Even if you don’t know what synaptic plasticity is, you should be thankful for it. Synaptic plasticity is the adjustment of a neuron’s response to a signal based on previous signal transmission, and many theorize that synaptic plasticity is the foundation for learning and memory. Today’s image is from a fascinating paper showing the role of myosin in organelle transport within a specific type of neuron, in a process that is important for synaptic plasticity.
Purkinje neurons are found in the cerebellar cortex of our brains, and play a large role in motor control. They are some of the largest neurons in our brain, so the transport of organelles within Purkinje neurons is no small feat. Dendritic spines are regions where the neuron receives its input signals, and the localization of ER (endoplasmic reticulum, a tubular organelle) in the spines is very important. After neuron stimulation, the ER releases calcium ions into the dendritic spine, which facilitates a type of synaptic plasticity in Purkinje neurons. A recent paper describes the role of myosin-Va, an actin motor, in transporting and localizing the ER to dendritic spines in these neurons. Images above are of a mouse Purkinje neuron (top), and a higher magnification view of a region of a Purkinje neuron (bottom). The white dot in the bottom panel is where a form of glutamate was uncaged at the tip of a dendritic spine in order to stimulate that specific spine on the neuron, and the yellow line indicates the line scan of the microscope.
Wagner, W., Brenowitz, S., & Hammer, J. (2010). Myosin-Va transports the endoplasmic reticulum into the dendritic spines of Purkinje neurons Nature Cell Biology, 13 (1), 40-48 DOI: 10.1038/ncb2132