A post-translational modification code for transcription factors: sorting through a sea of signals

It is proposed that a PTM code is not only possible but necessary in the context of transcription factors regulating multiple processes and should both provide a further layer of information integration from several transduction pathways and warrant highly specific cellular outputs.

Abstract

Cellular responses to environmental or physiological cues rely on transduction pathways that must ensure discrimination between different signals. These cascades 'crosstalk' and lead to a combinatorial regulation. This often results in different combinations of post-translational modifications (PTMs) on target proteins, which might act as a molecular barcode. Although appealing, the idea of the existence of such a code for transcription factors is debated. Using general arguments and recent evidence, we propose that a PTM code is not only possible but necessary in the context of transcription factors regulating multiple processes. Thus, the coding potential of PTM combinations should both provide a further layer of information integration from several transduction pathways and warrant highly specific cellular outputs.