# Exploring the Role of the Processing Body in Plant Abiotic Stress Response
## 4 P-Body and Plant Stress Responses
### Response of P-Body to Cold or Heat Stress  
In plants, P-Bodies are more sensitive to temperature stress, particularly heat stress. The number and volume of P-Bodies increases significantly under heat treatment [17]. Under normal growth conditions, Arabidopsis DCP1 and DCP2 are dispersed in the cytoplasm, but when exposed to 40 \({}^{\circ}\)C heat treatment, they aggregate into P-Body-like granules within the cytoplasm. When the heat treatment was removed, the P-Bodies disassembled gradually and their components diffused evenly in the cytoplasm [59]. As in drought stress, under temperature stress, the conserved proteins of the P-Body aggregate into a complex with 5\({}^{\prime}\)\(\rightarrow\)3\({}^{\prime}\) mRNA degradation function. During heat treatment, the 5\({}^{\prime}\)-m7 Gpp protective structures of mRNAs that are not beneficial for heat adaptation are excised by the DCP1/2 complex [59]. The decapped mRNA is subsequently degraded by 5\({}^{\prime}\)\(\rightarrow\)3\({}^{\prime}\) exoribonuclease XRN4 [60]. It is worth noting that the content of the Decapping Protein (DCP) family in the _Arabidopsis_ P-Body changes with the different temperature treatments. During heat treatment, the content of DCP2 is higher than that of DCP1. While under cold conditions, the content of DCP1 is higher than that of DCP2 [59]. It implies a differential regulation of mRNA decapping processes in the P-Body depending on the type of temperature stress. Specifically, DCP2 may be more actively involved in mRNA degradation under heat stress, whereas DCP1 may play a more prominent role in mRNA decapping and degradation under cold stress conditions. [PERSON] et al. found that Dcp2p, Dhh1p, PGK1-U1A, and MFA2P-U1A mRNAs exit P-Bodies for translation in yeast when recovered from glucose deprivation to normal physiological conditions, proving that the P-Body has the function of storing mRNA [11]. Therefore, besides mRNA degradation, changes in DCP1 and DCP2 content may mean that they have the function of storing mRNA [59]. This facilitates the rapid translation of mRNAs required for plant growth to adapt to normal environments. In addition to mRNAs that are not beneficial for heat or cold adaptation, some aberrant or truncated mRNAs can also be degraded in the P-Body. Cold resistance could be enhanced in Arabidopsis by cold acclimation (CA). During CA, the transcripts induced by cold are translated into functional proteins which contributed to increasing the low-temperature tolerance. However, during the post-transcriptional regulation of mRNA, the occurrence rate of premature termination codons (PTCs) increased due to alternative splicing, generating aberrant mRNAs or truncated mRNAs. These mRNAs will be eventually degraded in the P-Body [61]. Besides P-Bodies, plants can form other membrane-less organelles (MLOs), such as stress granules (SGs) under heat stress [62, 63]. When _Arabidopsis_ was treated at 35 \({}^{\circ}\)C heat conditions for 70 s, SGs were fused with P-Bodies and the protein and mRNA exchanged frequently between them. The thermotolerance of plants is enhanced through both mRNA degradation and storage mechanisms [63]. Tudor Staphylococcal Nuclease (TSN) proteins are located in P-Body and SGs and are essential for the assembly of SGs and P-Body under heat-stress conditions [64]. Additionally, it can promote the decapping of mRNAs which are not conducive to heat stress tolerance [63, 64]. In _Arabidopsis_, the acetylation lowers the binding affinity (ALBA) proteins ALBA4, ALBA5, and ALBA6 located in P-Bodies and SGs and directly binds them to the mRNA of heat stress transcription factors (HSFs) under heat stress, recruiting them to SGs and P-Bodies to protect the mRNA from being degraded [28]. The TZF family protein \(Hu\)TZF3 is located in P-Body and SGs and plays regulatory roles at the post-transcriptional level, then reduces the levels of reactive oxygen species (ROS) generated in response to salt or heat stress to enhance tolerance in _Hylocreus polyrhizus_[65].