A review of transgenerational epigenetics for RNAi, longevity, germline maintenance and olfactory imprinting in Caenorhabditis elegans

Inheritance of acquired characteristics without changes in DNA sequence has been called transgenerational epigenetics. This review looks at studies that used the model system Caenorhabditis elegans to uncover mechanisms of transgenerational epigenetics in studies of RNA interference, studies of longevity, studies of germline continuity and a study on olfactory imprinting. In each case, researchers have uncovered critical roles for small RNAs and for Argonaute proteins. They have revealed several different genetic pathways that mediate RNA silencing of foreign RNA for a few or for many generations, as well as identifying a related pathway responsible for recognized self-generated RNAs. Together, these studies have greatly advanced our understanding of trangenerational epigenetics.