The dimeric unit is held together by a four-helix bundle, formed when the C-terminal segments of the α1 helices on each subunit interact in an antiparallel manner with both α2 helices.
A unidade dímera mantense unida por un conxunto de catro hélices, formado cando os segmentos C-terminais da hélice α1 de cada subunidade interacciona de maneira antiparalela con ambas as hélices α2.