External Seminar Christian FROEKJAER-JENSEN

In some cases genetic “memories” are transmitted across generations without changes in DNA sequences. This type of memory is referred to as transgenerational epigenetic inheritance and can be mediated by small RNA populations and changes to chromatin. Epigenetic inheritance is probably best understood at the molecular level in the nematode C. elegans due to their short life-span and easy genetics. Here, I will describe a novel method for silencing genes in germ cells and early development using a class of small RNAs (piRNAs). We have used this silencing system to determine conditions where memories are inherited for a few generations (typically, three to six generations) and conditions where the memory becomes essentially permanent.