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    I'm a bit puzzled here.
    In some papers, I read that the ER stress is defined by the misfolding/unfolding of proteins in the ER. In other papers, I read that the misfolding/unfolding of proteins in the ER causes the ER stress. Others, I read this "Perturbations that disrupt ER homeostasis lead to the misfolding of proteins, ER stress..." and so on..
    So, I came up with the idea that the ER stress is any dysfunction or impairment of the ER caused by any kind of perturbation (stressor). But I'm unsure that this is true.. I could use some help in here :/

    thanks in advance!
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    After reading your post I think that you are talking about the ER with ribosomes where proteins are synthesised. In stress situations the ER (with the ribosomes) are responsing with misfoldings in protein synthesis by oppresing the translation processes. That is to say that amino acids which are creating to Proteins, are combined completely
    different than planned by the tranlsation porcess. So it comes to a wrong amino acid sequence and - consequently - to a wrong unfolded proteins (primary sturcture) which will be created to a wrong protein by folding (to a secondary structure first, after that to a tertiary and quatemary one). So an organism get proteins which are not needed.

    To sum up we can say that ER stress is another word for dysfunction of ER in stress situations.
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    (Original post by Kallisto)
    After reading your post I think that you are talking about the ER with ribosomes where proteins are synthesised. In stress situations the ER (with the ribosomes) are responsing with misfoldings in protein synthesis by oppresing the translation processes. That is to say that amino acids which are creating to Proteins, are combined completely
    different than planned by the tranlsation porcess. So it comes to a wrong amino acid sequence and - consequently - to a wrong unfolded proteins (primary sturcture) which will be created to a wrong protein by folding (to a secondary structure first, after that to a tertiary and quatemary one). So an organism get proteins which are not needed.

    To sum up we can say that ER stress is another word for dysfunction of ER in stress situations.
    Ok, and by stress situations you mean any kind of perturbation that affect the ER homeostasis, right?
    So, basically, you agree that ER stress is any dysfunction of the ER caused by any kind of perturbation (stressor), right?

    As we are referring to the ER with ribosomes, the main outcome of the ER dysfunction is the misfolding/unfolding of proteins and that usually represents the ER stress, but we cannot say that the ER stress is only the misfolding/unfolding of proteins, right? For example, if the ER stress persists, there is a release of Ca2+ from the ER. Is this another form of ER stress? Or is it a cause of the ER stress? Following your definition and mine, I'd say that it is another form of ER stress, is that wrong?
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    (Original post by miibay)
    Ok, and by stress situations you mean any kind of perturbation that affect the ER homeostasis, right?
    So, basically, you agree that ER stress is any dysfunction of the ER caused by any kind of perturbation (stressor), right? (...)
    Yes, I would say. The perpetuation comes into existence whenever the function of ribosomes is defected, or the homeostasis of it as you said. A bad example is a radioactive ray. Some radioactive rays (gamma ones) are so bad in their magnitude that the nucleotides, the basis pairs of any amino acids, are destroying in their combinations, what leads to a perpetuation of ribosomes automatically.

    (...)As we are referring to the ER with ribosomes, the main outcome of the ER dysfunction is the misfolding/unfolding of proteins and that usually represents the ER stress, but we cannot say that the ER stress is only the misfolding/unfolding of proteins, right? For example, if the ER stress persists, there is a release of Ca2+ from the ER. Is this another form of ER stress? Or is it a cause of the ER stress? Following your definition and mine, I'd say that it is another form of ER stress, is that wrong?
    After my personal understanding ER stress means the dealing of ER (respectively the ribosome) under stress situations in general. Under these circumstances it comes to misfoldings concerning the conditions automatically (see the example above). As far as I know the release of Ca2+ ions are responsible for signal transmissions in muscles and nerves (key word transmission of action potentials). In terms of neuroscience these ions are important in synapses to 'split' the synaptic vesicles, so (neuro-)transmitters are released, if I am not mistaken. Thus these transmitters are opened the neurotransmitter receptor, and so the action potential in every single muscle and nerve can be transmitted from Synapses to Synapses. So I would say ER stress works whenever ER does not release these Ca2+ ions to enable a transmission of an action potential. And yes, that would be an another form of ER stress, as it does not refer to proteins.
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    (Original post by Kallisto)
    Yes, I would say. The perpetuation comes into existence whenever the function of ribosomes is defected, or the homeostasis of it as you said. A bad example is a radioactive ray. Some radioactive rays (gamma ones) are so bad in their magnitude that the nucleotides, the basis pairs of any amino acids, are destroying in their combinations, what leads to a perpetuation of ribosomes automatically.



    After my personal understanding ER stress means the dealing of ER (respectively the ribosome) under stress situations in general. Under these circumstances it comes to misfoldings concerning the conditions automatically (see the example above). As far as I know the release of Ca2+ ions are responsible for signal transmissions in muscles and nerves (key word transmission of action potentials). In terms of neuroscience these ions are important in synapses to 'split' the synaptic vesicles, so (neuro-)transmitters are released, if I am not mistaken. Thus these transmitters are opened the neurotransmitter receptor, and so the action potential in every single muscle and nerve can be transmitted from Synapses to Synapses. So I would say ER stress works whenever ER does not release these Ca2+ ions to enable a transmission of an action potential. And yes, that would be an another form of ER stress, as it does not refer to proteins.
    Thanks!
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    (Original post by miibay)
    Thanks!
    You are welcome. Its good to know to help where someone can.
 
 
 
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