biology

Muscarinic acetylcholine receptor M4

Muscarinic acetylcholine receptor M4 is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Muscarinic acetylcholine receptor M4 rather than just read about it. In short: The muscarinic acetylcholine receptor M4, also known as the cholinergic receptor, muscarinic 4 (CHRM4), is a protein that, in humans, is encoded by the CHRM4 gene. Function M4 muscarinic receptors are coupled to Gi/o heterotrimeric proteins.

Key takeaways

Muscarinic acetylcholine receptor M4 belongs to biology; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Muscarinic acetylcholine receptor M4 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Muscarinic acetylcholine receptor M4 from memory before moving on to harder problems.

Reference excerpt

The muscarinic acetylcholine receptor M4, also known as the cholinergic receptor, muscarinic 4 (CHRM4), is a protein that, in humans, is encoded by the CHRM4 gene.

Function M4 muscarinic receptors are coupled to Gi/o heterotrimeric proteins. They function as inhibitory autoreceptors for acetylcholine. Activation of M4 receptors inhibits acetylcholine release in the striatum. The M2 subtype of acetylcholine receptor functions similarly as an inhibitory autoreceptor to acetylcholine release, albeit functioning actively primarily in the hippocampus and cerebral cortex. Muscarinic acetylcholine receptors possess a regulatory effect on dopaminergic neurotransmission. Activation of M4 receptors in the striatum inhibit D1-induced locomotor stimulation in mice. M4 receptor-deficient mice exhibit increased locomotor simulation in response to D1 agonists, amphetamine and cocaine. Neurotransmission in the striatum influences extrapyramidal motor control, thus alterations in M4 activity may contribute to conditions such as Parkinson's disease. The M4 muscarinic receptor has been found to be a regulator of erythroid progenitor cell differentiation. Inhibition of the M4 muscarinic receptor provides therapeutic benefits in myelodysplastic syndrome and anemia.

Ligands

Agonists Acetylcholine Carbachol CMI-936 Direclidine (NBI-1117568; HTL-0016878) GXV-813 (EX-A8078) ML-007 Oxotremorine Xanomeline (+trospium) Clozapine

Positive allosteric modulators Emraclidine (CVL-231, PF-06852231) LY-2033298 NS-136 SUVN-L3307032 VU-0152100 (ML-108) VU-0152099

Antagonists AFDX-384 (mixed M2/M4 antagonist, N-[2-[2-[(Dipropylamino)methyl]-1-piperidinyl]ethyl]-5,6-dihydro-6-oxo-11H-pyrido[2,3-b][1,4]benzodiazepine-11-carboxamide, CAS# 118290-27-0) Dicycloverine Diphenhydramine Himbacine Mamba toxin 3 ML-021 NBI-1076968 NBI-1076986 PD-102,807 (3,6a,11,14-Tetrahydro-9-methoxy-2-methyl-(12H)-isoquino[1,2-b]pyrrolo[3,2-f][1,3]benzoxazine-1-carboxylic acid ethyl ester, CAS# 23062-91-1) PD-0298029 Tropicamide - moderate selectivity over other muscarinic subtypes (2-5x approx) VU6028418

See also Muscarinic acetylcholine receptor

References

Illustrations

Worked examples

Example 1 — a first encounter with Muscarinic acetylcholine receptor M4

Start with the simplest possible case. Write down what Muscarinic acetylcholine receptor M4 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Muscarinic acetylcholine receptor M4 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Muscarinic acetylcholine receptor M4 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Muscarinic acetylcholine receptor M4

In research: Muscarinic acetylcholine receptor M4 appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Muscarinic acetylcholine receptor M4 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Muscarinic acetylcholine receptor M4 is common in secondary-school and first-year university syllabi. It links to neighbouring topics G protein-coupled receptors, Genes on human chromosome 11, Human proteins, so understanding it makes those chapters shorter.
In everyday life: Look for Muscarinic acetylcholine receptor M4 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Muscarinic acetylcholine receptor M4” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Muscarinic acetylcholine receptor M4 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Muscarinic acetylcholine receptor M4 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Muscarinic acetylcholine receptor M4 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Muscarinic acetylcholine receptor M4 in simple terms?

The muscarinic acetylcholine receptor M4, also known as the cholinergic receptor, muscarinic 4 (CHRM4), is a protein that, in humans, is encoded by the CHRM4 gene. Function M4 muscarinic receptors are coupled to Gi/o heterotrimeric proteins.

Why does Muscarinic acetylcholine receptor M4 matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Muscarinic acetylcholine receptor M4?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Muscarinic acetylcholine receptor M4.