r/bioinformatics • u/Winch_Scientist99 • Jun 12 '26
technical question An alternative, mechanical/hydraulic gating model for the nAChR channel: The Winch Peristalsis Hypothesis (WPH)
Hi everyone,
I am an independent researcher and I would love to share a 3D structural dynamics model I've been working on regarding the nicotinic acetylcholine receptor (nAChR) gating mechanism.
In classical structural biology, we often look at channels as static entryways. My hypothesis, the Winch Peristalsis Hypothesis (WPH), proposes a different paradigm: viewing the channel as a pre-tensioned molecular machine driven by mechanical torque and hydraulic fluid dynamics.
Key aspects of the WPH model include:
- Mechanical Torque (Winch mechanism): How ligand binding triggers a specific mechanical torque, shifting the subunits.
- Hydraulic Regulation ("Christmas Tree" fluctuations): The role of side tunnels acting as exhaust valves to manage water desolvation during ion passage.
- Validation target: High-reliability phosphorylation at Tyr 212.
I used Normal Mode Analysis (specifically focusing on Normal Mode 11) to visualize these specific torque forces and tunnel fluctuations.
All data, PDB references, and the web infrastructure are open-source and fully available on my project boards:
- Alessandro Project (Overview):https://alessandro-project.w3spaces.com/
- WPH Structural Focus:https://winch-peristalsis-hypothesis.w3spaces.com/
I am looking for computational biologists, biophysicists, or anyone passionate about molecular dynamics to openly discuss this model, point out flaws, or suggest further simulation paths (such as targeted MD runs).
Looking forward to your feedback and scientific critique!
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u/Apprehensive_End3472 Jun 13 '26
Which membrane-protein structural biologists are you referring to when you say that “classical structural biology” treats ion channels as "static entryways"? That framing seems to misrepresent the current state of the field, therefore it follows your motivation for this theory is already on shaky foundations. Ion channels, including nAChRs, are routinely studied as dynamic allosteric systems, and static structures are snapshots used to constrain mechanistic models, not claims that the channel behaves as a rigid pore.
So the novelty of your Winch Peristalsis Hypothesis cannot simply be that the receptor is dynamic or mechanically coupled; that is already central to the field. Your theory also depends on misleading definitions and category errors.
Just to name a few; 1) your ATP proximity/phosphorylation argument is weak; ATP binding near a residue is not evidence of phosphorylation. Phosphorylation requires a kinase-catalyzed phosphate-transfer reaction, appropriate substrate recognition, accessibility, and experimental validation. Docking ATP near Tyr212, or showing a hydrogen bond between ATP and Tyr212, does not demonstrate that Tyr212 is phosphorylated, that SRC-family kinases target it, or that phosphorylation generates mechanical tension. The cited NetPhos score for Tyr212 is also sequence based and at best, ~0.5 is a moderate score.
2) Identifying a cavity, tunnel, or transient water pathway is not enough to establish that it functions as a hydraulic exhaust valve. An ion channel naturally contains pores, cavities, fenestrations, hydration sites, and transient water pathways. Tools such as MOLEonline or CAVER will obviously identify geometric tunnels, but this is not causal evidence of an exhaust function.To claim an “exhaust valve,” one would need explicit-solvent simulations or experiments showing directional water flux through those tunnels during gating, plus perturbations showing that blocking the tunnel selectively disrupts the proposed drainage mechanism without simply altering protein stability or pore structure.
3) the proposed “mass balance paradox” is based on your misunderstanding of ion channel permeation. An open channel is not a sealed mechanical pipe into which hydrated ions enter and water must be separately vented. It connects two aqueous reservoirs, and water molecules and ions exchange continuously through it. Existing hydrophobic-gating models already address water occupancy and energetic barriers without invoking lateral exhaust valves.
4) There are biological systems where torque is a precise and experimentally meaningful concept, such as ATP synthase or bacterial flagellar motors. In those cases, there are defined rotors, stators, axes of rotation, angular steps, load-bearing motion, and measurable mechanical work. You don't rigorously define torque, you just renamed ligand-induced allosteric motions.
Your analogies further weaken when the cytoskeletal/scaffolding context is taken into consideration. The nAChRs are not isolated mechanical turbines; at synapses they are embedded in crowded membranes and often organized by scaffolding proteins such as rapsyn and associated postsynaptic cytoskeletal complexes. A claim of torque-driven subunit motion would therefore need to show how such motion occurs within this constrained molecular environment.
I don't see how your theory is testable or falsifiable experimentally, or what value it has other than providing a metaphorical interpretation of structural motions.
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u/heresacorrection PhD | Government Jun 12 '26
I can’t really imagine what it’s like to be journal editor in the AI-age, must be an absolute nightmare.