TY - JOUR
T1 - Myelin basic protein dynamics from out-of-equilibrium functional state to degraded state in myelin
AU - Ciasca, Gabriele
AU - Di Gioacchino, Michael
AU - Bianconi, Antonio
AU - Burghammer, Manfred
AU - Bruni, Fabio
AU - Campi, Gaetano
PY - 2020
Y1 - 2020
N2 - Living matter is a quasi-stationary out-of-equilibrium system; in this physical condition, structural fluctuations at nano- and meso-scales are needed to understand the physics behind its biological functionality. Myelin has a simple ultrastructure whose fluctuations show correlated disorder in its functional out-of-equilibrium state. However, there is no information on the relationship between this correlated disorder and the dynamics of the intrinsically disordered Myelin Basic Protein (MBP) which is expected to influence the membrane structure and overall functionality. In this work, we have investigated the role of this protein structural dynamics in the myelin ultrastructure fluctuations in various conditions, by using synchrotron Scanning micro X Ray Diffraction and Small Angle X ray Scattering. We have induced the crossover from out-of-equilibrium functional state to in-equilibrium degeneration changing the pH to values far from physiological condition. The observed compression of the cytosolic layer thickness probes that the intrinsic large MBP fluctuations preserve the cytosol structure also in the degraded state. Thus, the transition of myelin ultrastructure from correlated to uncorrelated disordered state, is principally affected by the deformation of the membrane and extracellular domain.
AB - Living matter is a quasi-stationary out-of-equilibrium system; in this physical condition, structural fluctuations at nano- and meso-scales are needed to understand the physics behind its biological functionality. Myelin has a simple ultrastructure whose fluctuations show correlated disorder in its functional out-of-equilibrium state. However, there is no information on the relationship between this correlated disorder and the dynamics of the intrinsically disordered Myelin Basic Protein (MBP) which is expected to influence the membrane structure and overall functionality. In this work, we have investigated the role of this protein structural dynamics in the myelin ultrastructure fluctuations in various conditions, by using synchrotron Scanning micro X Ray Diffraction and Small Angle X ray Scattering. We have induced the crossover from out-of-equilibrium functional state to in-equilibrium degeneration changing the pH to values far from physiological condition. The observed compression of the cytosolic layer thickness probes that the intrinsic large MBP fluctuations preserve the cytosol structure also in the degraded state. Thus, the transition of myelin ultrastructure from correlated to uncorrelated disordered state, is principally affected by the deformation of the membrane and extracellular domain.
KW - Myelin
KW - Myelin basic protein
KW - Nanoscale fluctuations
KW - Out-of-equilibrium biological systems
KW - Scanning micro X ray diffraction
KW - Small angle X ray scattering
KW - Myelin
KW - Myelin basic protein
KW - Nanoscale fluctuations
KW - Out-of-equilibrium biological systems
KW - Scanning micro X ray diffraction
KW - Small angle X ray scattering
UR - http://hdl.handle.net/10807/155257
U2 - 10.1016/j.bbamem.2020.183256
DO - 10.1016/j.bbamem.2020.183256
M3 - Article
VL - 1862
SP - 183256-N/A
JO - BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES
JF - BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES
SN - 0005-2736
ER -