Radical Pair Mechanism and the Role of Chirality-Induced Spin Selectivity during Planaria Regeneration: Effect of Weak Magnetic Field on ROS levels

Planarian is an intriguing model system wherein the effect of electric and magnetic fields can be studied on various biochemical pathways during cell morphogenesis. Recent experimental observations have demonstrated the non-trivial modulation of reactive oxygen species (ROS) levels by a weak magnetic field during planaria regeneration. However, the underlying biophysical mechanism behind this remains elusive. In this paper, we study the radical pair mechanism to explain the effect of weak magnetic fields on ROS modulation during planaria regeneration to explain the experimental results. We also investigate the effect of chirality-induced spin selectivity (CISS) on ROS levels by including it in the framework of the radical pair mechanism. We conclude that the inclusion of CISS explains the experimental results better and allows the radical pair model to have more parametric space to satisfy the experimental constraints. This study explains the crucial process of ROS modulation by the weak magnetic field with and without CISS, thereby paving the way to unraveling the vast domain of ROS modulation for desired outcomes.