Without a License, or Accidents Waiting to Happen

Abstract

This is a memoir of circumstances that have shaped my life as a scientist, some of the questions that have excited my interest, and some of the people with whom I have shared that pursuit. I was introduced to transcription soon after the discovery of RNA polymerase and have been fascinated by questions relating to gene regulation since that time. My account touches on early experiments dealing with the ability of RNA polymerase to selectively transcribe its DNA template. Temporal programs of transcription that control the multiplication cycles of viruses (phages) and the precise mechanisms generating this regulation have been a continuing source of fascination and new challenges. A longtime interest in eukaryotic RNA polymerase III has centered on yeast and on the enumeration and properties of its transcription initiation factors, the architecture of its promoter complexes, and the mechanism of transcriptional initiation. These areas of research are widely regarded as separate, but to my thinking they have posed similar questions, and I have been unwilling or unable to abandon either one for the other. An additional interest in archaeal transcription can be seen as stemming naturally from this point of view.

An Introduction to Transcription and Gene Regulation

“…The in vitro synthesized T2 RNA was seen to be self-complementary; under conditions appropriate for nucleic acid strand (re)association, it formed a distinctive material, with characteristics expected for double-stranded RNA of complex sequence, including resistance to degradation by RNase A and denaturation (melting) at a sharply defined temperature (29). 1 Two experiments addressing the same question (whether only one strand of a gene serves as template for RNA synthesis) appeared to yield the same answer. Using the first highly purified and characterized RNA polymerase (from E. coli), Mike Chamberlin found transcription of the double-stranded (replicative intermediate) form of phage ⌽X174 DNA yielding RNA with a nucleotide composition corresponding to that of its template and not of the strand that is packaged in the mature virion (or its complement) (30); Masaki and Marie Hayashi, working with Sol Spiegelman, obtained the same result (31).…”

“…I never lost my fascination with the question, although it took more than twenty years to get to the start point of the experiments that would provide the long awaited answers and another five years to lay the groundwork of the current understanding of this chapter in the enzymology of gene regulation. I have written elsewhere about this pursuit (1) and what I currently understand about the topic (60).…”