Computing on actin bundles network

Abstract

Actin filaments are conductive to ionic currents, mechanical and voltage solitons. These travelling localisations can be utilised to generate computing circuits from actin networks. The propagation of localisations on a single actin filament is experimentally unfeasible to control. Therefore, we consider excitation waves propagating on bundles of actin filaments. In computational experiments with a two-dimensional slice of an actin bundle network we show that by using an arbitrary arrangement of electrodes, it is possible to implement two-inputs-one-output circuits.

Actin droplet machine

“…Later, we realized that it might be unrealistic to expect someone to initiate and record travelling localizations (solitons, impulses) on a single actin filament. Therefore, we developed a numerical model of spikes propagating on a network of actin filament bundles and demonstrated that such a network can implement Boolean gates [33].…”

“…We demonstrated how to discover logical gates on a two-dimensional slice of the actin bundle network by representing Boolean inputs and outputs as spikes of the network activity. In a previous paper [33], we demonstrated, using numerical integration of FitzHugh–Nagumo model, that a two-dimensional actin network realized k -ary Boolean functions G : {0, 1} k → {0, 1}, when k input electrodes and one output electrodes are employed.…”

“…Our approach-computing with excitation waves propagating on overall 'density' of the conductive material-has previously been presented by us in [33]. As conductive material we looked at networks of actin bundles which were arranged by crowding effects without the need of additional accessory proteins [10,11].…”

“…We also offer an alternative to a numerical integration used in [33]: an automaton model of a threedimensional actin network. There is a substantial body of evidence confirming that automaton models are sufficient and appropriate discrete tools for modelling dynamics of spatially extended nonlinear excitable media [34][35][36], propagation [37], action potential [38,39], electrical pulses in the heart [40][41][42].…”

On Boolean gates in fungal colony

“…9. This is accompanied by distributions of gates discovered in experimental laboratory reservoir computing with slime mould Physarum polycephalum [34], succulent plant [11] and numerical modelling experiments on computing with protein verotoxin [2], actin bundles network [12], and actin monomer [3]. All the listed distributions have very similar structure with gates selecting one of the inputs in majority, followed by or gate, not-and an and-not gates.…”