Jeziorski, Michael C.; Greenberg, Robert M.
Voltage-gated calcium (Ca2+) channels provide the pathway for Ca2+ influxes that
underlie Ca2+-dependent responses in muscles, nerves, and other excitable cells. They are also
targets of a wide variety of drugs and toxins. Ca2+ channels are multisubunit protein complexes
consisting of a pore-forming α1 subunit and other modulatory subunits, including the β subunit.
Here, we review the structure and function of schistosome Ca2+ channel subunits, with particular
emphasis on variant Ca2+ channel β subunits (Cavβvar) found in these parasites. In particular, we
examine the role these β subunits may play in the action of praziquantel, the current drug of
choice against schistosomiasis. We also present evidence that Cavβvar homologs are found in
other praziquantel-sensitive platyhelminths such as the pork tapeworm, Taenia solium, and that
these variant β subunits may thus represent a platyhelminth-specific gene family.