Imaging of spine synapses using super-resolution microscopy

Neuronal circuits in the neocortex and hippocampus are essential for higher brain functions such as motor learning and spatial memory. In the mammalian forebrain, most excitatory synapses of pyramidal neurons are formed on spines, which are tiny protrusions extending from the dendritic shaft. The spine contains specialized molecular machinery that regulates synaptic transmission and plasticity. Spine size correlates with the efficacy of synaptic transmission, and spine morphology affects signal transduction at the post-synaptic compartment. Plasticity-related changes in the structural and molecular organization of spine synapses are thought to underlie the cellular basis of learning and memory. Recent advances in super-resolution microscopy have revealed the molecular mechanisms of the nanoscale synaptic structures regulating synaptic transmission and plasticity in living neurons, which are difficult to investigate using electron microscopy alone. In this review, we summarize recent advances in super-resolution imaging of spine synapses and discuss the implications of nanoscale structures in the regulation of synaptic function, learning, and memory.

Automated summary

Neuronal circuits in the neocortex and hippocampus play a crucial role in higher brain functions and are regulated by spine synapses. Advances in super-resolution microscopy have revealed the molecular mechanisms of nanoscale synaptic structures in living neurons, which have significant implications for synaptic function, learning, and memory. Spine size and morphology are closely related to synaptic transmission efficacy and signal transduction, contributing to the cellular basis of cognition.