Pre-synaptic and Post-synaptic Markers

Synapses are the site for brain communication where information is transmitted between neurons and stored for memory formation. Synaptic degeneration is a global and early pathogenic event in neurodegenerative disorders with reduced levels of pre- and postsynaptic proteins being recognized as a core feature of Alzheimer’s disease (AD) pathophysiology. Together with AD, other neurodegenerative and neurodevelopmental disorders show altered synaptic homeostasis as an important pathogenic event, and due to that, they are commonly referred to as synaptopathies. 

 Pre-synaptic Markers: Pre-synaptic markers are primarily associated with synaptic vesicles, the active zone, and neurotransmitter release machinery. 

 Post-synaptic Markers: Post-synaptic markers concentrate in the PSD, a protein-dense region beneath the post-synaptic membrane that anchors receptors and signaling complexes. 

 Co-localization of pre- and post-synaptic markers (e.g., SYP + PSD-95) is the gold standard for identifying functional synapses in imaging studies. These markers are indispensable for studying synaptic development, plasticity, and pathology in neurodegenerative and neuropsychiatric disorders.