Restoration of Physiological Expression of 5-HT Receptor into the Primary Cilia of Null Mutant Neurons Lengthens Both Primary Cilia and Dendrites.

5-HT (serotonin) receptors are promising targets for a variety of neuropsychiatric disorders and have been linked to several cellular signaling cascades. Endogenous 5-HT receptors are restricted to the primary neuronal cilium, a small sensory organelle stemming from the cell body that receives numerous extrasynaptic signals. Inhibition of 5-HT receptors decreases cilia length in primary neuronal cultures, but the signaling mechanisms involved are still unclear.