The purpose of stress granules might be to protect RNAs from harmful conditions, thus their appearance under stress The accumulation of RNAs into dense globules could keep them from reacting with harmful chemicals and safe-guard the information coded in their RNA sequence.
Stress granules might also function as a decision point for untranslated mRNAs. Molecules can go down one of three paths: further storage, degradation, or re-initiation of translation
The stress proteins that are the main component of stress granules in plant cells are molecular chaperones that sequester, protect, and possibly repair proteins that unfold during heat and other types of stress , Therefore any association of mRNAs with stress granules may simply be a side effect of the association of partially unfolded RNA-binding proteins with stress granules , similar to the association of mRNAs with proteasomes
Environmental stress triggers a series of signals which eventually lead to formation of stress granules. Early on, it involves phosphorylation of eukaryotic translation initiation factor eIF2α. Further downstream, prion-like aggregation of the protein TIA-1 leads to the formation of stress granules. The term prion-like is used because aggregation of TIA-1 is concentration dependent, inhibited by chaperones, and because the aggregates are resistant to proteases It has also been proposed that microtubules play a role in the formation of stress granules, maybe by transporting granule components. This hypothesis is based on the fact that disruption of microtubules with the chemical nocodazole blocks the appearance of the granules
Stress granules and processing bodies share RNA and protein components, both appear under stress, and can physically associate with one another. While stress granules are associated with mRNAs, processing bodies are thought to be places of mRNA degradation. It has been proposed that mRNAs selected for degradation are passed from stress granules to processing bodies
Researchers from University Medical Center provide details of new studies and findings in the area of respiratory syncytial viruses.(Report)
Jan 08, 2011; New research, 'Respiratory syncytial virus induces host RNA stress granules to facilitate viral replication,' is the subject of a...
Researchers at University of Arizona, Howard Hughes Medical Institute Have Published New Data on Development Research.
Jan 25, 2011; A report, 'Stress-specific composition, assembly and kinetics of stress granules in Saccharomyces cerevisiae,' is newly published...