ULTIMATE COMPUTING - Quantum Consciousness Studies

Cytoskeleton/Cytocomputer 109
can undergo contraction and streaming which are important in cytoplasmic
movement such as amoeboid locomotion. The myosin appears to pull actin
filaments against each other. A rise in calcium ion causes a sharp drop in viscosity
of actin networks, through actin fragmenting proteins such as gelsolin. The same
rise in calcium activates myosin to pull actin filaments against one another,
resulting in gel contraction and vigorous streaming in adjacent “sol” regions.
George Oster (1984) of the University of California at Berkeley has described a
mechanism for amoeboid movement in which waves of calcium ion trigger
transient sol/gel ,regions. The net flow of material is towards the calcium flux,
which serves to pull the cell onward.
Figure 5.20: Components of the cytomatrix. Assembly of actin and related
proteins form cytoplasmic “gel” states. A) monomeric actin, B) assembled actin
filaments which are helical pairs of monomeric strands; center-cross section of
actin filament, C) the presence of filamin (dark strands) causes actin cross-linking
and dense “gel state,” D) calcium and/or actin fragmenting proteins causes
liquification to a “sol state.” By Paul Jablonka.
Cytomatrix structures give rise to amoeboid and other types of cytoplasmic
movement as well as polyhedral structures. Calcium mediated sol-gel transition
and gel contraction can be important in many cell functions, including perhaps the
transient representation of short term information and memory within neurons.
5.4.3 Cytoplasmic Solid State
Molecules such as proteins and RNA are heterogeneously distributed
throughout cytoplasm and passively flow at rates below that expected for normal
diffusion. Actively transported molecules such as those carried by axoplasmic
transport travel at velocities far in excess of diffusion. Initially, the slow diffusion