---
title: "Removing ~1% of the bonds in a random elastic network produces protein-like allosteric response"
type: "claim"
status: "seedling"
writer_model: "claude-opus-4-8"
source_url: "https://arxiv.org/abs/1607.08562"
source_title: "Designing allostery-inspired response in mechanical networks"
source_author: "Jason W. Rocks, Nidhi Pashine, Irmgard Bischofberger, Carl P. Goodrich, Andrea J. Liu, Sidney R. Nagel"
source_date: 2017
source_venue: "PNAS 114(10):2520 (2017), 'Designing allostery-inspired response in mechanical networks' (arXiv:1607.08562)"
source_quote: "With nearly complete success, we are able to produce a strain between any pair of target nodes... by removing only ∼1% of the bonds... This targeted behavior is reminiscent of the long-range coupled conformational changes that often occur during allostery in proteins."
source_tier: 1
audit_status: "capture-verified — the hop capture (2026-07-11) records this as a Tier-1 primary with the exact quote preserved; the queen's independent re-fetch of arXiv:1607.08562 / PNAS 2017 was not run in this headless promotion. Freely fetchable on arXiv; clean re-read target. | AUDIT 2026-07-12 (claude-opus-4-8, cross-check): independent re-fetch of arXiv:1607.08562 confirms the quote verbatim and the citation 'Designing allostery-inspired response in mechanical networks', PNAS 114(10):2520–2525 (2017). Claim CONFIRMED. Removed a stray '</content>' closing tag left at the end of the note body (formatting hygiene)."
provenance: "Promotion from 10-inbox/raw/2026-07-11-hop-physical-learning-allostery.md, 2026-07-12"
origin: "batch"
derived_from: "10-inbox/raw/2026-07-11-hop-physical-learning-allostery.md"
date_created: "2026-07-12T00:00:00.000Z"
tags: ["allostery","metamaterials","soft-matter","mechanical-networks","structure-function","physical-learning","protein-biophysics"]
drafted_in: ["2026-07-13-cut-one-percent-of-the-bonds","cut-one-percent-of-the-bonds"]
---


Rocks, Pashine, Bischofberger, Goodrich, Liu, and Nagel (PNAS 2017; arXiv:1607.08562)
showed that a generic disordered spring network can be tuned into a long-range
mechanical machine by deleting a tiny fraction of its bonds. "With nearly complete
success, we are able to produce a strain between any pair of target nodes... by
removing only ∼1% of the bonds," and the resulting behavior "is reminiscent of the
long-range coupled conformational changes that often occur during allostery in
proteins." A local perturbation applied at one site produces a designed response at a
distant site — the defining signature of allostery — in a substrate with no biology
in it.

The cheapness is the load-bearing point. Because long-range response turns out to be
generic and easy to engineer in disordered networks, the authors offer the result as a
clue to biology: it "may give insight into why allostery is a common means for the
regulation of activity in biological molecules." The reading is that evolution reuses
allostery not because it is special or hard to build, but because the soft-mode
geometry that supports it is abundant and reachable by small changes — the trained
artifact and the evolved protein occupy the same mechanical regime. (This is an
interpretive extension the paper hedges as "may give insight," not a demonstrated
evolutionary claim.)

This is the empirical anchor for the cross-domain arc of the capture that seeded this
note. Node allostery is exactly the behavior a physical network can *learn* in situ by
a local rule ([[claim-coupled-learning-elastic-networks-compute-without-a-processor]]),
and the structure→function reading of such trained networks ties their task-critical
edges to slow collective modes
([[claim-physical-networks-become-what-they-learn-soft-modes]]). Together they frame a
protein as a physical learning machine on the same energy-based footing as the
Boltzmann / Forward-Forward lineage ([[claim-hinton-forward-forward-boltzmann-lineage]]),
and connect to [[backpropagation-gap]]'s question of whether shared structure implies
shared process.