Meiosis, which gives rise to an organism’s germ cells, is essential for sexual reproduction. During meiosis homologous chromosomes undergo recombination. This complex process involves numerous regulatory steps, likely including the Dbf4-dependent kinase (DDK). Perutz group leader Verena Jantsch-Plunger explains: “DDK is known for regulating numerous steps in yeast meiosis, but its role in animals remains totally obscure. We aim to establish a genetically accessible simple animal model system to study DDK’s role by using Caenorhabditis elegans.” Building on work by two Master’s students in the Jantsch lab, the project was developed in the frame of the Special Research Program “Meiosis”, led by Verena since 2022.
To execute the genetic code, DNA must first be transcribed into RNA molecules, which then serve as the instructions for synthesizing proteins. However, functional RNA molecules require more than just transcription – they undergo a wide array of post-transcriptional modifications, carried out by specific enzymes. The Martinez lab is studying the tRNA ligase complex, an enzyme required for the maturation of tRNAs in mammalian cells. Group leader Javier Martinez elaborates: “We discovered that a subunit of this ligase, called Ashwin (ASW), is important for transporting the tRNA ligase to the nucleus. However, when bound to a different protein complex, the tRNA ligase facilitates the export of RNA molecules to the cytoplasm.” The mechanistic, functional and structural details of ASW and its part in RNA processing is the focus of Javier’s project in collaboration with the Plaschka lab from the Institute of Molecular Pathology (IMP).