hDNA2 nuclease/helicase promotes centromeric DNA replication and genome stability

Area of Science:

• Molecular Biology
• Genetics
• Cell Biology

Background:

• DNA2 is a key nuclease/helicase involved in DNA replication and repair processes.
• Centromeres, with their unique DNA structures, pose challenges for replication fork progression.
• Understanding DNA2's role at centromeres is vital for comprehending genome stability.

Purpose of the Study:

• To investigate the role and mechanism of DNA2 in replicating centromeric DNA.
• To determine the functional importance of DNA2's nuclease and helicase activities at centromeres.
• To explore the therapeutic potential of targeting DNA2 in cancer.

Main Methods:

• Biochemical assays to assess DNA2's binding and enzymatic activities on centromeric DNA.
• Cellular studies using DNA2 knockout models and inhibitors.
• Analysis of DNA replication, cell cycle progression, and chromosomal integrity.

Main Results:

• DNA2 preferentially binds to centromeric DNA and its activities are essential for resolving replication obstacles.
• Impaired DNA2 function disrupts centromeric DNA replication, CENP-A deposition, and activates ATR checkpoints.
• DNA2 inhibition leads to cell cycle arrest, abnormal chromosome segregation, and synergistic cancer cell death with ATR inhibitors.

Conclusions:

• DNA2 plays a critical role in supporting the replication of challenging centromeric DNA sequences.
• Dysregulation of DNA2 at centromeres leads to genomic instability and activates DNA damage responses.
• Targeting DNA2, particularly in combination with ATR inhibitors, represents a promising therapeutic strategy for cancer treatment.