COMPARING TRANSCRIPTIONAL INITIATION BY RNA-POLYMERASE-I AND RNA-POLYMERASE-III

We comment on the current understanding of transcriptional initiation by RNA polymerases I and III, and look for common modes of operation of these enzymes, emphasizing selected recent developments. These include definitive experiments on the constitution of the human RNA polymerasel transcription factor SL1/TIF-IB, the development of a genetic system for analyzing the function of RNA polymerasel in yeast, the elucidation of the structure of the human snRNA gene transcription factor SNAP(c), and initial stages of mapping the protein-protein interactions involved in the assembly of transcriptional initiation complexes.