The present invention relates to optimized systems for the genome editing of eukaryotic cells, preferably plant cells. Also provided is a plant delivery system comprising at least one Cpf1 enzyme, or a plant optimized construct encoding the same, to be synergistically combined with a Cpf1 guide RNA system. Further provided is a Cpf1 guide RNA system being flanked by a Hammerhead ribozyme sequence at the 5' end and by a plant-derived Hepatitis Delta Virus (HDV)-like ribozyme sequence at the 3' end, or being embedded within a coding or non-coding region, of a sequence encoding a frame sequence. Novel plant-derived HDV-like ribozyme sequences are also provided. Further provided are methods for improved genome editing, and the use of the various systems provided herein to obtain transformed plants, plant cells, tissues, organs, or a progeny thereof, or a plant material, modified in a targeted way even at difficult to access target sites.
