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Updated: Jun 30, 2026
09:42
Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides
Published on: June 19, 2012
Sequence-encoded autoinhibition couples mRNA decapping activity to phase separation
Trase Aguigam1,2, Katarzyna Grab3,4, Joanna Kowalska3
1Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA.
Biorxiv : the Preprint Server for Biology
|June 29, 2026
Summary
Fission yeast Dcp2
Area of Science:
- Molecular Biology
- Biochemistry
- RNA Biology
Background:
- Messenger RNA (mRNA) decapping by the Dcp1/Dcp2 complex initiates degradation.
- Regulatory mechanisms controlling Dcp1/Dcp2 complex activity are not fully understood.
- The 5' cap structure is crucial for mRNA stability and translation initiation.
Purpose of the Study:
- To investigate the regulatory mechanisms of the Dcp1/Dcp2 decapping complex.
- To identify specific protein regions and interactions that control Dcp2 activity.
- To understand how Dcp2 functions within phase-separated biomolecular condensates.
Main Methods:
- Site-directed mutagenesis of fission yeast Dcp2.
- Biochemical assays measuring decapping activity and RNA binding.
- Analysis of protein behavior within phase-separated condensates.
Main Results:
- Identified inhibitory motifs in the Dcp2 C-terminus that repress catalytic activity.
- Mutations relieving autoinhibition enhanced RNA binding and bypassed the need for the activator Edc3.
- Dcp2 activation within phase-separated condensates is maintained, showing propagation of conformational changes.
- Long-range interactions between the Dcp2 intrinsically disordered region and its catalytic core restrict RNA binding.
Conclusions:
- Sequence-encoded elements in the Dcp2 C-terminus allosterically regulate its catalytic activity.
- Intrinsically disordered regions play a key role in modulating enzyme function within biomolecular condensates.
- Understanding these regulatory mechanisms provides insights into mRNA decay pathways and protein function in condensates.
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