Research Summary
The paper presents a characterization of processed and functionally important lncRNAs deriving from human centromeres that bind the centromeric histone variant CENP-A. A RIP-seq library targeting CENP-A provided sequence reads that were used to construct 432 transcripts of heterogeneous length (300-2500 bases). These transcripts mapped confidently to almost every human chromosome, are enriched in 𝛼-satellite repeats, and are unique enough to permit separation into four classes through two different clustering methods. Visualizing a subset of these transcripts via RNA FISH in synchronized HeLa cells revealed that multiple and unique 𝛼-satellite-containing RNAs are present in the cell nucleus, and that individual cenRNAs (eg. cenRNA#4) can be localized near one centromere via co-IF with centromere protein B (CENP-B) in a fraction of cells. Both 𝛼-satellite-containing RNAs and cenRNA#4 are likely polyadenylated as they can be amplified from cDNA using poly-dT primers. Finally, siRNA-knockdown of 𝛼-satellite RNAs or cenRNA#4 individually resulted in a higher rate of chromosomal segregation defects compared to a scrambled siRNA target, lending support to a functional role of these transcripts in maintaining chromosome stability.