 With Yahli Lorch, Kornberg showed that a nucleosome on a promoter prevents the initiation of transcription, leading to the recognition of a functional role for the nucleosome, which serves as a general gene repressor.Kornberg's research group at Stanford later succeeded in the development of a faithful transcription system from baker's yeast, a simple unicellular eukaryote, which they then used to isolate in a purified form all of the several dozen proteins required for the transcription process.Through the work of Kornberg and others, it has become clear that these protein components are remarkably conserved across the full spectrum of eukaryotes, from yeast to human cells.