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, ora
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 sequenceat 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.