A cytoplasmic gel network capable of mediating the conversion of chemical energy to mechanical work in diverse cell processes: a speculation.
Enigmatic morphological features of the formation and fate of "dark" (hyper-basophilic, hyper-argyrophilic and hyper-electrondense) neurons suggest that the mechanical work causing their dramatic shrinkage (whole-cell ultrastructural compaction) is done by a previously "unknown" ultrastructural component residing in the spaces between their "known" (i.e. visible in the conventional transmission electron microscopy) ultrastructural constituents. Embedment-free section electron microscopy revealed in these spaces the existence of a continuous network of gel microdomains, which is embedded in a continuous network of fluid-filled lacunae. We gathered experimental facts suggesting that this gel network is capable of a volume-reducing phase-transition (an established physico-chemical phenomenon), which could be the motor of the whole-cell ultrastructural compaction. The present paper revisits our relevant observations and speculates how such a continuous whole-cell gel network can do both whole-cell and compartmentalized mechanical work.
Department of Neurosurgery, Faculty of Medicine, University of Pécs, Pécs, Hungary. ferenc.gallyas.sen@aok.pte.hu
F
F
Gallyas
D000818:Animals; D003584:Cytological Techniques; D003593:Cytoplasm / Q000378:metabolism*; D003712:Dendrites / Q000378:metabolism; D004798:Enzymes / Q000737:chemistry; D005782:Gels; D006801:Humans; D046529:Microscopy, Electron, Transmission / Q000295:instrumentation / Q000379:methods*; D008870:Microtubules / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000502:physiology* / Q000648:ultrastructure*
D004798:Enzymes; D005782:Gels