Calmodulin, a calmodulin acceptor protein, and calcimedins: unique antibody localizations in hamster sperm

A calmodulin acceptor protein has been identified in isolated hamster caudal sperm by immunofluorescence and Western transfer techniques. The protein shows a localization in sperm heads identical to calmodulin. Fluorescence of both calmodulin and the acceptor protein are lost by treatment with MgCl2, conditions which release the acrosome. These results are consistent with the proposed function of calmodulin in a sperm function.