RNA Granules

Stress granules are linked to translation arrest but are not required to cause translation arrest. Stress granules and P-bodies are described as dynamic compartments for translationally inactive mRNAs. Stress granules contain stalled preinitiation complexes, RNA-binding proteins, selected initiation factors, and 40S subunits, but lack eIF5 and eIF2. P-bodies contain repression and decay machinery and can store mRNAs without immediate degradation. Stress granule assembly is often downstream of eIF2α phosphorylation and is driven by RNA-RNA, protein-RNA, and protein-protein interactions.