scholarly journals THE SYNTHESIS OF DNA, RNA, AND NUCLEAR PROTEIN IN NORMAL AND TUMOR STRAIN CELLS

1966 ◽  
Vol 28 (2) ◽  
pp. 249-256 ◽  
Author(s):  
John Seed
Keyword(s):  
Dna Synthesis ◽  
Cell Cultures ◽  
Nuclear Protein ◽  
Mouse Cell ◽  
X Rays ◽  
Normal Tissues ◽  
Physical Measurements ◽  
Cytoplasmic Rna ◽  
Nuclear Rna ◽  
Photometric Measurements

Interferometric and photometric measurements have been made on replicating embryo mouse cell cultures. From a study of the relations between successive physical measurements on individual cells, it was found that the net syntheses of DNA, nuclear RNA, nuclear protein, and cytoplasmic RNA are closely associated during interphase. In auxiliary experiments, an inhibition of the onset of DNA synthesis (produced by a dose of X-rays) was found to block the majority of the accumulation of nuclear protein and nuclear RNA. These results are consistent with others previously reported in dividing cell cultures freshly prepared from normal tissues.

scholarly journals THE SYNTHESIS OF DNA, RNA, AND NUCLEAR PROTEIN IN NORMAL AND TUMOR STRAIN CELLS

1966 ◽  
Vol 28 (2) ◽  
pp. 233-248 ◽  
Author(s):  
John Seed
Keyword(s):  
Cell Cultures ◽  
Nuclear Protein ◽  
Kidney Cells ◽  
X Rays ◽  
Normal Tissues ◽  
Physical Measurements ◽  
Cytoplasmic Rna ◽  
Human Cell Cultures ◽  
Nuclear Rna ◽  
Photometric Measurements

Interferometric and photometric measurements have been made on replicating embryo human cell cultures. From a study of the relations between successive physical measurements on individual cells, it was found that the net syntheses of DNA, nuclear RNA, nuclear protein, and cytoplasmic RNA are closely associated during interphase. Additional measurements of DNA and cytoplasmic RNA on freshly prepared replicating monkey kidney cells gave similar results. In auxiliary experiments with embryo human cells, an inhibition of the onset of DNA synthesis (produced by a dose of X-rays) was found to block the majority of the accumulation of nuclear protein and RNA and about half the accumulation of cytoplasmic RNA. These results are consistent with others previously reported in dividing cell cultures freshly prepared from normal tissues.

scholarly journals THE SYNTHESIS OF DNA, RNA, AND NUCLEAR PROTEIN IN NORMAL AND TUMOR STRAIN CELLS

1966 ◽  
Vol 28 (2) ◽  
pp. 263-275 ◽  
Author(s):  
John Seed
Keyword(s):  
Dna Replication ◽  
Dna Synthesis ◽  
Hela Cells ◽  
Nuclear Protein ◽  
X Rays ◽  
Normal Cells ◽  
Human Carcinoma ◽  
Physical Measurements ◽  
Cytoplasmic Rna ◽  
Nuclear Rna

Interferometric and photometric measurements have been made on HeLa cells, a strain of cells originally derived from a human carcinoma. From a study of the relations between successive physical measurements on individual cells, it was confirmed that, whereas the net syntheses of nuclear RNA and nuclear protein are closely associated during interphase, they are dissociated from DNA replication to a significant extent. These results on nuclear metabolism agree with others previously reported in cell strains derived from tumors; they contrast with results from freshly prepared normal cells, where the net syntheses of DNA, nuclear RNA, and protein are closely associated during interphase. Cytoplasmic measurements on HeLa cells showed that much of the net synthesis of cytoplasmic RNA is associated with DNA replication as in normal cells, and they failed to detect transfer from the nucleus of a stable RNA component synthesized independently from DNA replication. In auxiliary experiments, an inhibition of the onset of DNA synthesis was produced by a dose of X-rays; under these conditions it was shown that the major part of the accumulation of nuclear protein was independent of DNA replication and that the accumulation of nuclear RNA was equivalent to or slightly less than that of nuclear protein. About half the accumulation of cytoplasmic RNA was inhibited when DNA synthesis was blocked.

scholarly journals THE SYNTHESIS OF DNA, RNA, AND NUCLEAR PROTEIN IN NORMAL AND TUMOR STRAIN CELLS

1966 ◽  
Vol 28 (2) ◽  
pp. 257-261 ◽  
Author(s):  
John Seed
Keyword(s):  
Dna Synthesis ◽  
Nuclear Protein ◽  
Ascites Tumor ◽  
Significant Extent ◽  
Physical Measurements ◽  
Nuclear Rna ◽  
X Irradiation ◽  
Mouse Ascites ◽  
Cell Strains ◽  
Photometric Measurements

Interferometric and photometric measurements have been made on replicating mouse ascites tumor cell cultures. From a study of the relations between successive physical measurements on individual cells, it was found that whereas the net syntheses of nuclear RNA and nuclear protein are closely associated during interphase, they are dissociated from DNA replication to a significant extent. These results agree with others reported in replicating cell strains derived from tumors. In auxiliary experiments an attempt was made to block the initiation of DNA synthesis by X-irradiation: although large amounts of nuclear protein accumulated in some cells in the absence of DNA synthesis, the inability to hold the DNA block for an interphase time prevented a quantitative analysis of the results.

CHLOROPHYLL, PROTEIN, AND NUCLEIC ACID LEVELS IN DETACHED, SENESCING WHEAT LEAVES

1965 ◽  
Vol 43 (6) ◽  
pp. 739-746 ◽  
Author(s):  
Michael Shaw ◽  
P. K. Bhattacharya ◽  
W. A. Quick
Keyword(s):  
Nucleic Acid ◽  
Oxygen Uptake ◽  
Nucleic Acids ◽  
Nuclear Protein ◽  
Fresh Weight ◽  
Rapid Loss ◽  
Nuclear Rna ◽  
Chlorophyll Protein ◽  
Chloroplast Rna ◽  
Wheat Leaves

Excised primary leaves of Little Club and Khapli wheats were allowed to senesce on water or on kinetin (10 mg/l.) for 6 to 8 days. Histological sections taken at 2-day intervals were stained for RNA, DNA, histone, and total protein. Twenty-five or thirty leaves were analyzed daily for chlorophyll, protein, and nucleic acids. Oxygen uptake was also measured. Examination of the sections showed that leaves senescing on water underwent rapid losses in chloroplast RNA and protein and in nuclear RNA. Losses in DNA, histone, and total nuclear protein were delayed until the nuclei disintegrated. These observations are correlated with the analytical results. The latter revealed statistically significant losses in chlorophyll, protein, and nucleic acid contents with time. The losses in nucleic acids were due mainly, if not entirely, to losses in RNA. Oxygen uptake per gram fresh weight in the leaves on water did not change significantly with days after excision. Kinetin significantly delayed losses in chlorophyll, RNA, and protein, and depressed oxygen uptake. Certain differences between the two varieties of wheat are described, including the more rapid loss of nucleic acid in Khapli.

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