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Updated: May 31, 2026
06:27
Isolation and Characterization of Exosomes from Skeletal Muscle Fibroblasts
Published on: May 16, 2020
Functions of the cytoplasmic exosome
Daneen Schaeffer1, Amanda Clark, A Alejandra Klauer
1Department of Microbiology and Molecular Genetics, University of Texas Health Science Center-Houston, Houston, Texas, USA.
Advances in Experimental Medicine and Biology
|June 30, 2011
Summary
The cytoplasmic exosome, a protein complex, degrades cellular messenger RNAs (mRNAs). Specific cofactors guide this essential complex to its targets, but their exact functions remain under investigation.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- The exosome is a multi-protein complex essential for RNA processing and degradation.
- It functions in both the nucleus and cytoplasm of eukaryotic cells.
- The cytoplasmic exosome plays a role in mRNA turnover and surveillance.
Purpose of the Study:
- To review the known cofactors and functions of the cytoplasmic exosome.
- To highlight unanswered questions regarding the mechanisms of cytoplasmic exosome action.
Main Methods:
- Literature review of existing studies on the cytoplasmic exosome.
- Analysis of conserved functional aspects between yeast and metazoan exosomes.
Main Results:
- The exosome core comprises ten essential proteins, including ribonuclease Rrp44p.
- Four specific cofactors are involved in cytoplasmic exosome functions, distinct from nuclear roles.
- These cofactors are presumed to direct the exosome to cytoplasmic RNA substrates.
Conclusions:
- The cytoplasmic exosome is crucial for mRNA metabolism and surveillance.
- Further research is needed to elucidate the precise mechanisms by which cofactors mediate cytoplasmic exosome function.
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