On Tuesday, 28.01.2020, 5.15 pm
Neva Caliskan (Helmholtz-Institut für RNA-basierte Infektionsforschung, Würzburg), will give an SFB 902 lecture:
„Single-Molecule and Ensemble Analysis of Protein-mediated Frameshifting“.
Venue: Campus Riedberg, lecture hall: N260/3.13
Guests are welcome!
Three bases encoding for an amino acid seem to represent the universal feature of the genetic code, yet ribosomes have evolved to read the code in different ways by altering the triplet periodicity of the reading frame. This phenomenon is called programmed ribosome frameshifting (PRF). PRF requires specific cis-acting elements – a slippery site followed by a stable RNA structure. PRF efficiency is also affected by trans-acting factors, including proteins, miRNAs and metabolites. While the general mechanisms of PRF and the involvement of cis-acting elements in this process are well understood, the regulation of these events is still vastly understudied. Additionally, the interactions of these factors with the RNA and the translation machinery have not yet been completely understood. Recent advances in single-molecule techniques allow to study these events at the molecular level and thus unveil hitherto unrecognised details. In this study, we chose the encephalomyocarditis virus (EMCV) 2A protein as a model to study PRF regulation. The expression of this protein is essential for frameshifting on the EMCV mRNA, and inhibition of PRF leads to severely reduced virulence. We investigated the interplay of the 2A protein with its frameshifting-RNA target. To do so, we combined single-molecule techniques, such as optical tweezers and confocal microscopy, together with HPLC-MS and microscale thermophoresis (MST). We anticipate these assays to be a starting point in analysing the translational kinetics of frameshifting and its interplay by RNA binding factors. Furthermore, recent examples of identification of such factors indicate that they play a major role in PRF regulation and understanding their mode of action will certainly uncover new fundamental principles of RNA-based gene regulation.