Areas of Interest
Heterochromatin establishment is crucial for genome stability, centromere function and transposon control. Small RNA dependent silencing pathways are highly conserved and play important roles in transposon silencing in flies and mammals. In fission yeast, small RNAs are critically involved in localizing histone modifying enzymes to sites of heterochromatin formation. The pericentromeric repeats produce long non-coding RNAs that serve as scaffolds to recruit the small RNA binding protein Argonaute to sites of heterochromatin formation. Small RNA production, which depends on transcription and processing of long non-coding RNAs, must then also be coordinated with epigenetic silencing, which abrogates their transcription. The conflict between these two processes presents a paradox that has yet to be definitively answered. In my work, I use real-time single cell imaging and fission yeast genetics to visualize the order and timing of assembly of individual components that are involved in RNAi mediated heterochromatin formation.