Transcriptional competence defines the heterochromatin nucleating potential of isolated MSR units - PubMed
4 hours ago
- #heterochromatin
- #MSR
- #transcription
- Transcriptional competence determines heterochromatin nucleation at major satellite repeats (MSR) in mouse ES cells.
- Heterochromatin forms only at transcriptionally competent MSR units among >18,000 copies examined.
- Insertion of three or more intact MSR units into an inert genomic region induces heterochromatic marks, HP1 recruitment, and histone H1 incorporation.
- Only transcriptionally competent MSR units, not permutated variants or LINE1 5'UTR elements, nucleate de novo heterochromatin.
- MSR-derived transcription is bi-directional and attenuated by the Integrator complex associated with RNAPII.
- Multi-copy intact MSR units facilitate RNAPII engagement by unwinding the DNA template.
- The study reveals a transcription-coupled mechanism for heterochromatin nucleation based on DNA/RNA logic.