ABSTRACT
This chapter discusses the elements of transcription networks and their dynamics. Transcription factors are designed to transit rapidly between active and inactive molecular states, at a rate that is modulated by a specific environmental signal. The activities of the transcription factors in a cell therefore can be considered an internal representation of the environment. The internal representation by a set of transcription factors is a compact description of the myriad factors in the environment. The interaction between transcription factors and genes is described by transcription networks. Transcription factors affect the transcription rate by binding specific sites in the promoters of the regulated genes. Transcription factor proteins are themselves encoded by genes, which are regulated by other transcription factors, which in turn may be regulated by yet other transcription factors, and so on. An additional remarkable property of transcription networks is the modularity of their components.
