Stimulating Theories in Molecular Neuroscience

| | Program | | Abstracts | | References | | Further information | | Flyer | |

The following half-day meeting, organized by the Biological Computation group and hosted by the Newton Institute will take place on November 7th 1997.

All are welcome to attend.


Program


2.00 Do we smell molecular vibrations?
L. Turin
Department of Anatomy and Developmental Biology, UCL.
3.30 Tea.
4.00 D-amino acids and the role of glia in brain function.
M. Schell
Department of Pharmacology, University of Cambridge.
5.30 Drinks and light refreshments.

Talks will be about 50 minutes long and there will be ample time for discussion.


Abstracts

Do we smell molecular vibrations?

L. Turin will discuss a novel theory of primary olfaction. It is proposed that olfactory receptors respond not to the shape of the molecules but to their vibrations. A detailed and plausible mechanism --- inelastic electron tunnelling --- is provided for transduction of molecular vibrations. Several examples can be given of correlations between tunnelling spectrum and odour in structurally unrelated molecules. It is thus suggested that olfaction, like colour vision and hearing, is a spectral sense.

D-Amino Acids and the role of glia in brain function.

The surprising discovery of substantial quantities of free D-serine in brain suggests that the "wrong isomer" of an amino acid could be an important neuromodulator in the telencephalon, the part of the brain enlarged in mammals. The receptor for D-serine is the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor. This receptor is implicated in most forms of memory formation in brain, and is distinct from other excitatory receptors in that it requires the simultaneous occupation of two independent ligand binding sites to gate its calcium channel. D-Serine acts at the "glycine site," which is distinct from the site where glutamate binds. Brain mapping studies, using stereoselective antibodies to D-serine, reveal that the amino acid is present exclusively in a population of gray matter glial cells, in close vicinity to NMDA receptors. D-Serine is concentrated in the cytosol of these astrocytes, which are often also found near blood vessels. It is made by the direct enzymatic racemezation of L-serine in these cells. Since almost all cytosolic L-serine comes from glucose, the levels of D-serine might be controlled by neuronal energy demand, through metabolic compartmentalization and coupling in gray matter.

The excitable nature of neurons has led to the neural doctrine, in which neurons are the primary information processing cells in the brain. However, recent observations, such as the waves of calcium that pass through glial networks in response to neurotransmitters, suggest that glia influence brain activity and plasticity. Behavior may be a combined function of neuronal and glial connectivity and chatter, working on different time scales and distances. Substantial phylogenetic evidence exists suggesting that both glia in general and D-serine specifically have important computational functions in big-brained mammals, and I will attempt to define some of the computationally relevant questions about neuron/glia interaction.


References

@Article{turin96,
  author = 	 "L. Turin",
  title = 	 "A Spectroscopic Mechanism for Primary Olfactory Reception",
  journal =	 "Chem. Senses",
  year =	 1996,
  volume =	 21,
  number =	 "773-791"
}

@article{Schell97,
  title={D-Serine as a Neuromodulator: Regional and developmental 
          Localizations in Rat Brain Glia Resemble {NMDA} Receptors},
  author={Schell, M. J., Brady, R. O., Molliver, M. E., Snyder, S. H.},
  journal={Journal of Neuroscience},
 year={1997},
 volume={17},
 number={5},
 pages={1604-1615}
}

Further information

Venue: Newton Institute. Clarkson Road, Cambridge.

Registration: the meeting is open to all.
If you would like to join the speakers for dinner after the meeting please contact David MacKay by email.


David MacKay <mackay@mrao.cam.ac.uk>
Last modified: Thu Oct 2 13:59:50 1997