Article

Topographic organization of sensory projections to the olfactory bulb.

Department of Biochemistry and Molecular Biophysics, Columbia University College of Physicians and Surgeons, New York, New York 10032.
Cell (Impact Factor: 33.12). 01/1995; 79(6):981-91. DOI: 10.1016/0092-8674(94)90029-9
Source: PubMed

ABSTRACT The detection of odorant receptor mRNAs within the axon terminals of sensory neurons has permitted us to ask whether neurons expressing a given receptor project their axons to common glomeruli within the olfactory bulb. In situ hybridization with five different receptor probes demonstrates that axons from neurons expressing a given receptor converge on one, or at most, a few glomeruli within the olfactory bulb. Moreover, the position of specific glomeruli is bilaterally symmetric and is constant in different individuals within a species. These data support a model in which exposure to a given odorant may result in the stimulation of a spatially restricted set of glomeruli, such that the individual odorants would be associated with specific topographic patterns of activity within the olfactory bulb.

1 Bookmark
 · 
94 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: While the timing of neuronal activity in the olfactory bulb (OB) relative to sniffing has been the object of many studies, the behavioral relevance of timing information generated by patterned activation within the bulbar response has not been explored. Here we show, using sniff-triggered, dynamic, 2-D, optogenetic stimulation of mitral/tufted cells, that virtual odors that differ by as little as 13 ms are distinguishable by mice. Further, mice are capable of discriminating a virtual odor movie based on an optically imaged OB odor response versus the same virtual odor devoid of temporal dynamics-independently of the sniff-phase. Together with studies showing the behavioral relevance of graded glomerular responses and the response timing relative to odor sampling, these results imply that the mammalian olfactory system is capable of very high transient information transmission rates.
    PLoS Biology 12/2014; 12(12):e1002021. · 11.77 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To study olfaction, first we should know which physical or chemical properties of odorant molecules determine the response of olfactory receptor neurons, and then we should study the effect of those properties on the combinatorial encoding in olfactory system. In this work we show that the response of an olfactory receptor neuron in Drosophila depends on molecular volume of an odorant; The molecular volume determines the upper limits of the neural response, while the actual neural response may depend on other properties of the molecules. Each olfactory receptor prefers a particular volume, with some degree of flexibility. These two parameters predict the volume and flexibility of the binding-pocket of the olfactory receptors, which are the targets of structural biology studies. At the end we argue that the molecular volume can affects the quality of per-ceived smell of an odorant via the combinatorial encoding, molecular volume may mask other underlying relations between properties of molecules and neural re-sponses and we suggest a way to improve the selection of odorants in further ex-perimental studies.
    birxiv. 01/2015;
  • Flavour. 01/2014; 3(Suppl 1):P21.

Full-text (2 Sources)

Download
504 Downloads
Available from
Jun 1, 2014