SFB 1309 Research Areas
Area A: Modifications on Nucleic Acids
Project A09 – Investigation of GpnN-capped RNAs from bacteria and mammalian cells
In bacteria, stress can induce the formation of dinucleoside polyphosphates, such as Np3N or Np4N. These structures resemble the eukaryotic 5′ cap and can be incorporated co-transcriptionally to yield NpnN-capped RNAs. In mammalian cells, there is evidence for mRNA recapping. However, methodology for direct isolation of Gp4N-capped and/or recapped RNAs is missing. In subproject 1, we will develop a method for isolation of RNAs with a Gp4N-cap and identification by next-generation sequencing. We will investigate on a transcriptome-wide level, which RNAs bear a Gp4N-cap in stressed and unstressed bacteria. The method will also be applied to mammalian cell lines, for which at least Ap4A-capped RNAs have been reported. In subproject 2, we aim to investigate the process of cytoplasmic recapping. We will make photocaged and stabilized versions of the recapping substrates to test reconstitution of the 5′ cap structure in vitro and in mammalian cells.
