RNA-Degrading Exosome Complexes: Molecular Mechanisms and Structural Insights.

Area of Science:

• Molecular Biology
• Cell Biology
• Biochemistry

Background:

• The RNA exosome is a crucial multiprotein complex for 3'-to-5' RNA degradation in eukaryotes.
• It operates in both the cytoplasm (mRNA surveillance/decay) and nucleus/nucleolus (cryptic RNA degradation, RNA trimming).
• A network of cofactors and RNA helicases interacts with the exosome core to regulate substrate processing.

Purpose of the Study:

• To review the mechanistic principles of the RNA exosome complex.
• To integrate findings from various analyses into a comprehensive understanding of exosome function.
• To illustrate the dynamic nature of the exosome in RNA processing and decay.

Main Methods:

• Genetic analyses
• Cellular analyses
• Biochemical analyses
• Structural analyses

Main Results:

• The exosome core is surrounded by regulatory cofactors and RNA helicases.
• Substrate features and the cofactor network dictate degradation pathways.
• Molecular movies visualize the dynamic action of the exosome.

Conclusions:

• The RNA exosome is a versatile machine essential for RNA homeostasis.
• Its function is finely tuned by accessory factors and substrate characteristics.
• Understanding the exosome provides insights into RNA processing and decay pathways.