Abstract

In the beginning of the genome era regulatory genomics mainly addressed the level of transcription. In recent years part of the attention starts to shift towards regulation at the post-transcriptional level, mainly to further stages in RNA metabolism and to translation. A notion that begins to appear with such recent studies is that the various levels of propagation of genetic information are often coupled to one another, such that activity at one level, such as transcription, might affect others, e.g. mRNA decay or translation. In this talk I will discuss our recent attempts to understand the structure of genome-wide regulatory networks that control post-transcription gene expression and the modes of their regulatory coupling. I will focus on two recent studies, in the first we investigate a regulatory coupling between transcription and mRNA degradation. In this context I will discuss the intriguing possibility that during transcription of a gene the half life of its mRNA is already determined. In a second part of the talk I will describe our investigations of regulatory sequences that control translation efficiencies, and suggest a universal novel design of coding sequences that supports optimal translation, and that affects as a consequence mRNA decay rates.