Co-localization of components of the protein-synthesizing machinery with the cytoskeleton in G0-arrested cells.

The distribution of eukaryotic elongation factor 2 (eEF-2) in G0-arrested fixed human skin diploid fibroblasts was studied by indirect immunofluorescent microscopy. It was found earlier that the main part of eEF-2 in cycling cells was located near the nucleus in the endoplasm (Gavrilova et al., 1987). It has been demonstrated here that the transition from proliferation to the G0 phase of the cell cycle leads to the distribution of eEF-2 mainly along the intermediate filaments and/or microtubules. Both in cycling and in G0-arrested fibroblasts a portion of eEF-2 is also co-localized with actin microfilament bundles. The reversion of the cells from the G0 phase to proliferation is accompanied by rearrangement of the actin cytoskeleton and reversal to the original pattern of eEF-2 distribution. It is likely that the different types of cytoskeleton in eukaryotic cells can be involved in organization of protein-synthesizing machinery.