Genetic Tools Development

Novel Strategies for Gene Editing and Gene Therapy

The advent of easily programmable nucleases, like TALEN and CRISPR/Cas9, enables us to edit the genome of different organisms directly in a fast and efficient manner. Based on this, we utilize the CRISPR/Cas9 system also for translational approaches e.g. for the genetic modification of patient-derived cell lines like fibroblasts and hiPS lines. Beyond this, CRISPR/Cas9 enables new roads for gene therapy approaches e.g. as an ex vivo gene therapy method and to treat human genetic diseases. However, the culture and reprogramming of hiPS derived from patients is still a laborious and tedious process. Therefore, our team also investigates alternative ways to target and modify the genome in vivo using viral vectors and novel strategies of boosting the homologous recombination rate, which is vital both for model generation as well as for many therapeutic approaches. As a further innovative tool for this purpose, we developed a split-Cas9 system based on separated N- and C-terminal part of the Cas9 nuclease that can be efficiently reconstituted by intein-mediated trans-splicing. Nevertheless, Cas9 is not limited to induce double strand breaks, it can be used as a universal tool to guide Elements to distinct regions of the DNA. In this regard, we utilize the CRISPR/Cas9-system for targeted gene induction in vitro as well as ex vivo. This Cas9 transcriptional activator system is a versatile tool for various applications.