Figure 11.

OMP, OR6B2, Golf, and AC3 are localized in compartment-specific locations in human and rat spermatozoa. In rat spermatozoa, OMP, Golf, and AC3 are simultaneously expressed on the head (acrosomal region and equatorial segment), the connecting piece, and along the tail, with strongest expression on the middle piece. In control human spermatozoa, OMP co-expresses with OR6B2 on the head (equatorial segment), and along the tail, except for the middle piece. In the hyperactivated spermatozoa, OMP co-expresses with OR6B2 on the head (acrosome), and along the tail, except for the middle piece. In control and hyperactivated spermatozoa, OMP is singly expressed on the connecting piece. A clear difference in the pattern of OMP expression between human (both control and hyperactivated) and rat spermatozoa is observed on the middle piece. The differences in the pattern of OMP and OR6B2 co-expression between the control and hyperactivated human spermatozoa are observed on the head, with no changes of OMP single expression on the connecting piece. Abbreviations: OMP, olfactory marker protein; OR, olfactory receptor (OR6B2); AC3, adenylyl cyclase 3; Golf, olfactory G protein.