Tissue Culture Studies on Vicia Faba
IV. Effect of growth factors on mitotic activity
1964 Volume 29 Issue 3 Pages 298-310
Details
1964 Volume 29 Issue 3 Pages 298-310
The effects of commercially available nucleic acids, their salts or their precursors added to a culture medium on the mitotic activity of cultured cells of Vicia faba under liquid shaking conditions have been reported.
The addition of intact DNA or RNA to the control medium did not reveal any considerable effect on the growth rate of the cell aggregates whereas the addition of sodium salts of DNA or RNA at low concentration of 0.1% showed a very significant stimulatory effect on the percent of mitoses in the cell aggregates than in the control.
Analysis of variance made on the 24 hour mitotic percent data using an orthogonal contrast method indicated that the difference between the two nucleate treatments was not significant; but each was highly significantly different from the control.
At high concentrations of 0.5% or 1.0% DNAate in the medium, although the cells usually showed a complete cessation of mitoses in the beginning, after 4-5 days, the cell aggregates recovered revealing actively growing bud-like outgrowths from the original inoculum. Further incubation in these high concentrations did not appear to inhibit growth.
Cell aggregates growing in medium containing the nucleates or nucleic acid precursors (cytidine or uridine) also revealed an appreciably high incidence of polyploid cells in division. This was particularly pronounced in cell aggregates growing in medium containing DNA, DNAate, cytidine or uridine.
The present study thus reveals the heterogenity of cell types present in V. faba tissue cultures and the selective effect of growth factors on the mitotic pattern of different cell types. It is suggested that such evidences like stimulation of division in polyploid cells and recovery of mitotic activity following high concentrations of nucleic acid salts may be the result of certain stimuli brought out by the chemical additive incorporated in the culture medium. Specific cell types are thus stimulated to undergo division and express themselves as part of the cell population. The possibilities of using these techniques in studying interactions between the genetic potential of cells and the environment (chemical) to which they are exposed is suggested.
