induction, under these conditions, is completely reversible.

X-ray microanalysis of HeLa S3 cells. II. Analysis of elemental levels during the cell cycle

1983 ◽  
Vol 62 (1) ◽  
pp. 339-350
Author(s):  
A. Warley ◽  
J. Stephen ◽  
A. Hockaday ◽  
T.C. Appleton
Keyword(s):  
Cell Cycle ◽  
Monovalent Cation ◽  
The Other ◽  
G1 Phase ◽  
Sodium Potassium ◽  
X Ray ◽  
Cation Concentration ◽  
Cell Compartments ◽  
Hela S3 ◽  
Hela S3 Cells

HeLa S3 cells were synchronized using hydroxyurea. Cryoultramicrotomy and X-ray microanalysis were used to study changes occurring in concentrations of elements during the cell cycle of the synchronized cells. Three subcellular compartments were studied: cytoplasm, nucleus and nucleolus. Potassium concentrations showed little fluctuation in all of the cell compartments during the cell cycle. Sodium concentrations increased during S. and M phases, returning to lower levels in the G1 phase. Chlorine concentrations were highest during the S and G2 phases. At all stages of the cell cycle respective concentrations of potassium, sodium, sulphur and chlorine were similar in the cytoplasm and nucleus. Concentrations of phosphorus increased in the nucleus during S, G2 and M, and also showed fluctuations in the nucleolus during the cycle; these were not seen in the cytoplasm. In S, M and M/G1 sodium concentrations were highest in the nucleolus compared with the other compartments. In the cytoplasm these changes resulted in an increase in total monovalent cation concentration (i.e. sodium + potassium) during S, G2 and M, which returned to base levels after mitosis. This increase in monovalent cation concentration is due almost entirely to the increase in sodium, with little change occurring in the concentration of potassium.

Histone proteins in HeLa S3 cells are synthesized in a cell cycle stage specific manner

Science ◽  
1982 ◽  
Vol 215 (4533) ◽  
pp. 683-685 ◽  
Author(s):  
F Marashi ◽  
L Baumbach ◽  
R Rickles ◽  
F Sierra ◽  
J. Stein ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Histone Proteins ◽  
Cell Cycle Stage ◽  
Specific Manner ◽  
A Cell ◽  
Hela S3 ◽  
Hela S3 Cells
Sign in / Sign up

Export Citation Format

Share Document