Basal body

Eukarya Flagella

Chlamydomonas TEM 09

Basal body is a cellular structure that is critical in the formation of cilia and flagella in eukaryotic cells. It serves as a template for the growth of the axoneme, the core part of a cilium or flagellum, and is essential for their proper function. Basal bodies are derived from centrioles, and they share a similar structure, but their functions diverge significantly.

Structure

The basal body has a cylindrical shape, consisting of nine triplet microtubule blades arranged in a circular pattern around the perimeter, without the central microtubule pair found in cilia and flagella. This 9+0 structure is characteristic of centrioles, from which basal bodies originate. The basal body acts as a microtubule-organizing center (MTOC), anchoring and organizing the microtubules that extend into the cilium or flagellum.

Function

The primary function of the basal body is to initiate the growth of cilia and flagella and to anchor these structures to the cell. Cilia and flagella are important for a variety of cellular processes, including motility, sensory functions, and signaling. The basal body ensures the proper orientation and positioning of these appendages, facilitating their correct assembly and function.

In addition to its structural role, the basal body is involved in the signaling pathways that regulate cell cycle and cell division. It plays a critical role in ensuring that cilia and flagella are correctly formed and functional, which is essential for the health and viability of the cell.

Clinical Significance

Mutations affecting basal body structure or function can lead to a range of human diseases, collectively known as ciliopathies. These include conditions such as primary ciliary dyskinesia, Bardet-Biedl syndrome, and polycystic kidney disease. These diseases can affect multiple organ systems, reflecting the widespread importance of cilia and flagella in human physiology.

See Also

• Centriole
• Cilium
• Flagellum
• Microtubule
• Ciliopathy