XVI International Symposium on Olfaction and Taste - ecro

<strong>XVI</strong> <strong>International</strong> <strong>Symposium</strong> on Olfaction and Taste
Poster session I Poster #159
An anatomical spotlight on the mouse vomeronasal organ
Tobias Ackels 1 , Daniela Fluegge 1 , Susanne Lipartowski 1 and Marc Spehr 1
1 RWTH Aachen University, Department of Chemosensation, Aachen, Germany
t.ackels@sensorik.rwth-aachen.de
As the peripheral sensory structure of the accessory olfactory system, the vomeronasal organ (VNO) predominantly
detects social chemosignals. Interaction with conspecifics, including social and sexual behavior, aggression and mate
choice are thus fundamental functions of the vomeronasal system. Therefore, the basic goal of this study is to provide a
multi-level structural perspective of the mouse VNO. Here, we take advantage of diverse tissue preparation methods in
combination with multiple microscopy and digital reconstruction techniques. From in vitro preparations of single
dissociated sensory neurons to acute in situ sections of the intact sensory epithelium, and from encapsulated VNO
dissections to whole-mount en-face preparations, our approach sheds light on the cell morphology and structural anatomy of
the VNO. Each preparation is suited for different electrophysiological and/or imaging techniques, thus, providing a
versatile experimental ‘toolkit’ for comprehensive physiological analyses of VNO function.
Poster session II Poster #160
The functional evolution of mammalian odorant receptor orthologs
Kaylin A Adipietro1 , Joel D Mainland1 1, 2
, Hiroaki Matsunami
1Duke University Medical Center, Molecular Genetics and Microbiology, Durham, NC, USA
2Duke University Medical Center, Neurobiology, Durham, NC, USA
kaa18@duke.edu
It is generally assumed that orthologs—genes related via speciation—retain equivalent function in closely related
species. However, this assumption remains largely untested. The mammalian odorant receptor (OR) repertoire is an
attractive model to study the functional evolution of orthologs because OR genes have been subjected to extensive gains
and losses between species, presumably caused by adaptation of the olfactory system to the environment. Yet, many ORs
have clear orthologs in closely related species. We investigated the functional properties of primate and rodent OR
orthologs expressed in heterologous cells to determine how well gene orthology predicts functional characteristics.
Using human and mouse ORs with previously identified ligands, we cloned 18 OR orthologs from chimpanzee and
rhesus macaque and 17 mouse-rat orthologous pairs that are broadly representative of the OR repertoire. We
functionally characterized the responses of OR orthologs to a wide panel of odors and found similar ligand
selectivity but differences in response magnitude. 87% of human-primate orthologs and 94% of mouse-rat orthologs
showed differences in receptor potency (EC50) and/or efficacy (dynamic range) to an individual ligand. Additionally,
we found that orthologs responded to a common ligand 82% of the time, while human receptors of the same
subfamily responded to the common ligand 41% of the time. Our results suggest that while OR orthologs tend to show
conserved ligand selectivity, their potency and/or efficacy dynamically change during evolution even in closely related
species. These functional changes in orthologs provide a platform for examining how the evolution of odorant receptors
can meet species-specific demands.
Poster session II Poster #168
Milk is time! Young mouse pups prefer milk odour from early rather than from late lactation
Syrina Al Aïn 1 , Laurine Belin 1 , Bruno Patris 1 and Benoist Schaal 1
1Center for Smell, Taste, and Food Science, Developmental Ethology and Cognitive Psychology Group, Dijon, FRANCE
syrina_al-ain@etu.u-bourgogne.fr
Milk is rich in odour-active compounds and mammalian newborns eagerly respond to its effluvium, especially when it
comes from conspecific females. In the mouse, milk is known to fluctuate compositionally during the first postpartum
days and then between weeks 1 and 2 of lactation, suggesting that its odorous profile may change accordingly. The
present study aims to assess whether there are periods in lactation during which milk would carry stronger olfactory
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