GSBS Student Publications

Title

Learned odor discrimination in Drosophila without combinatorial odor maps in the antennal lobe

Student Author(s)

Shamik DasGupta

GSBS Program

Neuroscience

UMMS Affiliation

Department of Neurobiology; Waddell Lab; Graduate School of Biomedical Sciences, Neuroscience Program

Date

11-11-2008

Document Type

Article

Medical Subject Headings

Animals; Brain; Discrimination Learning; Drosophila; Drosophila Proteins; Olfactory Perception; Olfactory Receptor Neurons; Receptors, Odorant

Disciplines

Behavioral Neurobiology

Abstract

A unifying feature of mammalian and insect olfactory systems is that olfactory sensory neurons (OSNs) expressing the same unique odorant-receptor gene converge onto the same glomeruli in the brain [1-7]. Most odorants activate a combination of receptors and thus distinct patterns of glomeruli, forming a proposed combinatorial spatial code that could support discrimination between a large number of odorants [8-11]. OSNs also exhibit odor-evoked responses with complex temporal dynamics [11], but the contribution of this activity to behavioral odor discrimination has received little attention [12]. Here, we investigated the importance of spatial encoding in the relatively simple Drosophila antennal lobe. We show that Drosophila can learn to discriminate between two odorants with one functional class of Or83b-expressing OSNs. Furthermore, these flies encode one odorant from a mixture and cross-adapt to odorants that activate the relevant OSN class, demonstrating that they discriminate odorants by using the same OSNs. Lastly, flies with a single class of Or83b-expressing OSNs recognize a specific odorant across a range of concentration, indicating that they encode odorant identity. Therefore, flies can distinguish odorants without discrete spatial codes in the antennal lobe, implying an important role for odorant-evoked temporal dynamics in behavioral odorant discrimination.

Rights and Permissions

Citation: Curr Biol. 2008 Nov 11;18(21):1668-74. Epub 2008 Oct 23. Link to article on publisher's site

DOI of Published Version

10.1016/j.cub.2008.08.071

Related Resources

Link to Article in PubMed

Journal Title

Current biology : CB

PubMed ID

18951022