The main components of the nuclear pore complex include: 

Columnar subunits– Columnar subunits are integral proteins that make up the major portion of the nuclear pore complex. They traverse the nuclear membrane. 

Ring subunits– Appearing as circular structures, ring subunits make up the outer and inner boundaries of the nuclear pore complex against the membrane. 

Annular subunits– Annular subunits occur in a radial arrangement in the nuclear pore complex. 

Luminal subunits– Luminal subunits occur between the 2 layers of the double membrane. They help to keep the nuclear pore complex anchored to the nuclear membrane. 

Fibrils– Fibrils extend into the cytoplasm as filaments.