TY - JOUR

T1 - De novo mutation in the dopamine transporter gene associates dopamine dysfunction with autism spectrum disorder

AU - Hamilton, P J

AU - Campbell, N G

AU - Sharma, S

AU - Erreger, K

AU - Hansen, Freja Herborg

AU - Saunders, C

AU - Belovich, A N

AU - NIH ARRA Autism Sequencing Consortium

AU - Sahai, M A

AU - Cook, E H

AU - Gether, U

AU - McHaourab, H S

AU - Matthies, H J G

AU - Sutcliffe, J S

AU - Galli, A

PY - 2013/12

Y1 - 2013/12

N2 - De novo genetic variation is an important class of risk factors for autism spectrum disorder (ASD). Recently, whole-exome sequencing of ASD families has identified a novel de novo missense mutation in the human dopamine (DA) transporter (hDAT) gene, which results in a Thr to Met substitution at site 356 (hDAT T356M). The dopamine transporter (DAT) is a presynaptic membrane protein that regulates dopaminergic tone in the central nervous system by mediating the high-affinity reuptake of synaptically released DA, making it a crucial regulator of DA homeostasis. Here, we report the first functional, structural and behavioral characterization of an ASD-associated de novo mutation in the hDAT. We demonstrate that the hDAT T356M displays anomalous function, characterized as a persistent reverse transport of DA (substrate efflux). Importantly, in the bacterial homolog leucine transporter, substitution of A289 (the homologous site to T356) with a Met promotes an outward-facing conformation upon substrate binding. In the substrate-bound state, an outward-facing transporter conformation is required for substrate efflux. In Drosophila melanogaster, the expression of hDAT T356M in DA neurons-lacking Drosophila DAT leads to hyperlocomotion, a trait associated with DA dysfunction and ASD. Taken together, our findings demonstrate that alterations in DA homeostasis, mediated by aberrant DAT function, may confer risk for ASD and related neuropsychiatric conditions.

AB - De novo genetic variation is an important class of risk factors for autism spectrum disorder (ASD). Recently, whole-exome sequencing of ASD families has identified a novel de novo missense mutation in the human dopamine (DA) transporter (hDAT) gene, which results in a Thr to Met substitution at site 356 (hDAT T356M). The dopamine transporter (DAT) is a presynaptic membrane protein that regulates dopaminergic tone in the central nervous system by mediating the high-affinity reuptake of synaptically released DA, making it a crucial regulator of DA homeostasis. Here, we report the first functional, structural and behavioral characterization of an ASD-associated de novo mutation in the hDAT. We demonstrate that the hDAT T356M displays anomalous function, characterized as a persistent reverse transport of DA (substrate efflux). Importantly, in the bacterial homolog leucine transporter, substitution of A289 (the homologous site to T356) with a Met promotes an outward-facing conformation upon substrate binding. In the substrate-bound state, an outward-facing transporter conformation is required for substrate efflux. In Drosophila melanogaster, the expression of hDAT T356M in DA neurons-lacking Drosophila DAT leads to hyperlocomotion, a trait associated with DA dysfunction and ASD. Taken together, our findings demonstrate that alterations in DA homeostasis, mediated by aberrant DAT function, may confer risk for ASD and related neuropsychiatric conditions.

KW - Animals

KW - Child Development Disorders, Pervasive

KW - Child, Preschool

KW - Dopamine

KW - Dopamine Plasma Membrane Transport Proteins

KW - Dopaminergic Neurons

KW - Drosophila melanogaster

KW - Homeostasis

KW - Humans

KW - Male

KW - Motor Activity

KW - Mutation, Missense

KW - Risk Factors

U2 - 10.1038/mp.2013.102

DO - 10.1038/mp.2013.102

M3 - Journal article

C2 - 23979605

VL - 18

SP - 1315

EP - 1323

JO - Molecular Psychiatry

JF - Molecular Psychiatry

SN - 1359-4184

IS - 12

ER -