regulation of centriole-centriole cohesion

Definition

Target type: biologicalprocess

Any process that modulates the extent to which the two centrioles within a centrosome remain tightly paired; may be mediated by the assembly and disassembly of a proteinaceous linker. [PMID:11076968]

Centriole-centriole cohesion, a critical process for proper centrosome duplication and function, is tightly regulated by a complex interplay of protein interactions and post-translational modifications. This intricate mechanism ensures the faithful duplication of centrioles, the essential microtubule-organizing centers in eukaryotic cells.

During the S phase of the cell cycle, a mature centriole acts as a template for the formation of a new, daughter centriole. This process, known as centriole biogenesis, involves the assembly of a proteinaceous cartwheel structure around the proximal end of the mother centriole, followed by the sequential addition of microtubule triplets, forming the daughter centriole.

As the daughter centriole elongates, it remains tethered to the mother centriole, forming a cohesive pair. This cohesion is essential for the proper positioning and function of the centrosome during cell division. Centriole-centriole cohesion is maintained throughout the cell cycle until the next round of centriole duplication.

Several key proteins have been identified as crucial regulators of centriole-centriole cohesion. Among these are:

* **SAS-6:** This protein is a scaffold protein that plays a pivotal role in the assembly of the cartwheel structure at the base of the daughter centriole. It directly interacts with other centriolar proteins, including SAS-4, contributing to the initial formation of the daughter centriole and its attachment to the mother centriole.
* **CEP135:** This protein is essential for the recruitment of SAS-6 to the mother centriole, ensuring proper initiation of daughter centriole formation.
* **CEP170:** This protein is a large, coiled-coil protein that acts as a linker between the mother and daughter centrioles. It interacts with both SAS-6 and the microtubule triplets of the daughter centriole, maintaining cohesion throughout the centriole elongation process.
* **CPAP:** This protein is involved in the regulation of centriole length and plays a role in linking the two centrioles together. It acts as a microtubule-stabilizing protein, ensuring the proper assembly and integrity of the centriole microtubule structure.

The cohesion between the two centrioles is not static, but rather is dynamically regulated throughout the cell cycle. This regulation involves post-translational modifications, such as phosphorylation and ubiquitination, which can alter the interactions between proteins and affect the stability of the cohesion complex.

For example, phosphorylation of CEP135 by Polo-like kinase 1 (PLK1) during mitosis promotes the separation of the centrioles, allowing them to migrate to opposite poles of the cell and initiate spindle formation. This separation is essential for accurate chromosome segregation during cell division.

In summary, the regulation of centriole-centriole cohesion is a complex and multifaceted process involving a tightly orchestrated interplay of protein interactions and post-translational modifications. This dynamic regulation ensures the faithful duplication of centrioles, allowing for the proper function of the centrosome in cell division and other cellular processes.'"

Proteins (1)

Compounds (6)