Conserved molecular interactions in centriole-to-centrosome conversion

Area of Science:

• Cell Biology
• Molecular Biology
• Genetics

Background:

• Centrioles are crucial for forming centrosomes, which organize cell division, and cilia, involved in motility and signaling.
• Newly formed centrioles mature during the cell cycle, transitioning into centrosomes during mitosis to support duplication and pericentriolar material organization.

Purpose of the Study:

• To elucidate the molecular mechanisms underlying centriole-to-centrosome conversion during mitosis.
• To identify the key proteins and their sequential loading required for this critical cellular process.

Main Methods:

• Investigated protein localization and interactions during mitotic progression in Drosophila melanogaster and human cells.
• Utilized genetic and molecular approaches to analyze the function of specific proteins like Cep135, Ana1, and Asterless.

Main Results:

• Demonstrated that centriole-to-centrosome conversion depends on the sequential recruitment of Cep135, Ana1 (Cep295), and Asterless (Cep152) to daughter centrioles.
• Revealed that Ana1 acts as a molecular strut, and its function can be replaced by engineered fragments, highlighting a conserved structural framework.
• Showcased the essential role of this framework in recruiting Asterless/Cep152, a partner of Plk4, the master regulator of centriole duplication.

Conclusions:

• Uncovered the molecular basis of centriole-to-centrosome conversion, establishing a conserved protein network essential for centrosome maturation.
• This conversion process equips daughter centrioles with the necessary components to function as mother centrioles in the subsequent cell cycle.