PIWI-interacting RNAs (piRNAs)
PIWI-interacting RNAs (piRNAs) are a class of small non-coding RNAs that guide Argonaute proteins to their targets. The main function of the piRNA pathway is to control transposable elements, either through the piRNA-guided cleavage of their mRNAs in the cytoplasm or through piRNA-guided establishment of repressive chromatin at the site of their nascent transcription in the nucleus. A major question in the field is how these piRNAs are derived to selectively recognise transposon transcripts, given that the piRNA-guided silencing can only recognise complementary RNA.
Together with the Hannon lab, we are involved in various projects to enhance our understanding of piRNA-guided transposon silencing. One active area of research is to explore the potential for deep learning methods to extend our previous work, which established a sequence motif for piRNA precursor cleavage (Bornelöv et al., 2022). We are also using evolutionary approaches, such as our recent work to identify unistrand piRNA clusters across the Drosophila genus (van Lopik et al., 2023) and are developing automated algorithms for cluster identification.
We are currently working with the Hannon lab in this area. This is expected to continue also during 2024-2032 thanks to generous funding from Wellcome Trust to Greg Hannon, Ben Nicholson and Susanne Bornelöv.