DN gene family

Genes in the DN gene family provide instructions for making proteins that group together to form a complex called dynein. Dynein is found within cell structures called cilia, which 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. Dynein produces the force needed for cilia to move.

Dynein is found within the core of cilia (the axoneme). The axoneme is supported by rigid, hollow fibers called microtubules, which are linked together to form a circle. The dynein molecules are part of structures called inner dynein arms (IDAs) that are attached to the inside of this circle and structures called outer dynein arms (ODA) that are attached to the outside of this circle. Coordinated movement of the dynein arms causes the microtubules to slide against each other, which makes the entire axoneme bend. The protein components (subunits) that make up the dynein arms are classified by their weight as heavy, intermediate, or light chains. Each subunit is produced from a different gene, and ODAs have a different combination of subunits than IDAs.

Researchers have identified at least 18 genes in the DN gene family. Mutations in several of these genes have been found to cause primary ciliary dyskinesia, a disorder caused by impaired movement of cilia.