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Molecular and Cellular Neuroscience Commons

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Selected Works

Haley Melikian

Articles 1 - 2 of 2

Full-Text Articles in Molecular and Cellular Neuroscience

Dopamine Transporter Endocytic Trafficking In Striatal Dopaminergic Neurons: Differential Dependence On Dynamin And The Actin Cytoskeleton., Haley Melikian Dec 2012

Dopamine Transporter Endocytic Trafficking In Striatal Dopaminergic Neurons: Differential Dependence On Dynamin And The Actin Cytoskeleton., Haley Melikian

Haley Melikian

Dopaminergic signaling profoundly impacts rewarding behaviors, movement, and executive function. The presynaptic dopamine (DA) transporter (DAT) recaptures released DA, thereby limiting synaptic DA availability and maintaining dopaminergic tone. DAT constitutively internalizes and PKC activation rapidly accelerates DAT endocytosis, resulting in DAT surface loss. Longstanding evidence supports PKC-stimulated DAT trafficking in heterologous expression studies. However, PKC-stimulated DAT internalization is not readily observed in cultured dopaminergic neurons. Moreover, conflicting reports implicate both classic and nonclassic endocytic mechanisms mediating DAT trafficking. Prior DAT trafficking studies relied primarily upon chronic gene disruption and dominant-negative protein expression, or were performed in cell lines and cultured …


Nonclassical, Distinct Endocytic Signals Dictate Constitutive And Pkc-Regulated Neurotransmitter Transporter Internalization, Haley Melikian Dec 2004

Nonclassical, Distinct Endocytic Signals Dictate Constitutive And Pkc-Regulated Neurotransmitter Transporter Internalization, Haley Melikian

Haley Melikian

Neurotransmitter transporters are critical for synaptic neurotransmitter inactivation. Transporter inhibitors markedly increase the duration and magnitude of synaptic transmission, underscoring the importance of transporter activity in neurotransmission. Recent studies indicate that membrane trafficking dynamically governs neuronal transporter cell-surface presentation in a protein kinase C-regulated manner, suggesting that transporter trafficking profoundly affects synaptic signaling. However, the molecular architecture coupling neurotransmitter transporters to the endocytic machinery is not defined. Here, we identify nonclassical, distinct endocytic signals in the dopamine transporter (DAT) that are necessary and sufficient to drive constitutive and protein kinase C-regulated DAT internalization. The DAT internalization signal is conserved across …