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coiled-coil domain 40 molecular ruler complex subunit

The CCDC40 gene provides instructions for making a protein that is involved in the assembly of a larger group of proteins (a complex) called dynein. Dynein functions within cell structures called cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. Coordinated back and forth movement of cilia can move the cell or the fluid surrounding the cell. Flagella are similar to cilia, but flagella are found only in sperm cells. Dynein makes up the structures (arms) that produce the force needed for cilia and flagella to move. 

Normal function

The CCDC40 gene provides instructions for making a protein that is involved in the assembly of a larger group of proteins (a complex) called dynein. Dynein functions within cell structures called cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. Coordinated back and forth movement of cilia can move the cell or the fluid surrounding the cell. Flagella are similar to cilia, but flagella are found only in sperm cells. Dynein makes up the structures (arms) that produce the force needed for cilia and flagella to move. 

Dynein forms structures known as inner dynein arms (IDAs) and outer dynein arms (ODAs) within the core of cilia and flagella (the axoneme). Coordinated movement of the dynein arms causes the entire axoneme to bend back and forth. The CCDC40 protein is necessary for the proper assembly of the IDAs, which play a central role in the coordinated movement of cilia and flagella. 

Researchers suspect that the CCDC40 protein is also involved in the proper assembly of the nexin-dynein regulatory complex, which helps regulate and coordinate the activity of the inner and outer dynein arms. By helping with the assembly of both the IDAs and the nexin-dynein regulatory complex, the CCDC40 protein plays a central role in the coordinated movement of cilia and flagella. 

Conditions referring to this gene or chromosome

Other names

CFAP172

coiled-coil domain containing 40

coiled-coil domain containing protein 40

FAP172

FLJ20753

FLJ32021

KIAA1640

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Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.
  • 30 Sept 2025 | Latest version
  • 1 Sept 2025 | Originally published

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