Page 38 - ACHEMS 2012 PROGRAM

#P29 POSTER SESSION I:
MULTIMODAL RECEPTION;
CHEMOSENSATION & DISEASE;
TASTE PERIPHERY; OLFACTION PERIPHERY
MUPP1 is a General Organizer for Olfactory Signaling
Sabrina Baumgart1, Fabian Jansen1, Ruth Dooley2, Marc Spehr3,
Hanns Hatt1, Eva M Neuhaus4
1Ruhr-University Bochum Bochum, Germany, 2Beaumont Hospital
Dublin, Ireland, 3RWTH-Aachen University Aachen, Germany,
4NeuroScience Research Center Charité Berlin, Germany
Olfactory signaling is dependent on various proteins and fine-tuned
through different processes. These individual signaling steps have
to be organized in the densely packed neuron in a spatiotemporal
manner. Most of the essential components of this pathway are
already known but the question arises how those get orchestrated.
In the present study, we identified the PDZ protein MUPP1 as the
first potential scaffolding candidate for olfactory signaling. We
were able to demonstrate various MUPP1-OR interactions, using a
large-scale peptide microarray approach with the 13 individual
PDZ domains of MUPP1 and murine olfactory receptors of every
subfamily. Moreover, co-immunoprecipitations of MUPP1 and
important olfactory signaling proteins validated the existence of an
olfactory PDZome. To functionally characterize the PDZ-
dependency of olfactory signaling in olfactory neurons, we
established patch clamping of olfactory sensory neurons in acute
slices of transgenic mOR-EG mice and designed an inhibitory
peptide, specific for PDZ proteins. Remarkably, odor-evoked
current amplitudes were strongly reduced and adaptation was
impaired after uncoupling the PDZ-OR interaction. In conclusion,
we confirmed the presence of a MUPP1-mediated olfactory
signalosome in olfactory sensory neurons and showed that accurate
olfactory signaling is a PDZ-dependent mechanism.
#P30 POSTER SESSION I:
MULTIMODAL RECEPTION;
CHEMOSENSATION & DISEASE;
TASTE PERIPHERY; OLFACTION PERIPHERY
Combinatorial and modular encoding of the mouse olfactory
signatures by major urinary proteins (MUPs): an overview
of the past two decades
Gennady A. Churakov1, Anatoly A. Philimonenko2,
Elena M. Fedorova3, Irina I. Ermakova3, Sergey N. Novikov3
1Institute of Experimental Pathology/Molecular Neurobiology
(ZMBE), University of Muenster Muenster, Germany,
2Institute of Molecular Genetics, v.v.i., Academy of Sciences
of the Czech Republic Prague, Czech Republic,
3I.P. Pavlov Institute of Physiology, Russian Academy of
Sciences Saint Petersburg, Russia
The first evidence that the activity of androgen-dependent
pheromones in mice may be strongly associated with main urinary
protein fraction (major urinary proteins, MUPs) was presented at
14th AChemS meeting two decades ago (Churakov et al., 1992).
Coupled with further data on differential capacities of various
MUPs to bind several physiologically active ligands (Bacchini et
al., 1992; Böcskei et al., 1992), these studies opened practically
unexplored avenue of MUPs’ significance in the neurobiology of
olfaction in Mus musculus . In this report we present results of our
recent and ongoing studies on MUPs significance in encoding
olfactory signatures (images) in laboratory mice of genealogically
unrelated strains (CBA/LacY and C57BL/6JY) and their reciprocal
F1 hybrids. Quantitative evaluation of MUP fractions with different
electrophoretic mobility reveals that strain-specific combination
and proportion of individual fractions can encode age, sex,
physiological state, and genotype of the mouse. The genotype-
specific adult MUP combinatorial profile consists of two distinct
protein subsets (modules), which appear in both sexes very soon
after weaning and resemble a “bar-code”. Taking into account that
MUPs without native ligands can efficiently activate vomeronasal
neurons (Chamero et al., 2007; 2011) and that the expression
patterns of pheromone receptors (V2Rs) are also combinatorial
(Silvotti et al., 2007) and partially sex-specific (He et al., 2008;
2010), our data provide valuable insights into fine molecular
mechanisms of decoding unique pheromone blends, based on an
intriguing MUPs↔V2Rs complementary protein interplay.
Coupled with other data on modular organization of the olfactory
decoding our studies proposed that the recognition of MUP’
functional modules is also based on modular principles.
Acknowledgements: Supported by Russian Foundation for Basic
Research (projects 02-04-49273, 04-04-63050, 07-04-01762)
and Russian State Science and Technology Program “Priority
Frontiers in Genetics” (project 2.152).
#P31 POSTER SESSION I:
MULTIMODAL RECEPTION;
CHEMOSENSATION & DISEASE;
TASTE PERIPHERY; OLFACTION PERIPHERY
Unraveling the Mechanism Behind Scent-Marking in
Male Mice
Angeldeep Kaur, Lisa Stowers
The Scripps Research Institute La Jolla, CA, USA
Previous work has shown urine to be a rich source of chemical
information, carrying odor cues as well as pheromonal information.
Urinary marks can signal the gender, sexual maturity and social
status of the depositing animal. Mice have the ability to distinguish
their own urinary deposits from that of another conspecific.
However, the precise mechanism by which individual recognition
is accomplished is yet to be elucidated. The objective of this project
is to gain insight into the mechanisms underlying individual
recognition in male mice as manifested by their countermarking
behavior. Biochemically fractionated urine and recombinantly
expressed major urinary proteins were tested in a countermarking
behavioral assay to uncover the mechanism by which urinary
signals are used to distinguish the identity of the depositing animal.
It was found that, as previously suggested, the protein containing
high molecular weight fraction of non-self adult male urine was
necessary and sufficient to promote countermarking behavior in
BALBcByJ male mice. Recombinantly expressed individual
proteins were sufficient to produce the behavior. Experiments are
underway to further characterize how self and non-self urine
signatures are differentially perceived. Investigation of these hard-
wired circuits will allow for a greater understanding of how neural
coding is employed to translate chemical informationinto action.
38 | AChemS Abstracts 2012 Abstracts are printed as submitted by the author(s)
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