Subnuclear dynamics and transcription factor function.

At a simplistic level, the nucleus can be thought of as singular organelle with a nuclear envelope designed to isolate the biochemical reactions required for gene transcription and DNA replication from the cytoplasm. It has become increasingly clear, however, that many higher levels of organization exist within the nucleus. A functional consequence of this organization is that nuclear processes that include transcription, RNA processing, and DNA synthesis are isolated to specific intranuclear domains to ensure efficiency. With the advent of GFP technologies and increasingly sophisticated instrumentation, we have continued to dissect the relationship between organization and function, in particular using live cells and ligand-dependent steroid receptors as a model system. These new opportunities have provided further insight into receptor function and the dependence upon intranuclear dynamics that take place within minutes of hormone addition. J. Cell. Biochem. Suppl. 35:99-106, 2000.