Chromatin texture analysis in living cells.

In recent years, there has been an increasing interest in applications of fluorescence measurements to studies on many physiological mechanisms in living cells. However, few studies have taken advantage of DNA quantification by fluorometry for dynamic assessment of chromatin organization. This type of approach involves both optimal conditions for DNA staining and the use of image cytometry. In this context, this report describes the application of an internal grey-level segmentation method for the assessment of real time modifications of chromatin organization in living cells. These developments are based on a specific, stoichiometric method for nuclear DNA content measurement. Preliminary data obtained from Hela cells suggests the possibility of following variations of nuclear texture (heterogeneity, granularity, condensation, radial distribution) related to the cell cycle progression of cells that are maintained alive.