Flow cytofluorimetric determination of protein distribution throughout the cell cycle.

Quantitative treatment of multiparametric determination on cells using flow cytofluorometry was made possible by the development of a computer program that allows the relative quantification of a specific protein as a function of the position of cells during the cell cycle. This type of analysis provides interesting information about the distribution of a given protein throughout the cell cycle. Four examples showing the distribution of specific proteins illustrate such a quantification during the cell cycle in two different cell lines. The program also allows for the handling of a series of histograms obtained by the analysis of protein distribution as a function of DNA content in relation to a third parameter. To illustrate possible applications for this program, the evolution of the distribution of two proteins, the oncoprotein p53 and the histone H1(0), during the induced differentiation of murine erythroleukemia cells has been studied.