As part of the SFB 740 we aim to determine the mechanism by which eS6 phosphorylation influences target-mRNA selection of ribosomes. As further reaching hypothesis we will probe if and how translation is governed by eS6-tail modification patterns (or a simple on/off mechanism), i.e. if there is a ribosomal equivalent to CTD control of transcription or the histone code hypothesis. This would highlight a similarity of regulation between translation and transcription and have huge impact on our understanding of translational control. Moreover, with quantitative cross-linking/mass spectrometry (CLMS) and high-resolution CLMS we introduce technologies to protein assemblies that will allow probing a broad range of mechanistic questions in other research projects of this consortium, specifically Project A4, M. Wahl, Project B5, T. Sommer and Project C7, O. Daumke.