serotonin receptor subtypes B1 and B2 from Aplysia californica and similar proteins; member of the class A family of seven-transmembrane G protein-coupled receptors
This subfamily includes Aplysia californica serotonin receptors Ap5-HTB1 and Ap5-HTB2, and similar proteins from bilateria including insects, mollusks, annelids, and worms. Ap5-HTB1 is one of the several different receptors for 5-hydroxytryptamine (5HT, serotonin). In Aplysia, serotonin plays important roles in a variety of behavioral and physiological processes mediated by the central nervous system. These include circadian clock, feeding, locomotor movement, cognition and memory, synaptic growth and synaptic plasticity. Both Ap5-HTB1 and Ap5-HTB2 receptors are coupled to G-proteins that stimulate phospholipase C, leading to the activation of phosphoinositide metabolism. Ap5-HTB1 is expressed in the reproductive system, whereas Ap5-HTB2 is expressed in the central nervous system.
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