RNA-POLYMERASE-II TRANSCRIPTION AND THE FUNCTIONAL-ORGANIZATION OF THE MAMMALIAN-CELL NUCLEUS

The study of RNA pol II-mediated transcription regulation has been dom inated by molecular biological approaches, Although these methods cont inue to provide important insights, other approaches are required to i nsure against an oversimplified view of gene expression. Improvements in EM methods and the development of the confocal light microscope hav e provided alternative and complementary means of investigating gene r egulation. Information on the ''context'' in which cis- and trans-acti ng factors operate can be achieved with these techniques. As a result, the spatial compartmentalization of nuclear processes involved in tra nscriptional and post-transcriptional processing has received consider able attention.