Long noncoding RNA CCTT recruits CENP-C to centromeres by directly binding to centromeric DNA [ChIRP-Seq]

ABSTRACT: To investigate the exact locations of CCTT-chromatin interaction on a genome-wide scale, we modified previously reported ChIRP-seq (chromatin isolation by RNA purification followed by deep-sequencing) with a crosslinker 4’- aminomethyltrioxalen (AMT, a psoralen derivative), which allows fixation of nucleic acid interaction by ultraviolet light without crosslinking proteins. We designed 8 complementary DNA oligonucleotides that tiled the Alu-depleted part of CCTT. Affinity-purified CCTT-binding DNAs were sequenced and mapped to the HuRef genome hg38, which contains human α-satellite sequence models in each centromeric region. In contrast with 5.38% of input reads mapping to α-satellite sequence, 16.89% of CCTT-binding reads were enriched at α-satellites. Peaks bound by lnc-CCTT were identified by MACS2 algorithm, which compared the reads in CCTT-captured samples with that in input ones. CCTT-binding peaks mapped across the centromeric regions of all 23 reference centromeres. Next, we validated the enrichment of centromeric peaks located at all chromosomes via ChIRP-qPCR. To validate our ChIRP-seq results, we selected representatives of three major subpopulations: multimapping peaks in one specific chromosome and several chromosomes, as well as single-copy peaks. We performed ChIRP-qPCR and found abundant CCTT-binding centromeric peaks throughout all 23 chromosomes. Importantly, CCTT ChIRP-seq profile was highly correlated with the previously reported ChIP-seq profiles of CENP-C (Pearson correlation R = 0.82), both of which showed very strong, extensive signals across entire centromeric regions in HeLa cells.

ORGANISM(S): Homo sapiens

PROVIDER: GSE149532 | GEO | 2022/04/20

REPOSITORIES: GEO