The Cell Is Not A Bag Of Water, It Is An Elastic Gel

haidut

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I have been noticing for some time that modern science has been warming up to many of the ideas Peat has been writing about. This latest study coming from Harvard (the bastion of dogma) shows that the model of the cell as bag of randomly moving water is slowly coming to an end. The old model is being replaced by the "new" idea of the cell being an elastic gel, whose motion is controlled by the energetic state of the cell. Hyperactive (lower energy) cells are associated with disease such as cancer. Unfortunately, it seems that science is still holding onto the idea of random movement (even in a gel-like cell) but I think this is due to the fear of science admitting that cells may show self-organization and thus raise the question of cell consciousness.
Either way, I think there is some light at the end of the tunnel but the question is how quickly will these ideas get assimilated into mainstream medicine to start making a difference in practical therapies.

http://phys.org/news/2014-08-cell-ocean-buffeting.html

"...Conventional wisdom holds that the cytoplasm of mammalian cells is a viscous fluid, with organelles and proteins suspended within it, jiggling against one another and drifting at random. However, a new biophysical study led by researchers at Harvard University challenges this model and reveals that those drifting objects are subject to a very different type of environment. The cytoplasm is actually an elastic gel, it turns out, so it puts up some resistance to simple diffusion. But energetic processes elsewhere in the cell—in the cytoskeleton, especially—create random but powerful waves in the cytoplasm, pushing on proteins and organelles alike. Like flotsam and jetsam buffeted by the wakes of passing ships, suspended particles scatter much more quickly and widely than they would in a calm sea.

"...Guo, Weitz, and their collaborators tested this theory through a series of "knockout" experiments in which they removed the cells' fuel source, adenosine triphosphate (ATP). In the starved cells, suspended particles and endogenous organelles traveled far more slowly."

"..."The conclusion that the cytoplasm is best modeled as an elastic gel, out of equilibrium, rather than as a Brownian-based fluid has important implications," she says. "It means that factors modulating the stiffness and motion of the cytoplasm derive from the cell's underlying energetic state." The research team observed this in practice when they measured and compared the cytoplasmic forces within benign and malignant breast cells. The hyperactive malignant cells exhibited much stronger aggregate forces. In short, changes in the activities of molecular motors and other enzymatic activity can affect cellular properties like the stiffness of the cytoplasm and how easily objects can move within it. Cytoplasmic changes might then affect other cellular activities, further downstream. Future studies using force spectrum microscopy may shed new light on the elastic properties of both the cytoplasm and the nucleoplasm, and how these properties affect gene expression, metabolic signaling, cell growth, and motility."
 

aguilaroja

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haidut said:
http://phys.org/news/2014-08-cell-ocean-buffeting.html
...holding onto the idea of random movement (even in a gel-like cell) but I think this is due to the fear of science admitting that cells may show self-organization...

Here's the link to the journal article summary:

http://www.cell.com/cell/abstract/S0092 ... %2900924-6
"Highlights
•Random intracellular motion is driven by active force fluctuations in the cytoplasm
•The aggregate random forces enhance motion of small proteins and large organelles
•We develop force spectrum microscopy to probe aggregate random cytoplasmic forces
•The aggregate random forces are larger in malignant cancer cells than benign cells

"Summary
"Molecular motors in cells typically produce highly directed motion; however, the aggregate, incoherent effect of all active processes also creates randomly fluctuating forces, which drive diffusive-like, nonthermal motion. Here, we introduce force-spectrum-microscopy (FSM) to directly quantify random forces within the cytoplasm of cells and thereby probe stochastic motor activity. This technique combines measurements of the random motion of probe particles with independent micromechanical measurements of the cytoplasm to quantify the spectrum of force fluctuations. Using FSM, we show that force fluctuations substantially enhance intracellular movement of small and large components. The fluctuations are three times larger in malignant cells than in their benign counterparts. We further demonstrate that vimentin acts globally to anchor organelles against randomly fluctuating forces in the cytoplasm, with no effect on their magnitude. Thus, FSM has broad applications for understanding the cytoplasm and its intracellular processes in relation to cell physiology in healthy and diseased states."

I have not yet read the full article. As haidut mentions, the new data improves on previous dogma while asserting (cell) machinery relieves passive randomness. The cited news service article says:"the operations of cellular machinery prevent suspended particles from settling into equilibrium." I don't know this group's work well. David A. Weitz is prolific, with hundreds of journal articles with interesting topics. The view of a cell machine stirring up particle like a jacuzzi would seem to segue easier into commercial applications than, say, Gilbert Ling's notions of an energized intelligent association-induction array of polarized multilayers.

A more artistic person than me might find dissonance between themes of motorized agitation and "...unique living chemical structure that mediates long-distance information and energy transfer, hence the pervasive coherence that distinguishes life" (http://www.gilbertling.org/PCP39-2_ling.pdf)

http://www.ncbi.nlm.nih.gov/pmc/article ... 830583.pdf
J Cell Biol. 2008 Nov 17;183(4):583-7. doi: 10.1083/jcb.200806149. Cytoplasmic diffusion: molecular motors mix it up. Brangwynne CP1, Koenderink GH, MacKintosh FC, Weitz DA.
"the cytoplasm also undergoes constant agitation caused by the activity of molecular motors and other nonequilibrium cellular processes."

http://www.gilbertling.org/pdf/associat ... -words.pdf
"Thus in most living cells like muscle, nerve and red blood cell with a single type of cell membrane, it is superfluous to postulate a sodium pump to keep the cell level of Na+ low. Dynamically structured water does it perfectly without continued energy expenditure,..."
 
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If the work was done at Harvard, then it is one reductionist dogma vying to supplant another. This is how the corrupt patrimony covers up its mistakes, no matter how glaring, by feigning some shiny new bauble of a theory, cloaked in ersatz mathematics that proves nothing. It's tragic to think that mankind and even nature herself depends for its very sustenance on egomaniacal monsters such as these.
 
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<<Max Schultze pronounced in 1861 that a living cell is “a membrane-less
lump of protoplasm containing a nucleus">>

"pulpy, homogeneous, gelatinous substance" (Dujardin, 1835)

"the cytoplasm is best modeled as an elastic gel, out of equilibrium" (Lippincott-Schwartz, 2014) (it's only true after Harvard says it)

Still a while away from association-induction though. I have Gerald Pollack's book which is basically a microbiology textbook from 2050 and I payed it about a tenth of a college method.
 

StephanF

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I gave a presentation on Gilbert's and Pollack's work and contrasted the gel-like nature of the bound water in the cell to the highly stabilized colloidal system of water in the blood, due to the Zeta Potential explained by Thomas M. Riddick and Dr. T.C. McDaniel. There I presented the following picture about the current view (in medicine/biology) of the cell ('a bag of water'):


prodibio_-_poisson_sac_0.jpg


Better even is this picture, 'oh no, the cell is leaking':

bag-cry-fish-sad-face-water-Favim.com-227695.jpg


Great topic! :lol:
 
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StephanF said:
I gave a presentation on Gilbert's and Pollack's work and contrasted the gel-like nature of the bound water in the cell to the highly stabilized colloidal system of water in the blood, due to the Zeta Potential explained by Thomas M. Riddick and Dr. T.C. McDaniel. There I presented the following picture about the current view (in medicine/biology) of the cell ('a bag of water'):


prodibio_-_poisson_sac_0.jpg


Better even is this picture, 'oh no, the cell is leaking':

bag-cry-fish-sad-face-water-Favim.com-227695.jpg


Great topic! :lol:

Upload it will ya :mrgreen: I made one that summarizes the first chapters of Cells, Gels but it's in Italian (school work).
 

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