What is the difference between P-bodies and stress granules?
While P-bodies (PBs) assemble around the key enzymes of cytoplasmic RNA degradation, stress granules (SGs) assemble around essential components of the translation machinery.
What is the role of P-bodies?
Processing bodies (P-bodies) are cytoplasmic ribonucleoprotein (RNP) granules primarily composed of translationally repressed mRNAs and proteins related to mRNA decay, suggesting roles in post-transcriptional regulation. P-bodies are conserved in eukaryotic cells and exhibit properties of liquid droplets.
How does mRNA degradation affect translation?
Another set of studies has suggested that mRNA degradation occurs on translating mRNA and that mRNA decay factors can inhibit translational elongation as well as affect mRNA degradation. These defects feed into the quality control of translational processes, such as Nonsense-Mediated (NMD), Non-Stop, and No-Go decay.
What inhibits mRNA degradation?
Degradation of both mRNAs was strongly inhibited in cells exposed to UV-B light. UV light also inhibited deadenylation and degradation of endogenous mRNA of the chemoattractant cytokine interleukin (IL)-8. Both effects occurred rapidly and independently of newly induced genes.
What do stress granules do?
Stress granules contain non-translating mRNAs, translation initiation components, and many additional proteins affecting mRNA function. Stress granules have been proposed to affect mRNA translation and stability, as well as being linked to apoptosis and nuclear processes.
How do P bodies form?
P bodies have been suggested to form predominantly through interactions of Edc3 and a prion-like domain on Lsm4. In this work, we provide evidence that P-body assembly can be driven by multiple different protein-protein and/or protein-RNA interactions, including interactions involving Dhh1, Psp2, and Pby1.
Why is mRNA degradation important?
While cells degrade messenger RNA to regulate the amount of proteins that can be translated from each mRNA molecule, they also modify mRNA molecules in a way that increases the stability of the molecule and increases the protein output under specific conditions and at certain times.
What is meant by mRNA degradation?
MRNA degradation is a process to eliminate mRNA that is either no longer required in the cell or has aberrant features. Subsequently, the 5′ cap of the mRNA is removed by the DCP1-DCP2 decapping complex. Following cap removal, the mRNA is degraded by the XRN1 exoribonuclease in a 5′ to 3′ direction.
What determines mRNA degradation?
Sequences within the mRNA, such as AU-rich elements, can determine the rate of decay under various conditions. RNA-binding proteins recognize sequence elements and modulate the rate of decay, some by recruiting the decay machinery, others by remodelling the conformation of messenger ribonucleoprotein.
What are RNA stress granules?
Stress granules are dense aggregations in the cytosol composed of proteins and RNAs that appear when the cell is under stress. The RNA molecules stored are stalled translation pre-initiation complexes: failed attempts to make protein from mRNA. Note that there are also nuclear stress granules.
What marker proteins are found in P-bodies?
P-bodies are constitutively associated with proteins that are involved in translational repression and mRNA decay. These proteins include cytoplasmic deadenylase complex, decapping coactivator and enzyme, decapping activators, and 5′-3′ exoribonuclease.