A small RNA-based innate immune system guards germ cell genomes

One of the most fundamental biological imperatives is faithful transmission of the genome from parent to progeny. Transposons - parasitic mobile genetic elements - threaten this process and represent one of the most pervasive embodiments of the host-parasite relationship. Their drive is to propagate in germ cells; failure to control these elements can lead to sterility. Professor Hannon discovered the piRNA pathway, a small RNA-based innate immune system that recognises and silences transposons in germ cells. He will use this award to study the action mechanism of piRNAs. Specifically, he will investigate how maternally-inherited piRNA populations in drosophila influence transposon silencing in germ and somatic cells, how piRNAs are processed, and establish how they bring about long-term transcriptional repression.