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Cohen O, Kahan A, Steinberg I, Malinowski ST, Rokni D, Spehr M, Ben-Shaul Y. Stimulus-Induced Theta-Band LFP Oscillations Format Neuronal Representations of Social Chemosignals in the Mouse Accessory Olfactory Bulb. J Neurosci 2023; 43:8700-8722. [PMID: 37903594 PMCID: PMC10727196 DOI: 10.1523/jneurosci.1055-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 10/13/2023] [Accepted: 10/16/2023] [Indexed: 11/01/2023] Open
Abstract
Social communication is crucial for the survival of many species. In most vertebrates, a dedicated chemosensory system, the vomeronasal system (VNS), evolved to process ethologically relevant chemosensory cues. The first central processing stage of the VNS is the accessory olfactory bulb (AOB), which sends information to downstream brain regions via AOB mitral cells (AMCs). Recent studies provided important insights about the functional properties of AMCs, but little is known about the principles that govern their coordinated activity. Here, we recorded local field potentials (LFPs) and single-unit activity in the AOB of adult male and female mice during presentation of natural stimuli. Our recordings reveal prominent LFP theta-band oscillatory episodes with a characteristic spatial pattern across the AOB. Throughout an experiment, the AOB network shows varying degrees of similarity to this pattern, in a manner that depends on the sensory stimulus. Analysis of LFP signal polarity and single-unit activity indicates that oscillatory episodes are generated locally within the AOB, likely representing a reciprocal interaction between AMCs and granule cells. Notably, spike times of many AMCs are constrained to the negative LFP oscillation phase in a manner that can drastically affect integration by downstream processing stages. Based on these observations, we propose that LFP oscillations may gate, bind, and organize outgoing signals from individual AOB neurons to downstream processing stages. Our findings suggest that, as in other neuronal systems and brain regions, population-level oscillations play a key role in organizing and enhancing transmission of socially relevant chemosensory information.SIGNIFICANCE STATEMENT The accessory olfactory bulb (AOB) is the first central stage of the vomeronasal system, a chemosensory system dedicated to processing cues from other organisms. Information from the AOB is conveyed to other brain regions via activity of its principal neurons, AOB mitral cells (AMCs). Here, we show that socially relevant sensory stimulation of the mouse vomeronasal system leads not only to changes in AMC activity, but also to distinct theta-band (∼5 Hz) oscillatory episodes in the local field potential. Notably AMCs favor the negative phase of these oscillatory events. Our findings suggest a novel mechanism for the temporal coordination of distributed patterns of neuronal activity, which can serve to efficiently activate downstream processing stages.
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Affiliation(s)
- Oksana Cohen
- Department of Medical Neurobiology, Institute for Medical Research Israel Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Anat Kahan
- Department of Medical Neurobiology, Institute for Medical Research Israel Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
- Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University, Rehovot 7610001, Israel
| | - Idan Steinberg
- Alpha Program, Future Scientist Center, The Hebrew University Youth Division, Jerusalem 9190401, Israel
| | - Sebastian T Malinowski
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, 52062 Aachen, Germany
| | - Dan Rokni
- Department of Medical Neurobiology, Institute for Medical Research Israel Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, 52062 Aachen, Germany
| | - Yoram Ben-Shaul
- Department of Medical Neurobiology, Institute for Medical Research Israel Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
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2
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Yoles-Frenkel M, Shea SD, Davison IG, Ben-Shaul Y. The Bruce effect: Representational stability and memory formation in the accessory olfactory bulb of the female mouse. Cell Rep 2022; 40:111262. [PMID: 36001975 PMCID: PMC9446479 DOI: 10.1016/j.celrep.2022.111262] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 06/12/2022] [Accepted: 08/04/2022] [Indexed: 11/26/2022] Open
Abstract
In the Bruce effect, a mated female mouse becomes resistant to the pregnancy-blocking effect of the stud. Various lines of evidence suggest that this form of behavioral imprinting results from reduced sensitivity of the female's accessory olfactory bulb (AOB) to the stud's chemosignals. However, the AOB's combinatorial code implies that diminishing responses to one individual will distort representations of other stimuli. Here, we record extracellular responses of AOB neurons in mated and unmated female mice while presenting urine stimuli from the stud and from other sources. We find that, while initial sensory responses in the AOB (within a timescale required to guide social interactions) remain stable, responses to extended stimulation (as required for eliciting the pregnancy block) display selective attenuation of stud-responsive neurons. Such temporal disassociation could allow attenuation of slow-acting endocrine processes in a stimulus-specific manner without compromising ongoing representations that guide behavior.
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Affiliation(s)
- Michal Yoles-Frenkel
- Department of Medical Neurobiology, Hebrew University Medical School, Faculty of Medicine, Institute for Medical Research Israel Canada, the Hebrew University, Jerusalem 91120, Israel
| | - Stephen D Shea
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Ian G Davison
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Yoram Ben-Shaul
- Department of Medical Neurobiology, Hebrew University Medical School, Faculty of Medicine, Institute for Medical Research Israel Canada, the Hebrew University, Jerusalem 91120, Israel.
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3
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Bansal R, Nagel M, Stopkova R, Sofer Y, Kimchi T, Stopka P, Spehr M, Ben-Shaul Y. Do all mice smell the same? Chemosensory cues from inbred and wild mouse strains elicit stereotypic sensory representations in the accessory olfactory bulb. BMC Biol 2021; 19:133. [PMID: 34182994 PMCID: PMC8240315 DOI: 10.1186/s12915-021-01064-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 06/06/2021] [Indexed: 11/10/2022] Open
Abstract
Background For many animals, chemosensory cues are vital for social and defensive interactions and are primarily detected and processed by the vomeronasal system (VNS). These cues are often inherently associated with ethological meaning, leading to stereotyped behaviors. Thus, one would expect consistent representation of these stimuli across different individuals. However, individuals may express different arrays of vomeronasal sensory receptors and may vary in the pattern of connections between those receptors and projection neurons in the accessory olfactory bulb (AOB). In the first part of this study, we address the ability of individuals to form consistent representations despite these potential sources of variability. The second part of our study is motivated by the fact that the majority of research on VNS physiology involves the use of stimuli derived from inbred animals. Yet, it is unclear whether neuronal representations of inbred-derived stimuli are similar to those of more ethologically relevant wild-derived stimuli. Results First, we compared sensory representations to inbred, wild-derived, and wild urine stimuli in the AOBs of males from two distinct inbred strains, using them as proxies for individuals. We found a remarkable similarity in stimulus representations across the two strains. Next, we compared AOB neuronal responses to inbred, wild-derived, and wild stimuli, again using male inbred mice as subjects. Employing various measures of neuronal activity, we show that wild-derived and wild stimuli elicit responses that are broadly similar to those from inbred stimuli: they are not considerably stronger or weaker, they show similar levels of sexual dimorphism, and when examining population-level activity, cluster with inbred mouse stimuli. Conclusions Despite strain-specific differences and apparently random connectivity, the AOB can maintain stereotypic sensory representations for broad stimulus categories, providing a substrate for common stereotypical behaviors. In addition, despite many generations of inbreeding, AOB representations capture the key ethological features (i.e., species and sex) of wild-derived and wild counterparts. Beyond these broad similarities, representations of stimuli from wild mice are nevertheless distinct from those elicited by inbred mouse stimuli, suggesting that laboratory inbreeding has indeed resulted in marked modifications of urinary secretions. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01064-7.
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Affiliation(s)
- Rohini Bansal
- Department of Medical Neurobiology, Institute for Medical Research Israel Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Maximilian Nagel
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Romana Stopkova
- BIOCEV group, Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Yizhak Sofer
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Tali Kimchi
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Pavel Stopka
- BIOCEV group, Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Yoram Ben-Shaul
- Department of Medical Neurobiology, Institute for Medical Research Israel Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
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Competitive binding predicts nonlinear responses of olfactory receptors to complex mixtures. Proc Natl Acad Sci U S A 2019; 116:9598-9603. [PMID: 31000595 PMCID: PMC6511041 DOI: 10.1073/pnas.1813230116] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In color vision, the quantitative rules for mixing lights to make a target color are well understood. By contrast, the rules for mixing odorants to make a target odor remain elusive. A solution to this problem in vision relied on characterizing receptor responses to different wavelengths of light and subsequently relating these responses to perception. In olfaction, experimentally measuring receptor responses to a representative set of complex mixtures is intractable due to the vast number of possibilities. To meet this challenge, we develop a biophysical model that predicts mammalian receptor responses to complex mixtures using responses to single odorants. The dominant nonlinearity in our model is competitive binding (CB): Only one odorant molecule can attach to a receptor binding site at a time. This simple framework predicts receptor responses to mixtures of up to 12 monomolecular odorants to within 15% of experimental observations and provides a powerful method for leveraging limited experimental data. Simple extensions of our model describe phenomena such as synergy, overshadowing, and inhibition. We demonstrate that the presence of such interactions can be identified via systematic deviations from the competitive-binding model.
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5
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Chan HK, Hersperger F, Marachlian E, Smith BH, Locatelli F, Szyszka P, Nowotny T. Odorant mixtures elicit less variable and faster responses than pure odorants. PLoS Comput Biol 2018; 14:e1006536. [PMID: 30532147 PMCID: PMC6287832 DOI: 10.1371/journal.pcbi.1006536] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/29/2018] [Indexed: 11/18/2022] Open
Abstract
In natural environments, odors are typically mixtures of several different chemical compounds. However, the implications of mixtures for odor processing have not been fully investigated. We have extended a standard olfactory receptor model to mixtures and found through its mathematical analysis that odorant-evoked activity patterns are more stable across concentrations and first-spike latencies of receptor neurons are shorter for mixtures than for pure odorants. Shorter first-spike latencies arise from the nonlinear dependence of binding rate on odorant concentration, commonly described by the Hill coefficient, while the more stable activity patterns result from the competition between different ligands for receptor sites. These results are consistent with observations from numerical simulations and physiological recordings in the olfactory system of insects. Our results suggest that mixtures allow faster and more reliable olfactory coding, which could be one of the reasons why animals often use mixtures in chemical signaling.
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Affiliation(s)
- Ho Ka Chan
- Sussex Neuroscience, School of Engineering and Informatics, University of Sussex, Falmer, Brighton, United Kingdom
| | - Fabian Hersperger
- Department of Neuroscience, University of Konstanz, Konstanz, Germany
| | - Emiliano Marachlian
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET) and Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
| | - Brian H. Smith
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Fernando Locatelli
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET) and Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
| | - Paul Szyszka
- Department of Neuroscience, University of Konstanz, Konstanz, Germany
| | - Thomas Nowotny
- Sussex Neuroscience, School of Engineering and Informatics, University of Sussex, Falmer, Brighton, United Kingdom
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6
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Temporal Response Properties of Accessory Olfactory Bulb Neurons: Limitations and Opportunities for Decoding. J Neurosci 2018; 38:4957-4976. [PMID: 29712784 DOI: 10.1523/jneurosci.2091-17.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 02/27/2018] [Accepted: 04/22/2018] [Indexed: 01/09/2023] Open
Abstract
The vomeronasal system (VNS) is a major vertebrate chemosensory system that functions in parallel to the main olfactory system (MOS). Despite many similarities, the two systems dramatically differ in the temporal domain. While MOS responses are governed by breathing and follow a subsecond temporal scale, VNS responses are uncoupled from breathing and evolve over seconds. This suggests that the contribution of response dynamics to stimulus information will differ between these systems. While temporal dynamics in the MOS are widely investigated, similar analyses in the accessory olfactory bulb (AOB) are lacking. Here, we have addressed this issue using controlled stimulus delivery to the vomeronasal organ of male and female mice. We first analyzed the temporal properties of AOB projection neurons and demonstrated that neurons display prolonged, variable, and neuron-specific characteristics. We then analyzed various decoding schemes using AOB population responses. We showed that compared with the simplest scheme (i.e., integration of spike counts over the entire response period), the division of this period into smaller temporal bins actually yields poorer decoding accuracy. However, optimal classification accuracy can be achieved well before the end of the response period by integrating spike counts within temporally defined windows. Since VNS stimulus uptake is variable, we analyzed decoding using limited information about stimulus uptake time, and showed that with enough neurons, such time-invariant decoding is feasible. Finally, we conducted simulations that demonstrated that, unlike the main olfactory bulb, the temporal features of AOB neurons disfavor decoding with high temporal accuracy, and, rather, support decoding without precise knowledge of stimulus uptake time.SIGNIFICANCE STATEMENT A key goal in sensory system research is to identify which metrics of neuronal activity are relevant for decoding stimulus features. Here, we describe the first systematic analysis of temporal coding in the vomeronasal system (VNS), a chemosensory system devoted to socially relevant cues. Compared with the main olfactory system, timescales of VNS function are inherently slower and variable. Using various analyses of real and simulated data, we show that the consideration of response times relative to stimulus uptake can aid the decoding of stimulus information from neuronal activity. However, response properties of accessory olfactory bulb neurons favor decoding schemes that do not rely on the precise timing of stimulus uptake. Such schemes are consistent with the variable nature of VNS stimulus uptake.
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7
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Hsiang JC, Johnson KP, Madisen L, Zeng H, Kerschensteiner D. Local processing in neurites of VGluT3-expressing amacrine cells differentially organizes visual information. eLife 2017; 6:31307. [PMID: 29022876 PMCID: PMC5653236 DOI: 10.7554/elife.31307] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/11/2017] [Indexed: 12/17/2022] Open
Abstract
Neurons receive synaptic inputs on extensive neurite arbors. How information is organized across arbors and how local processing in neurites contributes to circuit function is mostly unknown. Here, we used two-photon Ca2+ imaging to study visual processing in VGluT3-expressing amacrine cells (VG3-ACs) in the mouse retina. Contrast preferences (ON vs. OFF) varied across VG3-AC arbors depending on the laminar position of neurites, with ON responses preferring larger stimuli than OFF responses. Although arbors of neighboring cells overlap extensively, imaging population activity revealed continuous topographic maps of visual space in the VG3-AC plexus. All VG3-AC neurites responded strongly to object motion, but remained silent during global image motion. Thus, VG3-AC arbors limit vertical and lateral integration of contrast and location information, respectively. We propose that this local processing enables the dense VG3-AC plexus to contribute precise object motion signals to diverse targets without distorting target-specific contrast preferences and spatial receptive fields.
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Affiliation(s)
- Jen-Chun Hsiang
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.,Graduate Program in Neuroscience, Washington University School of Medicine, Saint Louis, United States
| | - Keith P Johnson
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.,Graduate Program in Neuroscience, Washington University School of Medicine, Saint Louis, United States
| | - Linda Madisen
- Allen Institute for Brain Science, Seattle, United States
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, United States
| | - Daniel Kerschensteiner
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.,Department of Neuroscience, Washington University School of Medicine, Saint Louis, United States.,Department of Biomedical Engineering, Washington University School of Medicine, Saint Louis, United States.,Hope Center for Neurological Disorders, Washington University School of Medicine, Saint Louis, United States
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8
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Aprison EZ, Ruvinsky I. Counteracting Ascarosides Act through Distinct Neurons to Determine the Sexual Identity of C. elegans Pheromones. Curr Biol 2017; 27:2589-2599.e3. [DOI: 10.1016/j.cub.2017.07.034] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/26/2017] [Accepted: 07/13/2017] [Indexed: 01/12/2023]
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9
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Abstract
Social interactions are often powerful drivers of learning. In female mice, mating creates a long-lasting sensory memory for the pheromones of the stud male that alters neuroendocrine responses to his chemosignals for many weeks. The cellular and synaptic correlates of pheromonal learning, however, remain unclear. We examined local circuit changes in the accessory olfactory bulb (AOB) using targeted ex vivo recordings of mating-activated neurons tagged with a fluorescent reporter. Imprinting led to striking plasticity in the intrinsic membrane excitability of projection neurons (mitral cells, MCs) that dramatically curtailed their responsiveness, suggesting a novel cellular substrate for pheromonal learning. Plasticity was selectively expressed in the MC ensembles activated by the stud male, consistent with formation of memories for specific individuals. Finally, MC excitability gained atypical activity-dependence whose slow dynamics strongly attenuated firing on timescales of several minutes. This unusual form of AOB plasticity may act to filter sustained or repetitive sensory signals. DOI:http://dx.doi.org/10.7554/eLife.25421.001 To navigate social situations, humans and other animals need to remember who they have interacted with and how it went, and adjust their behavior in future encounters accordingly. For example, your physical actions, and even your body’s physiological responses, will be very different when you encounter the last person you kissed instead of the last person you fought with (assuming this is not the same person!). Memories of social interactions can have dramatic consequences. For instance, male mice often kill the offspring of other males. Female mice appear to have adopted a countermeasure to avoid losing a litter of pups to such aggression: they will spontaneously abort a pregnancy when exposed to chemicals called pheromones from unfamiliar males. However, when the female mouse is exposed to the pheromones of the male she mated with she maintains her pregnancy. Exactly how the memories of previous social interactions with the males affect the female’s pheromone responses is not fully understood. To investigate how the female is able to respond differently to different males, Gao et al. recorded the activity of individual neurons taken from the brain tissue of female mice who had recently mated. The recordings showed that previous social experiences produce learning-related changes in the brain of the female mouse that reduce how sensitively pheromone-detecting neurons respond to the chemical cues of the male mate. This suppresses the signals that the neurons would otherwise send to trigger an abortion in response to male pheromones. Gao et al. also used fluorescent tags to identify which neurons in the female’s brain had been activated during mating. This revealed that only those neurons that had been activated by the mate become unresponsive when the cells again encountered his pheromones. This suggests that a set of neurons in the female’s brain records the chemical ‘fingerprint’ of the mate, and can then selectively filter out that mate’s pheromone signals. Many other social interactions, such as parenting, are also strongly shaped by experience. The results presented by Gao et al. may therefore offer wider lessons for understanding how the brain targets different behaviors toward specific individuals. It will also be important to investigate how highly arousing experiences cause such powerful memories to form. This could ultimately help us to better understand – and potentially treat – conditions like post-traumatic stress disorder. DOI:http://dx.doi.org/10.7554/eLife.25421.002
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Affiliation(s)
- Yuan Gao
- Department of Biology, Boston University, Boston, United States
| | - Carl Budlong
- Department of Biology, Boston University, Boston, United States
| | - Emily Durlacher
- Program in Neuroscience and Behavior, Mount Holyoke College, South Hadley, United States
| | - Ian G Davison
- Department of Biology, Boston University, Boston, United States
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10
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Doyle WI, Dinser JA, Cansler HL, Zhang X, Dinh DD, Browder NS, Riddington IM, Meeks JP. Faecal bile acids are natural ligands of the mouse accessory olfactory system. Nat Commun 2016; 7:11936. [PMID: 27324439 PMCID: PMC4919516 DOI: 10.1038/ncomms11936] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 05/13/2016] [Indexed: 01/06/2023] Open
Abstract
The accessory olfactory system (AOS) guides behaviours that are important for survival and reproduction, but understanding of AOS function is limited by a lack of identified natural ligands. Here we report that mouse faeces are a robust source of AOS chemosignals and identify bile acids as a class of natural AOS ligands. Single-unit electrophysiological recordings from accessory olfactory bulb neurons in ex vivo preparations show that AOS neurons are strongly and selectively activated by peripheral stimulation with mouse faecal extracts. Faecal extracts contain several unconjugated bile acids that cause concentration-dependent neuronal activity in the AOS. Many AOS neurons respond selectively to bile acids that are variably excreted in male and female mouse faeces, and others respond to bile acids absent in mouse faeces. These results identify faeces as a natural source of AOS information, and suggest that bile acids may be mammalian pheromones and kairomones. The accessory olfactory system (AOS) processes social chemosensory information and guides behaviors that are important for survival and reproduction in mammals. Here the authors report that mouse feces are a source of AOS neuronal activity and identify unconjugated bile acids in feces as a class of natural AOS ligands.
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Affiliation(s)
- Wayne I Doyle
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.,Neuroscience Graduate Program, The University of Texas, Southwestern Graduate School of Biomedical Sciences, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Jordan A Dinser
- Department of Chemistry, The University of Texas, 120 Inner Campus Drive, Austin, Texas 78712, USA
| | - Hillary L Cansler
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.,Neuroscience Graduate Program, The University of Texas, Southwestern Graduate School of Biomedical Sciences, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Xingjian Zhang
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.,Neuroscience Graduate Program, The University of Texas, Southwestern Graduate School of Biomedical Sciences, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Daniel D Dinh
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Natasha S Browder
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Ian M Riddington
- Department of Chemistry, The University of Texas, 120 Inner Campus Drive, Austin, Texas 78712, USA
| | - Julian P Meeks
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
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11
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Ben-Shaul Y. Extracting Social Information from Chemosensory Cues: Consideration of Several Scenarios and Their Functional Implications. Front Neurosci 2015; 9:439. [PMID: 26635515 PMCID: PMC4653286 DOI: 10.3389/fnins.2015.00439] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/30/2015] [Indexed: 11/16/2022] Open
Abstract
Across all sensory modalities, stimuli can vary along multiple dimensions. Efficient extraction of information requires sensitivity to those stimulus dimensions that provide behaviorally relevant information. To derive social information from chemosensory cues, sensory systems must embed information about the relationships between behaviorally relevant traits of individuals and the distributions of the chemical cues that are informative about these traits. In simple cases, the mere presence of one particular compound is sufficient to guide appropriate behavior. However, more generally, chemosensory information is conveyed via relative levels of multiple chemical cues, in non-trivial ways. The computations and networks needed to derive information from multi-molecule stimuli are distinct from those required by single molecule cues. Our current knowledge about how socially relevant information is encoded by chemical blends, and how it is extracted by chemosensory systems is very limited. This manuscript explores several scenarios and the neuronal computations required to identify them.
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Affiliation(s)
- Yoram Ben-Shaul
- Department of Medical Neurobiology, Hebrew University Medical School Jerusalem, Israel
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12
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Fu X, Yan Y, Xu PS, Geerlof-Vidavsky I, Chong W, Gross ML, Holy TE. A Molecular Code for Identity in the Vomeronasal System. Cell 2015; 163:313-23. [PMID: 26435105 PMCID: PMC4642884 DOI: 10.1016/j.cell.2015.09.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/30/2015] [Accepted: 08/06/2015] [Indexed: 10/23/2022]
Abstract
In social interactions among mammals, individuals are recognized by olfactory cues, but identifying the key signals among thousands of compounds remains a major challenge. To address this need, we developed a new technique, component-activity matching (CAM), to select candidate ligands that "explain" patterns of bioactivity across diverse complex mixtures. Using mouse urine from eight different sexes and strains, we identified 23 components to explain firing rates in seven of eight functional classes of vomeronasal sensory neurons. Focusing on a class of neurons selective for females, we identified a novel family of vomeronasal ligands, steroid carboxylic acids. These ligands accounted for much of the neuronal activity of urine from some female strains, were necessary for normal levels of male investigatory behavior of female scents, and were sufficient to trigger mounting behavior. CAM represents the first step toward an exhaustive characterization of the molecular cues for natural behavior in a mammalian olfactory system.
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Affiliation(s)
- Xiaoyan Fu
- Department of Anatomy and Neurobiology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Yuetian Yan
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Pei S Xu
- Department of Anatomy and Neurobiology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ilan Geerlof-Vidavsky
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Wongi Chong
- Department of Anatomy and Neurobiology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Timothy E Holy
- Department of Anatomy and Neurobiology, Washington University in St. Louis, St. Louis, MO 63110, USA.
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13
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Haga-Yamanaka S, Ma L, Yu CR. Tuning properties and dynamic range of type 1 vomeronasal receptors. Front Neurosci 2015; 9:244. [PMID: 26236183 PMCID: PMC4501179 DOI: 10.3389/fnins.2015.00244] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 06/26/2015] [Indexed: 11/29/2022] Open
Abstract
The mouse vomeronasal organ (VNO) expresses chemosensory receptors that detect intra-species as well as inter-species cues. The vomeronasal neurons are thought to be highly selective in their responses. The tuning properties of individual receptors remain difficult to characterize due to the lack of a robust heterologous expression system. Here, we take a transgenic approach to ectopically express two type 1 vomeronasal receptors in the mouse VNO and characterize their responses to steroid compounds. We find that V1rj2 and V1rj3 are sensitive to two sulfated estrogens (SEs) and can be activated by a broad variety of sulfated and glucuronidated steroids at high concentrations. Individual neurons exhibit narrow range of concentration-dependent activation. Collectively, a neuronal population expressing the same receptor covers a wide dynamic range in their responses to SEs. These properties recapitulate the response profiles of endogenous neurons to SEs.
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Affiliation(s)
| | - Limei Ma
- Stowers Institute for Medical Research Kansas City, MO, USA
| | - C Ron Yu
- Stowers Institute for Medical Research Kansas City, MO, USA ; Department of Anatomy and Cell Biology, University of Kansas Medical Center Kansas City, KS, USA
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14
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Stowers L, Kuo TH. Mammalian pheromones: emerging properties and mechanisms of detection. Curr Opin Neurobiol 2015; 34:103-9. [PMID: 25747731 DOI: 10.1016/j.conb.2015.02.005] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 02/11/2015] [Accepted: 02/13/2015] [Indexed: 12/22/2022]
Abstract
The concept of mammalian pheromones was established decades before the discovery of any bioactive ligands. Therefore, their molecular identity, native sources, and the meaning of their detection has been largely speculative. There has been recent success in identifying a variety of candidate mouse pheromones and other specialized odors. These discoveries reveal that mammalian pheromones come in a variety of ligand types and they are detected by sensory neurons that are pre-set to promote an array of social and survival behaviors. Importantly, recent findings show that they activate molecularly diverse sensory neurons that differ from canonical odorant detectors. These novel sensory neurons hold future promise to unlock the mystery of how their detection is hardwired to generate behavior.
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Affiliation(s)
- Lisa Stowers
- Department of Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Tsung-Han Kuo
- Department of Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA.
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15
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Abstract
Olfaction has often been described as a ‘synthetic’ sense. A study now reveals a surprising capacity to resolve individual odorants in complex mixtures, with implications for how the nervous system recognizes objects.
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Affiliation(s)
- Timothy E Holy
- Department of Anatomy &Neurobiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, USA
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16
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An olfactory cocktail party: figure-ground segregation of odorants in rodents. Nat Neurosci 2014; 17:1225-32. [PMID: 25086608 PMCID: PMC4146660 DOI: 10.1038/nn.3775] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 07/03/2014] [Indexed: 11/17/2022]
Abstract
In odorant-rich environments, animals must be able to detect specific odorants of interest against variable backgrounds. However, several studies have suggested that both humans and rodents are very poor at analyzing the components of odorant mixtures, leading to the idea that olfaction is a synthetic sense in which mixtures are perceived holistically. We have developed a behavioral task to directly measure the ability of mice to perceive mixture components and found that mice can be easily trained to detect target odorants embedded in unpredictable and variable mixtures. We imaged the responses of olfactory bulb glomeruli to the individual odors used in the task in mice expressing the Ca++ indicator GCaMP3 in olfactory receptor neurons. By relating behavioral performance to the glomerular response patterns, we found that the difficulty of segregating the target from the background was strongly dependent on the extent of overlap between the representations of the target and the background odors by olfactory receptors. Our study indicates that the olfactory system has powerful analytic abilities that are constrained by the limits of combinatorial neural representation of odorants at the level of the olfactory receptors.
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17
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A family of nonclassical class I MHC genes contributes to ultrasensitive chemodetection by mouse vomeronasal sensory neurons. J Neurosci 2014; 34:5121-33. [PMID: 24719092 DOI: 10.1523/jneurosci.0186-14.2014] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The mouse vomeronasal organ (VNO) has a pivotal role in chemical communication. The vomeronasal sensory neuroepithelium consists of distinct populations of vomeronasal sensory neurons (VSNs). A subset of VSNs, with cell bodies in the basal part of the basal layer, coexpress Vmn2r G-protein-coupled receptor genes with H2-Mv genes, a family of nine nonclassical class I major histocompatibility complex genes. The in vivo, physiological roles of the H2-Mv gene family remain mysterious more than a decade after the discovery of combinatorial H2-Mv gene expression in VSNs. Here, we have taken a genetic approach and have deleted the 530 kb cluster of H2-Mv genes in the mouse germline by chromosome engineering. Homozygous mutant mice (ΔH2Mv mice) are viable and fertile. There are no major anatomical defects in their VNO and accessory olfactory bulb (AOB). Their VSNs can be stimulated with chemostimuli (peptides and proteins) to the same maximum responses as VSNs of wild-type mice, but require much higher concentrations. This physiological phenotype is displayed at the single-cell level and is cell autonomous: single V2rf2-expressing VSNs, which normally coexpress H2-Mv genes, display a decreased sensitivity to a peptide ligand in ΔH2Mv mice, whereas single V2r1b-expressing VSNs, which do not coexpress H2-Mv genes, show normal sensitivity to a peptide ligand in ΔH2Mv mice. Consistent with the greatly decreased VSN sensitivity, ΔH2Mv mice display pronounced deficits in aggressive and sexual behaviors. Thus, H2-Mv genes are not absolutely essential for the generation of physiological responses, but are required for ultrasensitive chemodetection by a subset of VSNs.
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18
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Reliable sex and strain discrimination in the mouse vomeronasal organ and accessory olfactory bulb. J Neurosci 2013; 33:13903-13. [PMID: 23966710 DOI: 10.1523/jneurosci.0037-13.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Animals modulate their courtship and territorial behaviors in response to olfactory cues produced by other animals. In rodents, detecting these cues is the primary role of the accessory olfactory system (AOS). We sought to systematically investigate the natural stimulus coding logic and robustness in neurons of the first two stages of accessory olfactory processing, the vomeronasal organ (VNO) and accessory olfactory bulb (AOB). We show that firing rate responses of just a few well-chosen mouse VNO or AOB neurons can be used to reliably encode both sex and strain of other mice from cues contained in urine. Additionally, we show that this population code can generalize to new concentrations of stimuli and appears to represent stimulus identity in terms of diverging paths in coding space. Together, the results indicate that firing rate code on the temporal order of seconds is sufficient for accurate classification of pheromonal patterns at different concentrations and may be used by AOS neural circuitry to discriminate among naturally occurring urine stimuli.
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