Is consciousness to be found in quantum processes in microtubules?

[Write4U]

(you may copy n paste my post to your thread on the subject if you like please could you ?)

Done.

 

[RainbowSingularity]

Done

liked

 

[Write4U]

fyi
i am quite fascinated by your theory;

"emergent consciousness from the microtubule network"

it "feels" like it has a vast amount of relevant factual construct to it even if the finer precise point may be potentially un-definable

This is where I like Tegmark's suggestion that rather than asking the hard question which we don't even know how to pose, we should start with hard facts such as the fact that we have consciousness and we know quite a bit as to how it behaves and how we can control it in several ways.
We have ever-increasing accurate maps and now that we are able to look deep into nano-scale physics, we can gather statistical data on hard facts,

It is inevitable that with enough statistical data some patterns will begin to emerge that will point to some common denominators in the various stages and levels of emergent consciousness.

soo many of my fringe science notes & side plates are getting lit up by this the more i postulate the ethereal holistic imagery

Exactly, there is already overwhelming evidence that proto-consciousness begins very early on in single-celled organisms that lack brains or neural networks, but do possess microtubule networks (cytoskeletons) that control all the dynamic behaviors of these rudimentary forms of life. Apparently, this is what intrigued Penrose. Does the cytoskeleton have memory and reactive plasticity in response to external pressures?

↑ "clever"

imagine quantum computers oscillating at this level but with waves of variance running over them like waves in the sea effecting change which defines difference in process function it creates randomness variance to define potential frequency shift to potential life creation as a conscious binding attribute it lives as long as it's powered. Its personality is complex & varied

Yes, this is where the terms like "orchestrated objective reduction", "integrated information" , and "general correlation" begin to address the known "hard facts".

it all makes perfect sense. pure logic running like rainbow colours all interacting with butterfly effects affecting other tubes & functions

I agree, unless there is something that has escaped me completely, I see a perfectly logical direction of concerted research and data sharing.

I have quoted David Bohm before that science has become so specialized that much of it has become fractured and the left hand doesn't know what the right hand is doing.

There are literally hundreds, if not thousands of scientists studying brain function and whereas there are many groups doing outstanding work, there is very little "orchestrated coordination" by all these brilliant minds.

That is an ironic twist.

i guess the difference is when you press the brain with your finger on one point drugs impact what ever does it change the personality ? does it change the function as well as the over all aspect ?
is the action absorbed by the greater over all function ?

All these questions are being investigated from what I see. The real question is how much is shared with others so that duplicate research can be avoided and that from all the results the models will "emerge" all by themselves, along with more "integrated" knowledge.

 

[Bells]

Mod Note

Do you realize how stupid this remark is?

We have consciousness and regardless of how consciousness manifests itself, we do NOT now have world peace!
So where is the fundamental logic contained in the observation that I would claim emergent consciousness from the microtubule network might solve the question of world peace ?

If you are going to use "clever" sarcasm, at least try to maintain a level of common sense, if not scientific objectivity.

As it stands it makes you the fool, not me.

None of which has to do with COVID19, this discussion or the OP:

Hello all,
Greetings!

Covid-19 is not yet fully clear so many many thoughts keep on brainstorming us, logically. I have these confusions and questions. :-

1. Antibodies against this virus said to persist in body for 4-6+ months or so either post infection or
post-vaccination. My confusion is, how these antibodies persist for so long. Is it its natural and normal
lifespan or it has some yet unclear purpose ?If later, what can it be?

Also can such persistence of antibodies in our body be also harmful since cultural targets were to develop Immunological Memory based immunity instead of long existing antibody based immunity.

2. Many Medication or vaccines may be based on disturbing normal/natural activities of Virus esp. intra-cellular after infection of virus into the host cells. May it be by inactivated virus based vaccine or by interfering the normal activities of virus, replications etc. i.e disturbing the RNA or genome of virus. As felt, Virus is live once it is intra-cellular and its genome is really effective for its growth. Whole virus is not needed for such purpose. If so then, can it become a reason to
get its variant or new form by such changed genome? I mean, can disturbing genome natural structure or activity of Covid-19 Virus lead to new variants or even new type of virus?

Pls contribute.

Best wishes.

You have thrown yet another thread completely off topic because you cannot help yourself but to talk about your pet obsession.

The sad part is that microtubules, particularly in various inhibiting drugs when it comes to cancer, is actually quite interesting. But no one will ever want to discuss it here because you would completely flood the thread or discussion with consciousness crap, as you are doing in this thread.. Which is about COVID19.. And what do you do? Find the first opportunity to bring in microtubules and consciousness. You cannot help yourself. You have an entire thread dedicated to microtubules. Keep it all contained there.

 

[Write4U]

The sad part is that microtubules, particularly in various inhibiting drugs when it comes to cancer, is actually quite interesting.

But nothing to do with how viruses propagate? OK

This is my last post in this thread.

Does cancer work like a virus?

Cancer cells force normal cells to mimic viruses to help tumors spread, resist treatment

Summary: In a study that could explain why some breast cancers are more aggressive than others, researchers say they now understand how cancer cells force normal cells to act like viruses -- allowing tumors to grow, resist treatment, and spread.

The virus mimic is detected in the blood of cancer patients, particularly in cases of an aggressive type known as triple-negative breast cancer. Researchers say cracking the code of how this process works opens up the possibility of targeting this mechanism for treatment.
Jul 13, 2017

https://www.sciencedaily.com/releases/2017/07/170713165435.htm

click.

 

[exchemist]

...............[blah blah blah]............

click.

This is quite funny, as one thing it is impossible to do is to put a moderator on Ignore.

 

[Bells]

Mod Note

Let's keep the flaming and trolling out of the thread.

 

[Write4U]

This is an example of in-depth research in neural brain processes. Remarkable that microtubules that do all hard work are never mentioned. A perfect example of fractured research in a common area of interest.

A new way to capture the brain’s electrical symphony

How voltage readings from individual neurons could power the next revolution in neuroscience
Neuroscientists have tried for decades to observe the swift electrical signals that are a major component of the brain’s language. Although electrodes, the workhorse for measuring voltage, can reliably record the activity of individual neurons, they struggle to capture the signals of many, particularly for prolonged periods.

But in the past two decades, scientists have found a way to embed fluorescent, voltage-indicating proteins right into the cell membranes of neurons. With the right kind of microscope, they can then see cells lighting up as they talk to each other — be it in a whisper or a shout. Voltage imaging can also record electrical chatter between many neurons at once, and then average those signals across large chunks of brain tissue. This helps researchers to study the brain’s electrical activity across different spatial scales, by listening not only to the voices of individual cells but also to “the roar of the crowd”, Cohen says.

High-speed process

The average human brain contains about 120 billion neurons, which constantly receive and send information through branch-like appendages called dendrites. Chemical or electrical signals that reach the dendrites produce small voltage changes across the cell’s membrane, which are routed to the cell body.

When the sum of the voltage changes reaches a point of no return, called a threshold, the neuron fires a large electrical spike — an action potential. This jolt whizzes at speeds of up to 150 metres per second along a neuronal branch, known as an axon, to another set of branching appendages. Here, chemical or electrical signals pass the information on to the next set of dendrites.

Neuronal signals converge, diverge and synchronize to produce a symphony of thoughts, emotions, actions and reactions, from the flush of a face to a baby’s hiccup. But scientists’ listening tools are extremely limited.

ORCH OR, PHI IIT, PSII theories all propose a massive interconnected (orchestrated, integrated) neural network, which combined with the memory function enables the brain to acquire an emergent consciousness and implications of the sensory data from the environment.

First developed in the 1940s, miniature electrodes as thin as a hair can be inserted into the brain, up against or inside neurons, where they measure membrane voltage with precision and speed. But this approach can be used to monitor just one or a handful of neurons at once — and only for a limited amount of time, because the electrodes eventually damage the cell. It’s like trying to get the gist of an orchestral arrangement by following one player for a few seconds.

Bundles of micro-electrodes can record the electrical activity of up to 200 cells at once, but because these electrodes are placed near to neurons rather than inside them, they can detect only the action potentials, the sharpest spikes in electrical activity.

They are deaf to softer notes — the small electrical changes that do not push the neuron all the way to an action potential. These sub-threshold voltage changes are key to brain function, because they gradually add up to determine whether or not a neuron will fire.

All in the detail

So far, GEVIs have proved successful in tracking individual action potentials in both cultured neurons, grown in a dish, and in the intact brains of a wide range of animals, from insects5 to mice6. One of the biggest promises of the technique is its potential to record not only the big events but also the small, sub-threshold changes in membrane voltage that reflect the messages that a neuron receives from neighbouring cells.

Cohen says. “Voltage imaging lets you see the inputs to the neurons in vivo, which we had no way to look at previously,” he says.

Another advantage of GEVIs is that, unlike electrodes, which record mainly signals from the cell body, they can record electrical signals from any part of a nerve cell, right down to the tips of dendrites (see ‘Hitting the scales’). That’s like being able to listen specifically to the notes played by a pianist’s left hand. “This is something that I’ve been dreaming for a long time — and I’m not alone,” says Katalin Toth, a neurobiologist at Laval University in Quebec City, Canada. Many neuroscientists are striving to follow voltage across entire neurons to see how it changes in different regions of the cell, she says.

Getting a visual read-out of membrane voltage also allows scientists to see electrical signals that inhibit neuronal firing rather than trigger it. Because inhibitory signals are impossible to record with approaches such as calcium imaging, it’s unclear how exactly they shape brain activity, says Rosa Cossart, a neurobiologist at the Mediterranean Institute of Neurobiology in Marseilles, France.
https://www.nature.com/articles/d41586-018-06694-6

 

[Write4U]

Dendrites In Vitro and In Vivo Contain Microtubules of Opposite Polarity and Axon Formation Correlates with Uniform Plus-End-Out Microtubule Orientation

Abstract

In cultured vertebrate neurons, axons have a uniform arrangement of microtubules with plus-ends distal to the cell body (plus-end-out), whereas dendrites contain mixed polarity orientations with both plus-end-out and minus-end-out oriented microtubules. Rather than non-uniform microtubules, uniparallel minus-end-out microtubules are the signature of dendrites in Drosophila and Caenorhabditis elegans neurons. To determine whether mixed microtubule organization is a conserved feature of vertebrate dendrites, we used live-cell imaging to systematically analyze microtubule plus-end orientations in primary cultures of rat hippocampal and cortical neurons, dentate granule cells in mouse organotypic slices, and layer 2/3 pyramidal neurons in the somatosensory cortex of living mice.

In vitro and in vivo, all microtubules had a plus-end-out orientation in axons, whereas microtubules in dendrites had mixed orientations. When dendritic microtubules were severed by laser-based microsurgery, we detected equal numbers of plus- and minus-end-out microtubule orientations throughout the dendritic processes. In dendrites, the minus-end-out microtubules were generally more stable and comparable with plus-end-out microtubules in axons. Interestingly, at early stages of neuronal development in nonpolarized cells, newly formed neurites already contained microtubules of opposite polarity, suggesting that the establishment of uniform plus-end-out microtubules occurs during axon formation. We propose a model in which the selective formation of uniform plus-end-out microtubules in the axon is a critical process underlying neuronal polarization.

SIGNIFICANCE STATEMENT

Live-cell imaging was used to systematically analyze microtubule organization in primary cultures of rat hippocampal neurons, dentate granule cells in mouse organotypic slices, and layer 2/3 pyramidal neuron in somatosensory cortex of living mice

In vitro and in vivo, all microtubules have a plus-end-out orientation in axons, whereas microtubules in dendrites have mixed orientations. Interestingly, newly formed neurites of nonpolarized neurons already contain mixed microtubules, and the specific organization of uniform plus-end-out microtubules only occurs during axon formation. Based on these findings, the authors propose a model in which the selective formation of uniform plus-end-out microtubules in the axon is a critical process underlying neuronal polarization.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4728718/

 

[Write4U]

Is there a correlation between mathematically orchestrated neural functions and the emergence of intelligence?

Kelliher, Michael & Saunders, Harriet & Wildonger, Jill. (2019). Microtubule control of functional architecture in neurons. urrent Opinion in Neurobiology. 57. 39-45. 10.1016/j.conb.2019.01.003.

Neurons are exquisitely polarized cells whose structure and function relies on microtubules. Microtubules in signal-receiving dendrites and signal-sending axons differ in their organization and microtubule-associated proteins. These differences, coupled with microtubule post-translational modifications, combine to locally regulate intracellular transport, morphology, and function.

Recent discoveries provide new insight into the regulation of non-centrosomal microtubule arrays in neurons, the relationship between microtubule acetylation and mechanosensation, and the spatial patterning of microtubules that regulates motor activity and cargo delivery in axons and dendrites. Together, these new studies bring us closer to understanding how microtubule function is locally tuned to match the specialized tasks associated with signal reception and transmission.

...more
https://www.researchgate.net/figure...t-diverse-roles-within-neurons_fig1_334837860

Microtubules are highly dynamic structures, which consist of α- and β-tubulin heterodimers, and are involved in cell movement, intracellular trafficking, and mitosis.

In the context of cancer, the tubulin family of proteins is recognized as the target of the tubulin-binding chemotherapeutics, which suppress the dynamics of the mitotic spindle to cause mitotic arrest and cell death.[/quote]

Importantly, changes in microtubule stability and the expression of different tubulin isotypes as well as altered post-translational modifications have been reported for a range of cancers. These changes have been correlated with poor prognosis and chemotherapy resistance in solid and hematological cancers. However, the mechanisms underlying these observations have remained poorly understood.

Emerging evidence suggests that tubulins and microtubule-associated proteins may play a role in a range of cellular stress responses, thus conferring survival advantage to cancer cells. This review will focus on the importance of the microtubule–protein network in regulating critical cellular processes in response to stress. Understanding the role of microtubules in this context may offer novel therapeutic approaches for the treatment of cancer.

https://www.frontiersin.org/articles/10.3389/fonc.2014.00153/full

If this may seem somewhat irrelevant in context of consciousness, but it is not any specific function that microtubules perform, but all of the functions they perform and all relating to electrochemical data processing.

Now conceptualize an orchestrated neural network that processes electrochemical data with physically deterministic mathematical computative functions. If all these processes add up to the appearance of some form of unconscious but intelligent function, is it such a great leap to suggest an emergent awareness of all these functions in the form of integrated and orchestrating objective reduction into sentient thought processes, i.e. consciousness?

 

[Write4U]

Will these turn into AI?

https://7news-com-au.cdn.ampproject...ned-how-to-reproduce-scientists-say-c-4823775

Microtubule dynamics in Xenopus egg extracts
Abstract

The organization and function of microtubules change dramatically during the cell cycle. At the onset of mitosis, a radial array of microtubules is broken down and reorganized into a bipolar spindle. This event requires changes in the dynamic behavior of individual microtubules. Through the use of Xenopus laevis egg extracts, a number of proteins affecting microtubule behavior have been identified. Recently, progress has also been made towards understanding how the activities of such microtubule-affecting proteins are regulated in a cell cycle-dependent manner. It is hoped that understanding how microtubule behavior is controlled during the cell cycle in vitro may illuminate the role of microtubule dynamics in various cellular processes.

There is an extensive record of microtubules affording hunting and "eating" abilities in single celled organisms.

As the Xenopus experiement involved selection of specific body shapes (U shape) it stands to reason that this body type and behavior is facilitated by the cytoskeleton and microtubule motors of the Xenopus.

The evidence is just overwhelming. Microtubules are the common denominator in all "organelles" that afford single celled organisms to execute dynamic behaviors to maintain life!

Organelles are specialized structures that perform various jobs inside cells. The term literally means “little organs.” In the same way organs, such as the heart, liver, stomach, and kidneys, serve specific functions to keep an organism alive, organelles serve specific functions to keep a cell alive. May 23, 2019

Prc1E and Kif4A control microtubule organization within and between large Xenopus egg asters

The cleavage furrow in Xenopus zygotes is positioned by two large microtubule asters that grow out from the poles of the 1st mitotic spindle. Where these asters meet at the midplane they assemble a disc-shaped interaction zone consisting of anti-parallel microtubule bundles coated with chromosome passenger complex (CPC) and centralspindlin which in.. Download full-text

https://www.researchgate.net/public...and_between_large_Xenopus_egg_asters/download

The multifunctional spindle midzone in vertebrate cells at a glance
Article , Patricia Wadsworth, May 2021

During anaphase, a microtubule-containing structure called the midzone forms between the segregating chromosomes. The midzone is composed of an antiparallel array of microtubules and numerous microtubule-associated proteins that contribute to midzone formation and function. In many cells, the midzone is an important source of signals that specify the location of contractile ring assembly and constriction. The midzone also contributes to the events of anaphase by generating forces that impact chromosome segregation and spindle elongation; some midzone components contribute to both processes.

The results of recent experiments have increased our understanding of the importance of the midzone, a microtubule array that has often been overlooked. This Journal of Cell Science at a Glance article will review, and illustrate on the accompanying poster, the organization, formation and dynamics of the midzone, and discuss open questions for future research.

https://www.researchgate.net/public...indle_midzone_in_vertebrate_cells_at_a_glance

 

[Write4U]

An essential history of the evolution of consciousness.

 

[Write4U]

Live lecture:

 

[James R]

An essential history of the evolution of consciousness.

That's a very interesting read, if you're into octopuses. (I've read it.) I don't regard it as a history of consciousness. Also, I don't see how this connects to the thread topic. I don't recall the book mentioning microtubules, for example.

 

[Write4U]

That's a very interesting read, if you're into octopuses. (I've read it.) I don't regard it as a history of consciousness. Also, I don't see how this connects to the thread topic. I don't recall the book mentioning microtubules, for example.

That's odd, I read a clear narrative of the evolution from fundamental chemical response mechanisms to ever greater neural complexity and sensory acuity that must have led to the emergence of conscious awareness of self and environment.

I particularly was surprised to read that emergent consciousness followed two separate evolutionary paths in land-dwellers like humans and ocean-dwellers like the octopus, due to the completely incompatible environments requiring entirely novel survival techniques.

IMO it showed the awesome versatility in evolutionary processes as long as microtubules (neurons) are present.

I don't understand why you still reject the notion that microtubules are the single common denominator in all Eukaryotic lifeforms, both in the cellular cytoplasm and the neural networks of the body and brain, and even in plants for photosynthesis and distribution of energy throughout the leaves and stems.

Penrose was particularly interested in very simple single celled organism that did not have neural networks but did have cytoskeletons (microtubules) and were able communicate, coordinate, effect transport and navigation, mitosis and cell divisio, memory storage and recognition. If that is enough to pique a Nobel Prize winning scientist, who feels qualified to dismiss his curiosity as a waste of time?

That microtubules are the primary active organelles in electrochemical data processing and transport, is demonstrated fact. If this is not yet clear it is due to lack of interest and minimal study on the subject.

A brief overview:
Are Microtubules the Brain of the Neuron

Microtubules may be the brains of the cell, particularly neurons—operating like a computerized Lego set. They are large complex scaffolding molecules that work closely with the two other rapidly changing structural molecules, actin and intermediate filaments, to provide structure for the entire cell including the spatial placement of organelles.

In neurons, microtubules respond instantly to mental events and constantly build and take down elaborate structures for the rapidly changing axons and dendrites of the synapses. Some think that microtubules are quantum computers and the seat of consciousness. Their lifestyle is quite remarkable.

A previous post described elaborate functions along the neuron’s axon including special tagging of cargoes that are transported by distinct motors with complex ancillary molecules for each type of transport.

Microtubules are the basic structural elements for cell division. The centromere is a key structure holding chromosomes together. It connects with the kinetochore where microtubule based spindle fibers attach to the chromosomes. Centrioles produce microtubules that orchestrate the rearrangement and sorting of the DNA during the extremely elaborate process of cell division.

Complex arrangements of microtubules direct and pull all the elements of the division process through multiple phases. The structure for this process is considered the most complex machine ever discovered in nature and is based on microtubule actions.

Microtubules are critical for the neuron’s migration; for the polar structure of the dendrite, soma and axon; and for stem cell’s determination of the type of cell a neuron will become. They are highways for long distance transport of materials and organelles. They are dynamic and changeable with elaborate mechanical functions. They control the signaling at local regions of the extremely long axon.

Are Microtubules the Brain of the Neuron?

From Y tambe

The actions of microtubules are fantastically complex. They respond instantly in a vast amount of different ways to mental events in thousands of places throughout the neuron at once. How is this directed? How can anyone think that this is a random process? How can anyone not see that mental events direct these fantastically complex processes?

much, much more....... do take the time to read this comprehensive review of microtubule function.
https://jonlieffmd.com/blog/are-microtubules-the-brain-of-the-neuron

In reviewing your book, Ray Kurzweil has said that “cellular conversations might be related to the emergence of intelligence and consciousness.” What does your book imply about the definition of Life?

Life has been generally considered to be a cell or group of cells, with metabolic functions and the ability to reproduce. It has not been at all clear how to define consciousness or intelligence.

But, now we find that much of a cell’s function is to converse with other cells or internally signal among its own components. This back and forth directed communication now has to be included in a new definition of life and perhaps might be related to intelligence throughout evolution.

Everywhere we look, there are ubiquitous conversations among all cells in all organisms. Life might come down to the ability to converse, which is another way of saying life is based on the ability to transfer meaningful biological information.

https://jonlieffmd.com/category/blog/cellular-intelligence-blog

 

[James R]

Write4U:

IMO it showed the awesome versatility in evolutionary processes as long as microtubules (neurons) are present.

Can you find any mention of the word "microtubules" in the book? I don't recall any.

I don't understand why you still reject the notion that microtubules are the single common denominator in all Eukaryotic lifeforms, both in the cellular cytoplasm and the neural networks of the body and brain, and even in plants for photosynthesis and distribution of energy throughout the leaves and stems.

Eukaryotic lifeforms have lots of common denominators, so why you would single out microtubules would be a mystery, were it not for your record of fanboy devotion to them.

Penrose was particularly interested in very simple single celled organism that did not have neural networks but did have cytoskeletons (microtubules) and were able communicate, coordinate, effect transport and navigation, mitosis and cell divisio, memory storage and recognition. If that is enough to pique a Nobel Prize winning scientist, who feels qualified to dismiss his curiosity as a waste of time?

Penrose's interest in them was put forward at least 30 years ago, now, as a tentative hypothesis in a book that was mostly about something else.

I have not said that the study of microtubules is a waste of time, or anything like that. I have said that there's no good evidence for wild claims such as your ones that they are involved in memory, consciousness, recognition, coordination, etc. The vast majority of the sources you spam to this thread have nothing to do with any of that, either, even though this is your central thesis.

 

[Write4U]

Write4U:
Can you find any mention of the word "microtubules" in the book? I don't recall any.

The term neuron always includes microtubules. They are the heart of neurons and all cells for that matter. MT make up the cytoskeleton of ALL Eukaryotic organisms. Look it up!

Eukaryotic lifeforms have lots of common denominators, so why you would single out microtubules would be a mystery, were it not for your record of fanboy devotion to them.

Name the functional common denominators in ALL Eukaryotic organisms that are present in the trillions of dynamic data processing networks throughout the entire body, effectively making the entire body an extension of the central processor brain.

Penrose's interest in them was put forward at least 30 years ago, now, as a tentative hypothesis in a book that was mostly about something else.

Penrose was astounded that single cells without any neural network could still communicate via the cytoskeleton (microtubules) itself. It is that remarkable ability in single celled organisms that raised the question if microtubules are suitable for quantum processing of qubits. This is how the collaboration with Hameroff came about.
There is recent evidence that this might well be the case.

I have not said that the study of microtubules is a waste of time, or anything like that. I have said that there's no good evidence for wild claims such as your ones that they are involved in memory, consciousness, recognition, coordination, etc. The vast majority of the sources you spam to this thread have nothing to do with any of that, either, even though this is your central thesis.

And that is where you are wrong, due to willful refusal to put any serious research into the subject.

If you have access to Research Gate, check them out for serious and formal presentations of current state of research into the nanoworld of microtubules.

An off-hand example of the role microtubules in neuronal cells.

Guidance signaling downstream pathways involved in MT dynamics in the axon and GC I: MT-stabilizing, MT-destabilizing and MT-polymerization supporters.

MTs are shown as light purple tubes, F-actin as red lines. MAPs are represented in blue, kinases in yellow and MAP-interacting proteins in purple. Guidance cue receptors are in brown. Guidance-evoked responses are represented in green (attraction), red (repulsion) and orange (pause) arrows. MT advance and retraction are represented with green and red arrowheads, respectively.

With the Permission of Microtubules: An Updated Overview on Microtubule Function During Axon Pathfinding, Carlos Sanchez-Huertas, Eloísa Herrera

During the establishment of neural circuitry axons often need to cover long distances to reach remote targets. The stereotyped navigation of these axons defines the connectivity between brain regions and cellular subtypes. This chemotrophic guidance process mostly relies on the spatio-temporal expression patterns of extracellular proteins and the s... more...

Cite , Download full-text

https://www.researchgate.net/figure...-dynamics-in-the-axon-and-GC-I_fig2_356743838

 

[James R]

The term neuron always includes microtubules.

That's a "no", then. As I thought.

They are the heart of neurons and all cells for that matter. MT make up the cytoskeleton of ALL Eukaryotic organisms. Look it up!

As I understand it, they are structural components.

Name the functional common denominators in ALL Eukaryotic organisms that are present in the trillions of dynamic data processing networks throughout the entire body, effectively making the entire body an extension of the central processor brain.

You speak as if there are "dynamic data processing networks" throughout the entire body. What evidence do you have for data processing at the microtubule level (as opposed to the the neuronal level)? Anything?

If you have access to Research Gate, check them out for serious and formal presentations of current state of research into the nanoworld of microtubules.

It's not really my field of expertise, and I'm not that interested. I'm sure that researchers in the field will let us know if they ever discover any actual "data processing" or whatever.

 

[Write4U]

That's a "no", then. As I thought.

How odd. You accuse me of posting anything that has the word microtubule in it. Now you accuse me of posting about neurons that have microtubules in them but does not explicitly mention microtubules.

As I understand it, they are structural components.

Yes, you have an extremely limited understanding of microtubules and their importance.

You speak as if there are "dynamic data processing networks" throughout the entire body. What evidence do you have for data processing at the microtubule level (as opposed to the neuronal level)? Anything?

I anticipated that question for a long time now, demonstrating that you have no clue about the functions microtubules perform.

What do microtubules do in neurons?

Microtubules (MTs) are long cylindrical structures of the cytoskeleton that control cell division, intracellular transport, and the shape of cells. MTs also form bundles, which are particularly prominent in neurons, where they help define axons and dendrites. 9 Aug 2018

Bundles of Brain Microtubules Generate Electrical Oscillations
Abstract

Microtubules (MTs) are long cylindrical structures of the cytoskeleton that control cell division, intracellular transport, and the shape of cells.

MTs also form bundles, which are particularly prominent in neurons, where they help define axons and dendrites. MTs are bio-electrochemical transistors that form nonlinear electrical transmission lines.

However, the electrical properties of most MT structures remain largely unknown. Here we show that bundles of brain MTs spontaneously generate electrical oscillations and bursts of electrical activity similar to action potentials.

Under intracellular-like conditions, voltage-clamped MT bundles displayed electrical oscillations with a prominent fundamental frequency at 39 Hz that progressed through various periodic regimes. The electrical oscillations represented, in average, a 258% change in the ionic conductance of the MT structures. Interestingly, voltage-clamped membrane-permeabilized neurites of cultured mouse hippocampal neurons were also capable of both, generating electrical oscillations, and conducting the electrical signals along the length of the structure.

Our findings indicate that electrical oscillations are an intrinsic property of brain MT bundles, which may have important implications in the control of various neuronal functions, including the gating and regulation of cytoskeleton-regulated excitable ion channels and electrical activity that may aid and extend to higher brain functions such as memory and consciousness.

Introduction

MTs are unique components of the cellular cytoskeleton that form a wide variety of intracellular superstructures1. Highly polarized cells such as neurons, for example, present two structurally and

functionally distinct domains, namely a single long, thin axon and multiple shorter dendrites that either transmit or receive electrical signals, respectively. MT stability is at the center of the polarization process of neurons, which is fundamental to their development and plasticity, as well as the development of neurodegenerative diseases.

MTs form dense parallel arrays known as bundles in axons and dendrites, which are required for the growth and maintenance of neurites in neurons

2,3,4. The organization of MT bundles in axons and dendrites largely depends on the prevalent type of MT-associated proteins prevalent in them. MAP2, for example is mainly found in dendrites while tau is mainly found in axons3,5.

Another important aspect of MT organization and function relies on their remarkable and not as well understood biophysical properties. MTs are highly charged electrically polarized polymers, where their αβ tubulin heterodimeric units have a high electric dipole moment

6, rendering these structures highly sensitive to electric fields both in vitro7,8 and in vivo9. Large uncompensated charge10 present in MTs likely plays an important role in electrostatic interactions implicated in MT-macromolecular complexing11.

MTs are thought to generate oscillatory electric fields at expense of elasto-electrical vibrations

12, which may explain our findings that electrically-stimulated MTs behave as biological transistors behaving as sophisticated nonlinear transmission lines, capable of supporting the amplification and axial transfer of electrical signals 13,14,15,16,17,18. Within the cytoplasm MT-generated variable currents may contribute to the presence and modulation of large intracellular electric fields, which in turn, will help control cell function.

The above arguments support a potentially relevant role of electrical oscillations on brain MT bundles, which should be critical to neural function.

We recently reported that MT sheets sustain electrical oscillations19, which are driven by a permanent electrical polarization from local asymmetries in the ionic distributions between the intra- and extra-MT environments. Thus, the MT wall behaves as an electrical oscillator that produces oscillatory ionic currents with variable amplitude and periodicity depending on the driving force and ionic compositions, and is consistent with the periodic on-off switching of the nanopores. In this context, here we explored whether rat brain MT bundles do have electrical properties consistent with electrical oscillators. Our findings indicate that rat brain MT bundles generate a wide variety of endogenous electrical oscillations. Interestingly, the cytoskeleton of cultured adult mouse hippocampal neurons also supported electrical oscillations establishing an electrical role for brain MTs.

much more.......
https://www.nature.com/articles/s41598-018-30453-2[/quote]

It's not really my field of expertise, and I'm not that interested.

That is obvious.

I'm sure that researchers in the field will let us know if they ever discover any actual "data processing" or whatever.

Too bad you are not interested enough to read the state of knowledge about the role microtubules play in "data processing" at all levels and individual cells of all Eukaryotic organisms and in proto form in Prokaryotic organisms.
There is lots of fascinating information available on the roles microtubules play in both unconscious and conscious living organisms.

 

[Write4U]

What evidence do you have for data processing at the microtubule level (as opposed to the neuronal level)? Anything?

I am sure you know that neurons are cells. Microtubules in the cytoplasm are what form and control the structure and behavior of cells.

Axons can have as many as 100 bundles of microtubules in one axon cross section. There are many variations in these lattices with different types of stabilizing molecules, different orientations, and many different associated molecules and co factors. 29 Nov 2015

Microtubule Structures Shape the Entire Cell

When a neuron is being produced and while it migrates, it changes shape. Other shape changes occur frequently with new synapses both axons and dendrite spines (see post on Dendrite Spine Complexity). When a neuron migrates it produces a process in front, moves the nucleus to the front and then disassembles the process left in back.

Microtubules and actin scaffolding direct all of this.

The anchor in this process is the centrosome made of centrioles that are made of specific microtubules structures. It produces microtubule connections in the processes moving forward. The centrosome is the organizing center of the actions of microtubules. It is an organelle near the nucleus. Two centrioles at right angles are surrounded by a large protein mass. This very complex machine and directs cell division by pulling all elements of the division through many phases.

The centriole is a set of microtubules often arranged as a tubule with nine microtubules defining the circle. In some there are other microtubules in the center. (See post on the Primary Cilium for a discussion its centrioles). When centrioles connect, they do so at right angles and these pairs travel to opposite ends of the nucleus in the cell division process. Centrioles are involved in the organization of the mitotic spindle and in the completion of cytokinesis, or movement of the DNA in cell division.

From Kelvinsong

But, centrosomes, made of centrioles, are, also, the critical way the neuron organizes the spreading and constantly changing microtubule structure. In fact, the centriole determines where the nucleus sits in the cell as well as organizing spatial structure of organelles in the cell (golgi, endoplasmic reticulum, etc). In cells with cilia and flagella, the central centriole determines where it will be. This mother centriole is, also, called the basal body as the starting point of the cell’s entire microtubule process.

Microtubules make a large structure that surrounds the entire nucleus in a cage. This cage extends from the centrosome around the nucleus and into the leading process. These microtubules orchestrate the neuron’s ability to migrate. The tubule structure then pulls the centrosome with the nucleus into the leading edge.

When the axon starts and grows the cell’s shape becomes polar and asymmetric. The neurite (start of the axon) grows with bundles of microtubules and a very active actin growth cone. This complex process involves mechanical actions of both.

When the neuron becomes a specific type, microtubules take on very specific shapes and have to maintain these with unique stabilizing molecules. This involves very active transport of these stabilizing molecules by kinesin motors. How this is directed is not clear. It is possible that the centrosome and Golgi are involved. As the axon grows longer, many different stabilizing proteins are involved, such as +TIPs, interacting with actin, adhesion molecules, and the microtubules. At times an entire bundle of many microtubules are moved by mechanical forces from motors to allow for changes in shape. When injury to the axon occurs, microtubules are again critically involved in the rebuilding.

The microtubules have many different roles in forming and stabilizing synapses. A previous post showed the dynamic changes of dendrite spines and the different shapes. This occurs through microtubule actions. The growth into the spines is regulated by factors like BDNF. These microtubules bring material for the changing spine shapes with special motors.

https://jonlieffmd.com/blog/are-microtubules-the-brain-of-the-neuron