The ribbon synapse is a type of neuronal synapse which is characterized by unique mechanisms of multivesicular release and calcium channel positioning which promote rapid neurotransmitter release and signal transmission. Ribbon synapses undergo an ongoing cycle of exocytosis and endocytosis in response to graded changes of membrane potential.
These unique features specialize the ribbon synapse to enable extremely fast, precise and sustained neurotransmissions, which are critical for the perception of complex senses such as vision and hearing. Ribbon synapses are found in retinal photoreceptor cells, vestibular organ receptors, cochlear hair cells and retinal bipolar cells.
The synaptic ribbon is a unique structure at the synapse's active zone. It hovers several nanometers above the pre-synaptic membrane and tethers 100 or more synaptic vesicles. Each pre-synaptic cell can have from 10 to 100 ribbons tethered to it raising the total count to 1000-10000 vesicles.
Read more about Ribbon Synapse: Function
Famous quotes containing the word ribbon:
“I’ll tell you how the Sun rose—
A Ribbon at a time—”
—Emily Dickinson (1830–1886)