Distinct expression patterns of the subunits of the CCR4-NOT deadenylase complex during neural development

Division of Oncology, Department of Cancer Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 07/2011; 411(2):360-4. DOI: 10.1016/j.bbrc.2011.06.148
Source: PubMed

ABSTRACT The stability of mRNA influences the dynamics of gene expression. The mammalian CCR4-NOT complex is associated with deadenylase activity, which shortens the mRNA poly(A) tail and thereby contributes to destabilization of mRNAs. The complex consists of at least nine subunits and predominantly forms a 2.0MDa protein complex in HeLa cells. Accumulating evidence suggests that the CCR4-NOT complex is involved in cell growth and survival; however, the regulatory mechanisms of its biological activity remain obscure. Here, we analyzed the expression levels of the subunits of the CCR4-NOT complex in various mouse tissues and found that they showed distinct expression patterns. CNOT6, 6L, 7, and 10 were expressed nearly ubiquitously, whereas others were expressed in tissue-specific manners, such as those displaying especially high expression in the brain. Furthermore, CNOT2, 3, 6, and 8 were rapidly downregulated during differentiation of neural stem cells. These findings suggest that subunit composition of the CCR4-NOT complex differs among tissues and is altered during neural development, thereby imparting an additional layer of specificity in the control of gene expression.

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    • "The role of each subunit in the complex is also far from clear. The subunits of the CCR4-NOT complex show distinct tissue distributions (Chen et al., 2011), suggesting that the composition of the CCR4-NOT complex differs among tissues, which may reflect tissue-specific functions of this complex. Some subunits are thought to participate in transcriptional regulation. "
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