The chromatin factor ROW cooperates with BEAF-32 in regulating long-range inducible genes

Area of Science:

• Chromatin biology
• Molecular genetics
• Gene regulation

Background:

• Insulator proteins at topological associated domain (TAD) boundaries organize chromatin and regulate transcription.
• The precise mechanisms by which long-range chromatin contacts influence transcriptional regulation remain incompletely understood.

Purpose of the Study:

• To investigate the role of relative-of-WOC (ROW) in long-range transcriptional regulation mediated by boundary element-associated factor of 32kD (BEAF-32).
• To elucidate the molecular interactions and mechanisms involved in ROW-mediated gene regulation at TAD boundaries.

Main Methods:

• Co-immunoprecipitation assays to detect protein interactions.
• Chromatin immunoprecipitation (ChIP) to identify binding sites.
• RNA interference (RNAi) for gene knockdown.
• High-throughput chromosome conformation capture (Hi-C) to analyze genome-wide interactions.

Main Results:

• ROW protein physically interacts with heterochromatin proteins (HP1b, HP1c) and the insulator protein BEAF-32 at TAD boundaries.
• ROW, via its AT-hook motifs, binds AT-rich sequences adjacent to BEAF-32 binding sites.
• Knockdown of ROW leads to downregulation of genes targeted by BEAF-32, including those indirectly bound by ROW.
• Hi-C data reveals long-range interactions between ROW-bound housekeeping gene promoters and indirectly ROW-bound developmental gene promoters.

Conclusions:

• ROW functions with BEAF-32 and HP1 proteins to regulate transcription of developmental and inducible genes through long-range chromatin interactions.
• The ROW complex plays a critical role in mediating long-range transcriptional control at TAD boundaries.