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Updated: May 22, 2026
12:02
Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
Published on: June 6, 2017
Structural basis for homeodomain recognition by the cell-cycle regulator Geminin
Bo Zhou1, Changdong Liu, Zhiwen Xu
1Division of Life Science and State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Kowloon, Hong Kong.
Summary
Geminin protein binds to Hox homeodomains, inhibiting their function and controlling cell proliferation. This interaction is specific and can be further regulated by Geminin phosphorylation, offering new insights into transcription factor regulation.
Area of Science:
- Molecular Biology
- Structural Biology
- Developmental Biology
Background:
- Homeodomain transcription factors regulate key cellular and developmental processes.
- Protein partners modulate homeodomain function, but the mechanisms are poorly understood.
Purpose of the Study:
- To elucidate the structural basis of Hox homeodomain interaction with Geminin.
- To understand how Geminin regulates Hox transcriptional activity and cell proliferation.
Main Methods:
- Solution structure determination of the Hox homeodomain-Geminin complex.
- Analysis of protein-protein interactions and functional assays.
Main Results:
- The structure reveals specific electrostatic and van der Waals interactions between Geminin and the Hox homeodomain.
- Geminin binding is selective for homeodomain subclasses and Hox paralogs.
- Geminin phosphorylation by Casein kinase II enhances binding to Hox and inhibits its activity.
Conclusions:
- Geminin acts as a cell-cycle regulator by inhibiting Hox transcriptional activity through a specific structural interaction.
- The findings provide a molecular mechanism for homeodomain-protein recognition and inhibition.
- This interaction serves as a model for peptide inhibitors targeting homeodomains.
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