Synaptotagmin 4

A protein targeted to the Golgi compartment and LDCVs in NGF differentiated PC12 cells

General Information

Up to now at least 17 synaptotagmins have been identified. Synaptotagmin 4 is composed of a vesicular, a transmembrane and two C2 domains. Only the C2B domain is able to bind calcium. In the C2A domain one of the calcium binding aspartates has been substituted for serine leading to a loss of its binding capabilities.
The localization of synaptotagmin 4 is still under discussion. A localization to synaptic vesicles (SVs) has been postulated but more recent studies suggest that it is present in the Golgi compartment, in distal parts of neurites and on large dense core vesicles (LDCVs) of NGF differentiated PC12 cells.