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Published on: May 9, 2020
The nuclear experience of CPEB: implications for RNA processing and translational control
Chien-Ling Lin1, Veronica Evans, Shihao Shen
1University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
RNA (New York, N.Y.)
|December 31, 2009
Summary
Cytoplasmic polyadenylation element-binding protein (CPEB) shuttles between the nucleus and cytoplasm, regulating translation and alternative splicing. Nuclear CPEB and Maskin ensure mRNA translational repression after export.
Area of Science:
- Molecular Biology
- Cell Biology
- Developmental Biology
Background:
- CPEB is a key RNA-binding protein controlling translation via polyadenylation.
- It interacts with proteins like Gld2, PARN, and Maskin.
- CPEB's role in nuclear-cytoplasmic shuttling and its nuclear functions were unclear.
Purpose of the Study:
- To investigate the subcellular localization and nuclear functions of CPEB.
- To elucidate the mechanism of CPEB export from the nucleus.
- To understand CPEB's role in mRNA processing and translation regulation.
Main Methods:
- Xenopus oocyte nuclear export assays.
- Co-immunoprecipitation to identify interacting proteins.
- Analysis of mRNA processing and translation in mouse models.
Main Results:
- CPEB shuttles between the nucleus and cytoplasm via the CRM1-dependent pathway.
- In the nucleus, CPEB associates with chromosomes and RNA processing factors.
- CPEB interacts with Maskin and CPE-containing mRNAs in the nucleus, influencing cytoplasmic translational repression and mediating alternative splicing.
Conclusions:
- CPEB actively shuttles between cellular compartments, with nuclear export mediated by CRM1.
- Nuclear CPEB, alongside Maskin, plays a critical role in repressing mRNA translation post-export.
- Nuclear CPEB also participates in regulating pre-mRNA alternative splicing.
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