DNA Damage Response: Key Cellular Mechanism Uncovered

Why in news :

A recent Indo-French study (Indian Institute of Science and Institut Curie, Paris) published in EMBO Reports has uncovered a new layer of regulation in cellular DNA damage response, relevant for understanding cellular stress adaptation, cancer biology, and neurodegenerative disease mechanisms.

Key Points :

1. DNA Damage and Cellular Response:

• DNA damage can occur due to UV radiation, chemicals, or copying errors.

• Cells activate repair mechanisms by producing specific repair proteins.

2. New Finding – Regulating Repair Protein Levels:

• The study shows that cells temporarily suppress mRNA translation for certain repair genes to avoid overproduction.

• This ensures optimal repair and prevents harmful over-repair or error-prone repair.

3. Key Proteins Identified:

• Scd6 in yeast and LSM14A in human cells.

• These proteins form RNA granules during stress (e.g., hydroxyurea treatment).

• These granules temporarily trap mRNA, such as that for the DNA-repair enzyme Srs2, thus slowing protein synthesis.

4. Scientific Significance:

• RNA granules act as reversible storage — not degradation sites.

• This mechanism is evolutionarily conserved and contributes to cell survival during genotoxic stress.

5. Applications:

• Cancer Therapy: Targeting RNA granule dynamics could disrupt stress adaptation in cancer cells, making them more vulnerable to chemotherapy.

• Neurodegeneration: Insights could help understand protein misregulation and stress adaptation in diseases like ALS or Alzheimer’s.