Complex sentence: PDE6B, one of the catalytic units in rod PDE6, is composed of three domains: two N-terminal GAF domains and one C-terminal catalytic domain.The non-catalytic GAF domains are responsible for cGMP binding.
Split into simpler sentences: PDE6B, one of the catalytic units in rod PDE6, is composed of three domains. Two N-terminal GAF domains and one C-terminal catalytic domain.The non-catalytic GAF domains are responsible for cGMP binding.