Dcp2, the major mRNA decapping enzyme in eukaryotic cells, is crucial for regulating cellular mRNA levels. Eukaryotic mRNAs have a 5' cap structure, and Dcp2-by removing this cap-shuts down translation and primes mRNA for degradation. Its activity is regulated by interactions with activators like Dcp1, Edc1, and Edc3, as well as an autoinhibition mechanism [1,7].

In human cells, MOV10 recruits DCP2 to LINE-1 RNA, forming a complex with liquid-liquid phase separation properties. This cooperation leads to LINE-1 RNA decapping, degradation, and reduced retrotransposition, identifying DCP2 as a key effector in LINE-1 replication [2]. In small cell lung cancer, METTL3 promotes chemoresistance by inducing mitophagy. METTL3 causes m6A methylation of DCP2, leading to its degradation, which in turn promotes mitochondrial autophagy through the Pink1-Parkin pathway [3]. In chronic cerebral ischemia, Dcp2 is upregulated, and its silencing inhibits apoptosis of oxygen glucose deprivation-treated HT22 cells. Dcp2 also promotes RNCR3 expression, which is part of an axis regulating neuronal apoptosis [4]. In yeast, Dcp2 C-terminal cis-binding elements control the formation of distinct decapping complexes, determining substrate specificity [5]. In yeast dcp2Δ cells, hundreds of mRNAs increase in abundance due to impaired decapping, and there are widespread changes in translation efficiency, affecting metabolism and filamentation [6].

In conclusion, Dcp2 is essential for mRNA decapping and subsequent degradation, thereby regulating gene expression. Its dysregulation is implicated in various disease conditions such as LINE-1-related genetic instability, small cell lung cancer chemoresistance, and neuronal apoptosis in chronic cerebral ischemia. Understanding Dcp2 through genetic models helps reveal its functions in these biological processes and disease mechanisms, potentially guiding the development of therapeutic strategies.

References:

1. Wurm, Jan Philip, Sprangers, Remco. 2019. Dcp2: an mRNA decapping enzyme that adopts many different shapes and forms. In Current opinion in structural biology, 59, 115-123. doi:10.1016/j.sbi.2019.07.009. https://pubmed.ncbi.nlm.nih.gov/31473440/

2. Liu, Qian, Yi, Dongrong, Ding, Jiwei, Peng, Xiaozhong, Cen, Shan. 2023. MOV10 recruits DCP2 to decap human LINE-1 RNA by forming large cytoplasmic granules with phase separation properties. In EMBO reports, 24, e56512. doi:10.15252/embr.202256512. https://pubmed.ncbi.nlm.nih.gov/37437058/

3. Sun, Yueqin, Shen, Weitao, Hu, Shulu, Zhu, Weiliang, Zhang, Jian. 2023. METTL3 promotes chemoresistance in small cell lung cancer by inducing mitophagy. In Journal of experimental & clinical cancer research : CR, 42, 65. doi:10.1186/s13046-023-02638-9. https://pubmed.ncbi.nlm.nih.gov/36932427/

4. Yang, Jin, Liu, Xiaobai, Zhao, Yubo, Cui, Zheng, Liu, Yunhui. 2023. Mechanism of Dcp2/RNCR3/Dkc1/Snora62 axis regulating neuronal apoptosis in chronic cerebral ischemia. In Cell biology and toxicology, 39, 2881-2898. doi:10.1007/s10565-023-09807-8. https://pubmed.ncbi.nlm.nih.gov/37097350/

5. He, Feng, Wu, Chan, Jacobson, Allan. 2022. Dcp2 C-terminal cis-binding elements control selective targeting of the decapping enzyme by forming distinct decapping complexes. In eLife, 11, . doi:10.7554/eLife.74410. https://pubmed.ncbi.nlm.nih.gov/35604319/

6. Vijjamarri, Anil Kumar, Niu, Xiao, Vandermeulen, Matthew D, Lin, Zhenguo, Hinnebusch, Alan G. 2023. Decapping factor Dcp2 controls mRNA abundance and translation to adjust metabolism and filamentation to nutrient availability. In bioRxiv : the preprint server for biology, , . doi:10.1101/2023.01.05.522830. https://pubmed.ncbi.nlm.nih.gov/36711592/

7. Valkov, Eugene, Muthukumar, Sowndarya, Chang, Chung-Te, Weichenrieder, Oliver, Izaurralde, Elisa. 2016. Structure of the Dcp2-Dcp1 mRNA-decapping complex in the activated conformation. In Nature structural & molecular biology, 23, 574-9. doi:10.1038/nsmb.3232. https://pubmed.ncbi.nlm.nih.gov/27183195/