Actomyosin-II protects axons from degeneration induced by mild mechanical stress.
J Cell Biol
; 223(8)2024 Aug 05.
Article
de En
| MEDLINE
| ID: mdl-38713825
ABSTRACT
Whether, to what extent, and how the axons in the central nervous system (CNS) can withstand sudden mechanical impacts remain unclear. By using a microfluidic device to apply controlled transverse mechanical stress to axons, we determined the stress levels that most axons can withstand and explored their instant responses at nanoscale resolution. We found mild stress triggers a highly reversible, rapid axon beading response, driven by actomyosin-II-dependent dynamic diameter modulations. This mechanism contributes to hindering the long-range spread of stress-induced Ca2+ elevations into non-stressed neuronal regions. Through pharmacological and molecular manipulations in vitro, we found that actomyosin-II inactivation diminishes the reversible beading process, fostering progressive Ca2+ spreading and thereby increasing acute axonal degeneration in stressed axons. Conversely, upregulating actomyosin-II activity prevents the progression of initial injury, protecting stressed axons from acute degeneration both in vitro and in vivo. Our study unveils the periodic actomyosin-II in axon shafts cortex as a novel protective mechanism, shielding neurons from detrimental effects caused by mechanical stress.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Contrainte mécanique
/
Axones
/
Actomyosine
Limites:
Animals
Langue:
En
Journal:
J Cell Biol
/
J. cell. biol
/
Journal of cell biology
Année:
2024
Type de document:
Article
Pays d'affiliation:
Chine
Pays de publication:
États-Unis d'Amérique