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Updated: May 8, 2026
10:44
Chemical Inactivation of the E3 Ubiquitin Ligase Cereblon by Pomalidomide-based Homo-PROTACs
Published on: May 15, 2019
EMI1, a three-in-one ubiquitylation inhibitor
Nature Structural & Molecular Biology
|August 29, 2013
Summary
Early mitotic inhibitor 1 (EMI1) naturally inhibits the anaphase-promoting complex/cyclosome (APC/C). New research reveals EMI1’s complex mechanisms controlling APC/C ubiquitylation during cell division.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The anaphase-promoting complex/cyclosome (APC/C) is a crucial E3 ubiquitin ligase essential for cell cycle progression.
- Early mitotic inhibitor 1 (EMI1) is a key regulator that inhibits APC/C activity during mitosis.
- Understanding EMI1's inhibitory mechanisms is vital for comprehending cell cycle control.
Discussion:
- This study investigates the multimodal inhibitory mechanisms employed by EMI1 against the APC/C.
- Findings highlight how EMI1 precisely controls APC/C-dependent ubiquitylation through distinct molecular interactions.
- The research elucidates the intricate regulation of APC/C activity by its natural inhibitor, EMI1.
Key Insights:
- EMI1 utilizes multiple strategies to inhibit the APC/C, ensuring proper cell cycle progression.
- These inhibitory mechanisms directly impact APC/C-dependent ubiquitylation, a critical process for protein degradation.
- The findings provide a deeper understanding of how APC/C function is regulated at the molecular level.
Outlook:
- Further research could explore the therapeutic potential of targeting EMI1-APC/C interactions in diseases like cancer.
- Investigating the structural basis of EMI1-APC/C binding may reveal new avenues for drug development.
- Comparative studies across different metazoan species could uncover conserved and divergent regulatory roles of EMI1.
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