Research in the Sullivan lab focuses on the genetics and epigenetics of the centromere, a chromosomal region vital for maintaining genomic stability. Human centromeres are assembled on repetitive alpha satellite DNA arrays that span multiple megabases and are organized into CEN chromatin, a distinct type of chromatin containing marks of active transcription. My research explores the non-coding RNAs produced from the repetitive alpha satellite DNA underlying centromeres, with a particular focus on defining the differences and similarities between alpha satellite transcripts produced from different chromosomes, as well as their overall role in centromere function. Although alpha satellite arrays on all chromosomes produce non-coding RNAs, we have discovered that each array produces distinct transcripts that are localized to the centromere in cis and stably associated with the chromosome throughout the cell cycle. An improved understanding of this unique class of non-coding RNA will shed light on how centromeres are formed, maintained, and, in some cases, inactivated to ensure chromosome stability.
(Figure Legend) Alpha satellite RNA (green) localizes to the centromere (visible here as a constriction point) of every human metaphase chromosome (blue).