Truncations in the amino terminus reveal a region key to supporting amphetamine-induced efflux by the human serotonin transporter
نویسندگان
چکیده
Background The serotonin transporter (SERT) terminates neurotransmission via reuptake of serotonin from the synaptic cleft. Upon stimulation with amphetamines, SERT switches into an outward transport mode to rapidly release serotonin. We have previously shown that truncation of the first 64 residues of SERT amino terminus leads to loss of amphetamine-induced efflux [1]. This was comparable to the effects of a single point mutation of a juxtamembrane threonine residue at position 81 [1].
منابع مشابه
Mutations in the amino-terminus impair amphetamine-induced efflux by inducing inward-facing conformations of the serotonin transporter
Methods and results Our findings indicate that, although the mutated transporters are normally targeted to the plasma membrane, they exhibit marked functional defects, such as: (i) a dramatic decrease in amphetamine-induced efflux (despite retaining normal amphetamine-induced currents), (ii) a 3-fold reduction in transporter turnover numbers (indicating impaired substrate translocation) and (ii...
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عنوان ژورنال:
دوره 11 شماره
صفحات -
تاریخ انتشار 2011