Golgi apparatus localization of ZNT7 in the mouse cerebellum.

We have recently reported that four members of the zinc transporter (ZNT) family, ZNT1, ZNT3, ZNT4, and ZNT6, are abundantly expressed in the mouse cerebellum. In the present study, we reported that ZNT7 was present throughout the cerebellar cortex. ZNT7 immunoreactivity was predominately present in the somas and primary dendrites of the Purkinje cells. ZNT7 was also present in the Bergmann glial cell bodies as well as their radial processes, which extended into the molecular cell layer. Confocal immunofluorescence results demonstrated that the expression of ZNT7 overlapped with that of TGN38 in the somas of the Purkinje cells and granule cells. Immuno-electron microscopic study showed that ZNT7 was localized to the membrane of the Golgi apparatus in the somas of the Purkinje cells, Bergmann glial cells, and granule cells. Western blot analysis demonstrated that a considerable amount of ZNT7 was expressed in the cerebellum. These findings suggest a significant role of ZNT7 in zinc homeostasis in the mouse cerebellum.