Dealing with new neighbours: Keeping genes active after transposon insertion
The group of Falk Butter at the Institute of Molecular Biology (IMB) in Mainz, Germany, in collaboration with the group of Steven Jacobsen from the University of California Los Angeles (UCLA), have discovered how cells prevent the accidental silencing of critical genes.
In an article published today in Science, they describe how a group of proteins protect genes from the silencing effects of nearby transposable elements. This research highlights how an epigenetic modification, DNA methylation, which usually silences genes, can limit the detrimental effects of transposons, or “jumping genes”. The variation in the response to DNA methylation allows transposons to remain in the genome as a source of evolutionary diversity, while also being used to enhance the expression of nearby genes. The research is another step in understanding the puzzle of how evolution has let so many of these elements become critical features in the DNA of most organisms but still managed to avoid their nastier side effects.