The polypeptide chains of lipoprotein complexes are referred to as apoproteins. For example, HDLs, VLDLs, IDLs, LDLs, and chylomicrons are all lipoprotein complexes, but the polypeptide chains within them, such as Apo A-I, Apo B-100, or Apo E, are all apoproteins.

The apoproteins of the lipoprotein complexes are shown below:

Apo A-I	Apo A-II	Apo B-100
Apo B-48	Apo C-I	Apo C-II
Apo C-III	Apo D	Apo E