Comments on: Neurons mature rapidly at birth http://www.futurity.org/health-medicine/neurons-mature-rapidly-at-birth/ Research news from leading universities Sun, 12 Feb 2012 00:52:25 +0000 hourly 1 http://wordpress.org/?v=3.0.4 By: Roy Niles http://www.futurity.org/health-medicine/neurons-mature-rapidly-at-birth/comment-page-1/#comment-2953 Roy Niles Fri, 04 Dec 2009 22:26:40 +0000 http://futurity.org/?p=6205#comment-2953 Wolfgang, thanks for the response! I used the term "engineering function" as a reference to the distinct possibility that life forms evolve at least in part through their own "trial and error" problem solving efforts. It seemed that this could then be an example of how biological nervous systems have taken advantage of their "experiences" over the ages to engineer themselves accordingly. Involving themselves in the "natural selection" process rather than having been somehow separate from that process. Wolfgang, thanks for the response!
I used the term “engineering function” as a reference to the distinct possibility that life forms evolve at least in part through their own “trial and error” problem solving efforts. It seemed that this could then be an example of how biological nervous systems have taken advantage of their “experiences” over the ages to engineer themselves accordingly. Involving themselves in the “natural selection” process rather than having been somehow separate from that process.

]]> By: Wolfgang Liedtke http://www.futurity.org/health-medicine/neurons-mature-rapidly-at-birth/comment-page-1/#comment-2948 Wolfgang Liedtke Fri, 04 Dec 2009 21:32:36 +0000 http://futurity.org/?p=6205#comment-2948 Roy, thank you very much. This mechanism happens very early in ontogeny, in rodents immediately after birth, and in humans even in the last trimester. Yet, we have included one particular experiment into our publication that answers your question in the affirmative, namely the stimulation with brain-derived neurotrophic factor. Exposure to BDNF accelerates the chloride switch, and this mechanism is fully dependent on the "dual-RE-1" DNA binding site in the Kcc2 gene that we have discovered. In this experiment, BDNF is a surrogate for experience. Another example comes from one of the referenced papers by Ganguly from Mooming Poo's group. They used low-level potassium chloride exposure (10mM KCl), and it accelerated the chloride shift as well. 10 mM KCl mildly depolarizes the nerve cell, thus, this is another surrogate for "experience", namely chronic mild depolarization, i.e. neural activity. However, I am a bit lost at your use of the term "engineering function". Finally, did this contribute to CNS evolution ? - Supposedly it did, where analysis of the pufferfish, a "lower" vertebrate, is particularly revealing. Of the dual-RE-1 DNA binding site, the more distal one is very well conserved whereas the up-stream one is not. Thus, the novel up-stream RE-1 site evolved later. Wolfgang Roy,

thank you very much.

This mechanism happens very early in ontogeny, in rodents immediately after birth, and in humans even in the last trimester. Yet, we have included one particular experiment into our publication that answers your question in the affirmative, namely the stimulation with brain-derived neurotrophic factor. Exposure to BDNF accelerates the chloride switch, and this mechanism is fully dependent on the “dual-RE-1″ DNA binding site in the Kcc2 gene that we have discovered. In this experiment, BDNF is a surrogate for experience. Another example comes from one of the referenced papers by Ganguly from Mooming Poo’s group. They used low-level potassium chloride exposure (10mM KCl), and it accelerated the chloride shift as well. 10 mM KCl mildly depolarizes the nerve cell, thus, this is another surrogate for “experience”, namely chronic mild depolarization, i.e. neural activity.

However, I am a bit lost at your use of the term “engineering function”.

Finally, did this contribute to CNS evolution ? – Supposedly it did, where analysis of the pufferfish, a “lower” vertebrate, is particularly revealing. Of the dual-RE-1 DNA binding site, the more distal one is very well conserved whereas the up-stream one is not. Thus, the novel up-stream RE-1 site evolved later.

Wolfgang

]]> By: Roy Niles http://www.futurity.org/health-medicine/neurons-mature-rapidly-at-birth/comment-page-1/#comment-2815 Roy Niles Wed, 02 Dec 2009 21:53:38 +0000 http://futurity.org/?p=6205#comment-2815 So is this also an engineering function that "learns" from experience and has contributed to the evolution of the brain accordingly? So is this also an engineering function that “learns” from experience and has contributed to the evolution of the brain accordingly?

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