The role of ncRNA in centromeres: a lesson from marsupials

Though centromeres have been thought to be comprised of repetitive, transcriptionally inactive DNA, new evidence suggests that eukaryotic centromeres produce a variety of transcripts and that RNA is essential for centromere competence. It has been proposed that centromere satellite transcripts play an essential role in centromere function through demarcation of the kinetochore-binding domain. However, the regional limits and regulation of transcription within the mammalian centromere are unknown. Analysis of transcriptional domains within the centromere in mammalian models is impeded by the unbridgeable expanse of satellite monomers throughout the pericentromere. The comparatively small size of the wallaby centromere and the evolutionary role of the centromere in marsupial speciation events position the wallaby centromere as a tractable and valuable mammalian centromere model. We highlight the current understanding of the wallaby centromere and the role of transcription in centromere function.