RTEL1 Regulates G4/R-Loops to Avert Replication-Transcription Collisions

Area of Science:

• Molecular Biology
• Genetics
• Cell Biology

Background:

• Regulator of telomere length 1 (RTEL1) is crucial for telomere maintenance and DNA replication.
• The origins of replication stress in RTEL1-deficient cells are not fully understood.

Purpose of the Study:

• To investigate the role of RTEL1 in maintaining transcriptional and replication integrity.
• To elucidate the molecular mechanisms underlying replication stress in RTEL1-deficient cells.

Main Methods:

• Analysis of transcriptional changes in Rtel1-deficient cells.
• Investigating the role of G-quadruplex (G4)-DNA structures.
• Assessing R-loop formation and transcription-replication collisions (TRCs).
• Utilizing RNaseH1 overexpression to resolve R-loops.

Main Results:

• Loss of RTEL1 leads to extensive transcriptional alterations, particularly in genes with G-quadruplex sequences.
• RTEL1 deficiency results in increased R-loops and transcription-replication collisions.
• Resolving R-loops via RNaseH1 overexpression suppresses TRCs and rescues replication defects.

Conclusions:

• RTEL1 unwinds G-quadruplex DNA/RNA-DNA hybrids to prevent transcription-replication collisions.
• This function of RTEL1 is critical for preventing global deregulation of transcription and DNA replication.