Functional Rescue of a Misfolded Drosophila melanogaster Dopamine Transporter Mutant Associated with a Sleepless Phenotype by Pharmacological Chaperones.
Ameya Kasture, Ali El-Kasaby, Daniel Szöllősi, H M Mazhar Asjad, Alexandra Grimm, Thomas Stockner, Thomas Hummel, Michael Freissmuth, Sonja Sucic
Journal of Biological Chemistry August 1, 2016 DOI: 10.1074/jbc.m116.737551 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Preclinical experimental study Peer reviewed |
|---|---|
| Population | Drosophila melanogaster dDAT-G108Q mutant flies and heterologously expressed dDAT-G108Q and hDAT-G140Q in cells |
| Interventions | Noribogaine Pifithrin-μ |
| Topics | Ibogaine |
| Keywords | Animals Humans Drosophila melanogaster Sulfonamides Drosophila proteins Sleep Protein folding Phenotype Mutation Molecular dynamics simulation Chaperone Drug action Dopamine transporter Endoplasmic reticulum er |
| Key findings | The folding-defective dopamine transporter mutants dDAT-G108Q and hDAT-G140Q are retained in the endoplasmic reticulum in complex with calnexin and HSP70-1A. Noribogaine and/or pifithrin-μ restored folding, dopamine transport, axonal delivery, and sleep time (from 300 to 1000 min/day) in dDAT-G108Q flies. The authors argue that pharmacochaperoning may offer a therapeutic approach for disorders caused by folding-defective DAT and related SLC6 transporters. |
Abstract
Folding-defective mutants of the human dopamine transporter (DAT) cause a syndrome of infantile dystonia/parkinsonism. Here, we provide a proof-of-principle that the folding deficit is amenable to correction in vivo by two means, the cognate DAT ligand noribogaine and the HSP70 inhibitor, pifithrin-μ. We examined the Drosophila melanogaster (d) mutant dDAT-G108Q, which leads to a sleepless phenotype in flies harboring this mutation. Molecular dynamics simulations suggested an unstable structure of dDAT-G108Q consistent with a folding defect. This conjecture was verified; heterologously expressed dDAT-G108Q and the human (h) equivalent hDAT-G140Q were retained in the endoplasmic reticulum in a complex with endogenous folding sensors (calnexin and HSP70-1A). Incubation of the cells with noribogaine (a DAT ligand selective for the inward-facing state) and/or pifithrin-μ (an HSP70 inhibitor) restored folding of, and hence dopamine transport by, dDAT-G108Q and hDAT-G140Q. The mutated versions of DAT were confined to the cell bodies of the dopaminergic neurons in the fly brain and failed to reach the axonal compartments. Axonal delivery was restored, and sleep time was increased to normal length (from 300 to 1000 min/day) if the dDAT-G108Q-expressing flies were treated with noribogaine and/or pifithrin-μ. Rescuing misfolded versions of DAT by pharmacochaperoning is of therapeutic interest; it may provide opportunities to remedy disorders arising from folding-defective mutants of human DAT and of other related SLC6 transporters.
Comparable studies
Other preclinical and animal studies on ibogaine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Noncompetitive Functional Inhibition at Diverse, Human Nicotinic Acetylcholine Receptor Subtypes by Bupropion, Phencyclidine, and Ibogaine TE671/RD cells (human muscle-type nAChR) and SH-SY5Y neuroblastoma cells (human... | 1999 | In vitro study | |
| Degeneration of Purkinje cells in parasagittal zones of the cerebellar vermis after treatment with ibogaine or harmaline. Ibogaine- or harmaline-treated rats | 1993 | Experimental animal study | |
| Effects and aftereffects of ibogaine on morphine self-administration in rats. Rats | 1991 | Preclinical experimental study | |
| Effects of iboga alkaloids on morphine and cocaine self-administration in rats: relationship to tremorigenic effects and to effects on dopamine release in nucleus accumbens and striatum. Rats | 1994 | Experimental study | |
| Glial Cell Line-Derived Neurotrophic Factor Mediates the Desirable Actions of the Anti-Addiction Drug Ibogaine against Alcohol Consumption Rats | 2005 | Experimental study |
Citations in the library
Cited by 6
- SLC6 Transporter Folding Diseases and Pharmacochaperoning. Handbook of experimental pharmacology 2018
- Tropane-Based Ibogaine Analog Rescues Folding-Deficient Serotonin and Dopamine Transporters. ACS Pharmacology & Translational Science April 9, 2021
- Main targets of ibogaine and noribogaine associated with its putative anti-addictive effects: A mechanistic overview. Journal of Psychopharmacology December 1, 2023
- Bedside to bench: the outlook for psychedelic research Frontiers in Pharmacology October 2, 2023
- Structure-Activity Relationships of Dopamine Transporter Pharmacological Chaperones. Frontiers in Cellular Neuroscience 2022
and 1 more in the library
Cites 2
- Ibogaine, a noncompetitive inhibitor of serotonin transport, acts by stabilizing the cytoplasm-facing state of the transporter. Journal of Biological Chemistry October 5, 2007
- The mechanistic basis for noncompetitive ibogaine inhibition of serotonin and dopamine transporters. Journal of Biological Chemistry May 25, 2012