Choline acetyltransferase

Choline acetyltransferase (ChAT) is an enzyme that is involved in the synthesis of the neurotransmitter acetylcholine. ChAT catalyzes the transfer of an acetyl group from the coenzyme acetyl-CoA to choline, yielding acetylcholine. This enzyme is found in high concentrations in cholinergic neurons, both in the central nervous system (CNS) and in peripheral neurons.

Function

Choline acetyltransferase is a critical enzyme in the production of acetylcholine, a neurotransmitter that plays a key role in many functions of the nervous system. Acetylcholine is involved in functions such as muscle contraction, pain response, learning, and memory. The activity of ChAT is often used as a marker for the health and integrity of cholinergic neurons.

Structure

Choline acetyltransferase is a soluble enzyme and is structurally classified as a member of the CoA-transferase family of enzymes. It is composed of multiple domains, including a catalytic domain, a choline binding domain, and a domain that binds acetyl-CoA.

Clinical significance

Alterations in the activity of ChAT are associated with a number of neurological disorders. For example, decreased ChAT activity is seen in Alzheimer's disease, which is characterized by a loss of cholinergic neurons in certain areas of the brain. Conversely, increased ChAT activity is associated with the motor neuron disease Amyotrophic lateral sclerosis (ALS).

See also

• Acetylcholine
• Neurotransmitter
• Alzheimer's disease
• Amyotrophic lateral sclerosis