A double on the Rocs with a twist: Rocaglamide A targets multiple DEAD-box helicases to inhibit translation...

Area of Science:

• Biochemistry
• Molecular Biology
• Cancer Research

Background:

• Rocaglamide A (RocA) is a natural product with known biological activities.
• DEAD-box helicases are crucial for various cellular processes, including translation.
• Understanding RocA's molecular targets is key to its therapeutic potential.

Purpose of the Study:

• To identify novel protein targets of rocaglamide A.
• To investigate the mechanism by which RocA affects translation.
• To determine the role of specific DEAD-box helicases in cancer cell sensitivity to RocA.

Main Methods:

• Affinity purification coupled with mass spectrometry to identify RocA-binding proteins.
• Biochemical assays to assess the effect of RocA on helicase activity.
• Western blotting and cell viability assays to correlate protein levels with drug sensitivity.

Main Results:

• Chen et al. identified eukaryotic initiation factor 4A2 (eIF4A2) and DEAD-box helicase 3 X-linked (DDX3X) as novel targets of RocA.
• RocA treatment converts these DEAD-box helicases into dominant-negative translation repressors.
• Cancer cell sensitivity to RocA was found to be directly dependent on the expression levels of eIF4A2 and DDX3X.

Conclusions:

• RocA's target spectrum is expanded to include eIF4A2 and DDX3X.
• The findings provide a mechanistic link between RocA, translation regulation, and cancer cell fate.
• Expression levels of eIF4A2 and DDX3X may serve as biomarkers for RocA efficacy in cancer therapy.