Fractal Scaling of Cortical Matter, Amyloid Fragmentation and Plaque Formation across Rodents and Primates

TL;DR

This paper investigates the fractal scaling and thermodynamic properties of amyloid proteins across rodents and primates, linking molecular changes to cortical connectivity and plaque formation.

Contribution

It introduces a thermodynamic framework to analyze protein structural changes and their relation to brain connectivity and disease across species.

Findings

Amyloid fragmentation correlates with cortical connectivity differences.

Fractal and unfolding thermodynamic scales describe protein activity.

Species-specific plaque formation is linked to thermodynamic properties.

Abstract

Thermodynamic tools are well suited to connecting evolution of protein functionalities to mutations of amino acid sequences, especially for neuronal network structures. These tools enable one to quantify changes in modular structure and correlate them with corresponding changes in observable properties. Here we quantify modular rodent-primate changes in amyloid precursor protein A4 and \b{eta} amyloid fragments. These are related to changes in cortical connectivity and to the presence (absence) of plaque formation in primates (rodents). Two thermodynamic scales are used, descriptive of water/air protein unfolding (old), or fractal conformational restructuring (new). These describe complementary aspects of protein activity, at respectively higher and lower effective temperatures.