NCBI Summary:
Decapping is a key step in general and regulated mRNA decay. The protein encoded by this gene is a decapping enzyme. This protein and another decapping enzyme form a decapping complex, which interacts with the nonsense-mediated decay factor hUpf1 and may be recruited to mRNAs containing premature termination codons. This protein also participates in the TGF-beta signaling pathway. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Feb 2014]
General function
RNA processing, RNA binding
Comment
P-Body Loss Is Concomitant with Formation of a Messenger RNA Storage Domain in Mouse Oocytes. Flemr M et al. In mammalian somatic cells, several pathways converge on deadenylation, decapping, and 5'-3' degradation in cytoplasmic foci known as P-bodies. Because controlled mRNA stability is essential for oocyte-to-zygote transition, we examined dynamics of P-body components in mouse oocytes. We report that oocyte growth is accompanied by loss of P-bodies and a sub-cortical accumulation of several RNA-binding proteins, including DDX6, CPEB, YBX2 (MSY2), and the exon junction complex. These proteins form transient, RNA-containing aggregates in fully-grown oocytes with a surrounded nucleolus chromatin configuration. These aggregates disperse during oocyte maturation, consistent with recruitment of maternal mRNAs that occurs during this time. In contrast, levels of DCP1A are low during oocyte growth and DCP1A does not co-localize with DDX6 in the sub-cortical aggregates. The amount of DCP1A markedly increases during meiosis, which correlates with the first wave of destabilization of maternal mRNAs. We propose that the cortex of growing oocytes serves an mRNA storage compartment, which contains a novel type of RNA granule related to P-bodies.
Cellular localization
Comment
Ovarian function
Oocyte maturation, Early embryo development
Comment
Maternally-Recruited DCP1A and DCP2 Contribute to Messenger RNA Degradation During Oocyte Maturation and Genome Activation in Mouse. Ma J et al. The oocyte-to-zygote transition entails transforming a highly differentiated oocyte into totipotent blastomeres and represents one of the earliest obstacles that must be successfully hurdled for continued development. Degradation of maternal mRNAs, which likely lies at the heart of this transition, is characterized by a transition from mRNA stability to instability during oocyte maturation. Although phosphorylation of the oocyte-specific RNA-binding protein MSY2 during maturation is implicated in making maternal mRNAs more susceptible to degradation, mechanisms underlying mRNA degradation during oocyte maturation remain poorly understood. We report that DCP1A and DCP2, proteins responsible for decapping mRNA, are encoded by maternal mRNAs recruited for translation during maturation via cytoplasmic polyadenylation elements located in their 3' UTRs. Both DCP1A and DCP2 are phosphorylated during maturation, with CDC2A being the kinase likely responsible for both, although MAPK may be involved in DCP1A phosphorylation. Inhibiting accumulation of DCP1A and DCP2 by RNAi or morpholinos not only decreases degradation of mRNAs during meiotic maturation but also transcription of the zygotic genome. The results indicate that maternally-recruited DCP1A and DCP2 are critical players in the transition from mRNA stability to instability during meiotic maturation and that proper degradation maternal mRNA degradation is successful to execute the oocyte-to-zygote transition./////Association of luteinizing hormone receptor (LHR) mRNA with its binding protein leads to decapping and degradation of the mRNA in the p bodies. Menon B et al. (2013) Luteinizing hormone receptor undergoes downregulation during preovulatory Luteinizing hormone surge through a post-transcriptional mechanism involving an RNA binding protein designated as LRBP. The present study examined the mechanism by which LRBP induces the degradation of Luteinizing hormone receptor mRNA, specifically the role of decapping of Luteinizing hormone receptor mRNA and the translocation of LRBP-bound Luteinizing hormone receptor mRNA to degradative machinery. Immunoprecipitation of the complex with the 5'cap structure antibody followed by real time PCR analysis showed progressive loss of capped Luteinizing hormone receptor mRNA during downregulation suggesting that Luteinizing hormone receptor mRNA undergoes decapping prior to degradation. RNA immunoprecipitation analysis confirmed dissociation of eukaryotic initiation factor 4E from the cap structure, a step required for decapping. Furthermore, RNA immunoprecipitation analysis using antibody against the p body marker protein, DCP1A showed that Luteinizing hormone receptor mRNA was associated with the p bodies, the cytoplasmic foci that contain RNA degradative enzymes and decapping complex. Immunohistochemical studies using antibodies against LRBP and DCP1A followed by confocal analysis showed colocalization of LRBP with DCP1A during downregulation. This was further confirmed by co-immunoprecipitation of LRBP with DCP1A. The association of LRBP and Luteinizing hormone receptor mRNA in the p bodies during downregulation was further confirmed by examining the association of a second p body component, rck/p54, using immunoprecipitation and RNA immunoprecipitation respectively. These data suggest that the association of LRBP with Luteinizing hormone receptor mRNA results in the translocation of the messenger ribonucleoprotein complex to the p bodies leading to decapping and degradation.//////////////////
Expression regulated by
Comment
Ovarian localization
Oocyte
Comment
Dcp1-Bodies in Mouse Oocytes. Swetloff A et al. Monitoring Editor: A. Gregory Matera Processing bodies (P-bodies) are cytoplasmic granules involved in the storage and degradation of mRNAs. In somatic cells, their formation involves miRNA-mediated mRNA silencing. Many P-body protein components are also found in germ cell granules, such as in mammalian spermatocytes. In fully grown mammalian oocytes, where changes in gene expression depend entirely on translational control, RNA granules have not as yet been characterized. Here we show the presence of P-body-like foci in mouse oocytes, as revealed by the presence of Dcp1a and the colocalization of RNA associated protein 55 (RAP55) and the DEAD box RNA helicase Rck/p54, two proteins associated with P-bodies and translational control. These P-body like structures have been called Dcp1-bodies and in meiotically-arrested primary oocytes, two types can be distinguished based upon their size. They also have different protein partners and sensitivities to the depletion of endogenous siRNA/miRNA and translational inhibitors. However, both type progressively disappear during in vitro meiotic maturation, and are virtually absent in metaphase II-arrested secondary oocytes. Moreover, this disassembly of hDcp1a-bodies is concomitant with the post-translational modification of EGFP-hDcp1a.