Knockout-Moos

A knockout moss is a moss plant in which one or more genes have been specifically switched off by means of a targeted genetic modification, known as gene targeting (gene knockout). Through the loss of a specific gene, the knockout moss loses the property encoded by this gene. The function of the knocked-out gene can now be deduced from the loss. This scientific approach is known as reverse genetics, as its function can be elucidated on the basis of a gene. In classical genetics, on the other hand, one starts with a phenotype and searches for the mutated gene. Knockout mosses are important in basic biological research and in biotechnology.

The targeted modification or targeted silencing of genes is based on the integration of a short DNA strand at a precisely determinable position in the genome of the host cell. For this purpose, the piece of DNA must have been constructed in such a way that it is identical to the gene locus at both ends. This DNA is then integrated very efficiently via homologous recombination at this gene locus. Knockout mice are also produced according to this principle. So far, this method of gene targeting has only been established in plants in the moss Physcomitrella patens, as the efficiency of homologous recombination is several orders of magnitude higher here than in seed plants.