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Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes
Published on: September 13, 2022
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ULK1 phosphorylates Mad1 to regulate spindle assembly checkpoint.
Fengjie Yuan1, Ximin Jin1, Dan Li2,3,4,5
1Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
Nucleic Acids Research
|July 11, 2019
Summary
The serine/threonine kinase ULK1 activates the spindle assembly checkpoint (SAC) by phosphorylating Mad1, ensuring accurate chromosome segregation. ULK1 deletion impairs cancer cell growth and increases sensitivity to paclitaxel.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The spindle assembly checkpoint (SAC) is crucial for accurate chromosome segregation during cell division.
- ULK1 is a known kinase involved in initiating autophagy.
Purpose of the Study:
- To investigate the role of ULK1 in the spindle assembly checkpoint (SAC).
- To elucidate the mechanism by which ULK1 regulates SAC activity.
Main Methods:
- * Phosphorylation site analysis of Mad1.
- * Kinetochore recruitment assays.
- * Analysis of chromosome instability and cell viability in ULK1-deleted cells.
- * Paclitaxel cytotoxicity assays.
Main Results:
- * ULK1 phosphorylates Mad1 at Ser546, facilitating its kinetochore recruitment.
- * The Rod/ZW10/Zwilch (RZZ) complex interacts with phosphorylated Mad1.
- * ULK1 deficiency leads to increased chromosome instability.
- * Deletion of ULK1 enhances paclitaxel-induced cytotoxicity and impairs cancer cell growth.
Conclusions:
- * ULK1 is a novel regulator of the spindle assembly checkpoint.
- * ULK1-mediated phosphorylation of Mad1 is essential for SAC function.
- * ULK1 plays a significant role in maintaining genomic stability and influencing cancer cell response to chemotherapy.
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