[Retinol transport into the cell nucleus in vitro]

The retinol interaction with intact cellular nuclei, nuclear envelope and chromatin was investigated. We have shown that the Cellular Retinol-Binding Protein (CRBP) plays a very important role in such interaction. Retinol can specifically interacts with nuclei, nuclear envelope and chromatin only when it presents as a complex with CRBP. The obtained data allowed us to suggest that the process of retinol delivery to hypothetical nuclear receptors include of at least the following stages: 1) specific binding with nuclear envelope; 2) penetration into nuclei; 3) specific binding with chromatin receptors. CRBP is a necessary component at all this stages. Also we show that CRBP has not a species or tissue specificity.