The Smc5/6 complex counteracts R-loop formation at highly transcribed genes in cooperation with RNase H2

Area of Science:

• Molecular Biology
• Genetics
• Cell Biology

Background:

• R-loops are common RNA-DNA hybrid structures arising from transcription.
• Their accumulation can impact genome stability and health.
• Cellular mechanisms for R-loop resolution in eukaryotes are not fully understood.

Purpose of the Study:

• To investigate the role of the Smc5/6 complex in R-loop removal.
• To understand the cellular processes governing R-loop resolution in eukaryotes.

Main Methods:

• Analysis of budding yeast mutants lacking Smc5/6 complex function.
• Investigating synthetic interactions between Smc5/6 mutants and R-loop resolving enzymes.
• In vivo and in vitro assays to assess Smc5/6 complex activity on RNA-DNA hybrids and R-loop degradation.

Main Results:

• Smc5/6 complex is a key regulator of R-loop removal during gene transcription.
• Mutants deficient in Smc5/6 complex accumulate RNA-DNA hybrids.
• Smc5/6 complex acts on specific RNA-DNA structures and promotes RNase H2-mediated R-loop degradation.

Conclusions:

• The Smc5/6 complex plays a critical role in resolving potentially toxic R-loops.
• This function is essential for highly transcribed genes and telomeres.
• Reveals a novel mechanism for maintaining genome integrity by managing R-loop structures.