Segert Julian A, Bulyk Martha L
Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Program in Biological and Biomedical Sciences, Harvard University, Cambridge, MA 02138, USA.
bioRxiv. 2025 Jan 13:2025.01.09.632211. doi: 10.1101/2025.01.09.632211.
Transcriptional silencers are -regulatory elements that downregulate the expression of target genes. Although thousands of silencers have been identified experimentally, a predictive chromatin signature of silencers has not been found. H4K20me1 previously was reported to be highly enriched among human silencers, but our reanalysis of those data using an appropriate background revealed that the enrichment is only marginal. We generated H4K20me1 ChIP-seq profiles in S2 cells, which similarly showed that H4K20me1 does not mark silencers and instead is associated with active transcription. Silencers remain a poorly annotated, difficult to predict class of -regulatory elements whose specific chromatin features remain to be identified.
转录沉默子是下调靶基因表达的调控元件。尽管通过实验已鉴定出数千个沉默子，但尚未发现沉默子的预测性染色质特征。先前有报道称H4K20me1在人类沉默子中高度富集，但我们使用适当背景对这些数据进行的重新分析表明，这种富集只是微不足道的。我们在S2细胞中生成了H4K20me1 ChIP-seq图谱，同样表明H4K20me1并不标记沉默子，而是与活跃转录相关。沉默子仍然是一类注释不佳、难以预测的调控元件，其特定的染色质特征仍有待确定。
