Acetylcholine Transporter

Updated: 2026-08-07

Overview

The acetylcholine transporter (AChT) is a vesicular membrane protein encoded by the SLC18A3 gene, primarily expressed in cholinergic neurons. It transports acetylcholine into synaptic vesicles using a proton gradient, enabling neurotransmitter storage and subsequent release during synaptic transmission. Discovered in the 1990s, AChT is structurally related to other monoamine transporters but shows distinct pharmacological properties. As a key regulator of cholinergic signaling, AChT dysfunction has been implicated in neurological disorders such as Alzheimer's disease and myasthenia gravis. Research-grade AChT is commonly purified from recombinant expression systems for biochemical assays and drug screening applications.

Physical and Chemical Properties

AChT is a 12-transmembrane domain protein with molecular weight varying between 50-70 kDa across species due to glycosylation differences. The protein operates as an antiporter, exchanging two luminal protons for one cytoplasmic acetylcholine molecule. Its activity is optimal at pH 7.0-7.4 and is strongly inhibited by vesamicol derivatives. In research settings, AChT is typically supplied as a lyophilized powder or glycerol solution. The protein exhibits stability for 6-12 months at -80°C when properly aliquoted, but loses activity after repeated freeze-thaw cycles. Reconstitution requires mild detergents like CHAPS or n-dodecyl-β-D-maltoside to maintain functionality.

Main Applications

In neuroscience research, AChT is primarily used to study presynaptic cholinergic mechanisms and screen potential cognitive enhancers. Radiolabeled AChT ligands ([3H]vesamicol) enable quantitative binding assays for investigating neurotransmitter transport kinetics. Pharmaceutical companies utilize recombinant AChT in high-throughput screening platforms for Alzheimer's drug candidates. Additional applications include the development of diagnostic tools for myasthenic syndromes and research into autonomic nervous system disorders. Recent studies also explore AChT's role in neuroinflammation and its potential as a biomarker for early neurodegenerative disease detection.

Safety and Storage

Research-grade AChT preparations are classified as Biosafety Level 1 materials, requiring standard laboratory precautions including gloves and eye protection. Avoid inhalation of lyophilized powder during reconstitution. Spills should be cleaned with 70% ethanol followed by detergent washing. For long-term storage, aliquot protein solutions in small volumes using cryoprotectants (e.g., 10% glycerol) and store at -80°C. Working solutions can be kept at 4°C for up to 1 week with protease inhibitors. Always verify protein concentration via Bradford assay before experimental use to ensure consistency across studies.

B2B Procurement Guide

When sourcing AChT for research purposes, prioritize suppliers with ISO 13485 certification for protein production. Key specifications to request include: Western blot verification of purity (>95%), transport activity data (typically 0.5-2 nmol/min/mg), and endotoxin levels (<1 EU/μg). Consider species compatibility - human AChT differs from rodent isoforms by 5-8% in amino acid sequence. Bulk purchasers (>10 mg) should negotiate batch-to-batch consistency guarantees and request stability data. Leading suppliers include Merck Millipore, Abcam, and Sino Biological, with lead times of 4-6 weeks for custom expressions. For screening applications, pre-coated microplates with immobilized AChT are available at approximately $500/plate.