THE SIMULTANEOUS LABELING OF CELLS IN DIFFERENT SEGMENTS OF THE MITOTIC CYCLE WITH TRITIATED THYMIDINE AND COLCHICINE AND THE EFFECT OF COLCHICINE ON THYMIDINE UPTAKE

Technical Report · Tue Jan 01 04:00:00 EST 1963

OSTI ID:4090646

Van't Hof, J; Ying, H

Treatment of Pisum root meristems with nutrient solutions containing tritiated thymidine (H/sup 3/-T) and colchicine simultaneously labeled cells in two different segments of the mitotic cycle. Tracings of the serial progression of these differently labeled cells through mitosis resembled sine-cosine curves. When the labeled cells are in interphase the sign of the curves is negative, when they are in mitosis the sign is positive. The concept of the mitotic cycle in terms of trigonometric functions was presented as one way of transferring the cycle from a celestial time scale to that of a biological clock. The mitotic cycle time determined by the colchicine method was 14 hours at 20 deg C. The cycle time was 14.25 hours if the ascending portions of a curve representing two successive appearances of H/sup 3/-T labeled mitotic figures was used as a measurement. Use of the proportion of H/sup 3/-T labeled interphase cells and the S period duration produced a cycle time of 21.4 hours. The doubling of DNA content by colchicine did not increase the cycle time. Colchicine did prevent the H/sup 3/-T labeling of a large number of late S period cells when the two labels were either presented to meristems simultaneously or if colchicine treatment preceded H/sup 3/-T exposure. The use of colchicine and H/sup 3/-T as cellular labels and the kinetic variables on which they depend were also discussed. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• DOE Contract Number: AT(30-2)-GEN-16
• NSA Number: NSA-18-013413
• OSTI ID: 4090646
• Report Number(s): BNL-7317
• Country of Publication: United States
• Language: English

Related Subjects

ALKALOIDS
BIOLOGY AND MEDICINE
COLCHICINE
DIAGRAMS
DNA
LABELLED COMPOUNDS
MATHEMATICS
MEASURED VALUES
MITOSIS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PISUM
PLANT CELLS
ROOTS
SOLUTIONS
TEMPERATURE
THYMIDINE
TRITIUM
VARIATIONS