Visualization of Chromatin Arrangement in Giant Nuclei of Mouse Trophoblast by Videomicroscopy and Laser Scanning Microscopy

Abstract

In the past years substantial progress has been made in the development of novel light microscopic (LM) instrumentation, which provided new insight in structure and dynamics of nuclear chromatin organization. (i) High resolution videomicroscopy allowed investigations on cellular structures which could previously only be demonstrated by electron microscopic (EM) techniques and therefore were largely inaccessible to light microscopy (Allen, 1985; Trendelenburg et al., 1986). (ii) More recently, laser scanning microscopy (LSM) has allowed us to get insight into the very complex organization of intact cells. Using the confocal scanning mode it is possible to record series of consecutive optical sections through thick specimens. These image stacks can then be further processed for 3-D visualization and 3-D reconstruction (Ploem, 1987; White et al., 1987; Montag et al., 1989a). Therefore, videomicroscopy and confocal laser scanning microscopy can be applied for the examination of large numbers of samples and yield a high amount of structural as well as spatial information in a relatively short time, as compared to the conventional approach using serial thin section electron microscopy.