Article

CPEB: a life in translation

Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
Trends in Biochemical Sciences (Impact Factor: 13.52). 07/2007; 32(6):279-85. DOI: 10.1016/j.tibs.2007.04.004
Source: PubMed

ABSTRACT Nearly two decades ago, Xenopus oocytes were found to contain mRNAs harboring a small sequence in their 3' untranslated regions that control cytoplasmic polyadenylation and translational activation during development. This cytoplasmic polyadenylation element (CPE) is the binding platform for CPE-binding protein (CPEB), which promotes polyadenylation-induced translation. Since then, the biochemistry and biology of CPEB has grown rather substantially: mechanistically, CPEB nucleates a complex of factors that regulates poly(A) elongation through, of all things, a deadenylating enzyme; biologically, CPEB mediates many processes including germ-cell development, cell division and cellular senescence, and synaptic plasticity and learning and memory. These observations underscore the growing complexities of CPEB involvement in cell function.

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    • "PAPD1 was also reported to uridylate histone mRNA along with PAPD5 to target it for degradation [123] although the actual PAP that uridylates histone mRNA is somewhat controversial [124]. hGLD2 (PAPD4) is a cytoplasmic PAP that polyadenylates short (A)-tailed mRNAs in the cytoplasm [125] [126] and is involved in diverse functions such as embryonic development, cell cycle, germline maturation, synaptic plasticity, learning and memory [126] [127] [128] [129] [130] [131]. hGLD2 also polyadenylates p53 mRNA in the cytoplasm [128] [132]. "
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    • "Apart from general regulators of eIF4E activity, eukaryotic cells also contain eIF4E-binding proteins that regulate translation of subsets of mRNAs. Among them, it is worth mentioning Cup in Drosophila, Maskin in oocytes of Xenopus laevis and Neuroguidin in neurons (for references see reviews by Darnell & Richter, 2012; Lasko, 2012; Richter, 2007). However, this mode of regulation requires the formation of complexes of eIF4E-binding proteins with additional protein factors which in turn recognize specific RNA-motives within 3 "
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    Critical Reviews in Biochemistry and Molecular Biology 02/2014; 49(2). DOI:10.3109/10409238.2014.887051 · 5.81 Impact Factor
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    • "An in silico analysis of this UTR fragment revealed the presence of a cytoplasmic polyadenylation element (CPE). Previous work has demonstrated that during oocyte maturation CPEs maintain maternal mRNAs in a dormant state and then release these mRNAs when required (Richter, 2007; Zhang and Sheets, 2009). Deletion of the CPE from the sox19b 3Ј UTR fragment abolished the polyadenylation from the 2-cell to 64-cell stages (Fig. 4C). "
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