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Kröner L, Lötters S, Hopp MT. Insights into caudate amphibian skin secretions with a focus on the chemistry and bioactivity of derived peptides. Biol Chem 2024; 0:hsz-2024-0035. [PMID: 38766708 DOI: 10.1515/hsz-2024-0035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 05/06/2024] [Indexed: 05/22/2024]
Abstract
Amphibians are well-known for their ability to produce and secrete a mixture of bioactive substances in specialized skin glands for the purpose of antibiotic self-protection and defense against predators. Some of these secretions contain various small molecules, such as the highly toxic batrachotoxin, tetrodotoxin, and samandarine. For some time, the presence of peptides in amphibian skin secretions has attracted researchers, consisting of a diverse collection of - to the current state of knowledge - three to 104 amino acid long sequences. From these more than 2000 peptides many are known to exert antimicrobial effects. In addition, there are some reports on amphibian skin peptides that can promote wound healing, regulate immunoreactions, and may serve as antiparasitic and antioxidative substances. So far, the focus has mainly been on skin peptides from frogs and toads (Anura), eclipsing the research on skin peptides of the ca. 700 salamanders and newts (Caudata). Just recently, several novel observations dealing with caudate peptides and their structure-function relationships were reported. This review focuses on the chemistry and bioactivity of caudate amphibian skin peptides and their potential as novel agents for clinical applications.
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Affiliation(s)
- Lorena Kröner
- Department of Chemistry, Institute for Integrated Natural Sciences, 38899 University of Koblenz , D-56070 Koblenz, Germany
| | - Stefan Lötters
- Department of Biogeography, University of Trier, D-54286 Trier, Germany
| | - Marie-T Hopp
- Department of Chemistry, Institute for Integrated Natural Sciences, 38899 University of Koblenz , D-56070 Koblenz, Germany
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Rato A, Joaquim S, Matias D, Hubbard PC. What do oysters smell? Electrophysiological evidence that the bivalve osphradium is a chemosensory organ in the oyster, Magallana gigas. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2023; 209:391-401. [PMID: 36609922 PMCID: PMC10102104 DOI: 10.1007/s00359-022-01608-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 01/09/2023]
Abstract
The sensing of chemical cues is essential for several aspects of bivalve biology, such as the detection of food and pheromones. However, little is known about chemical communication systems in bivalves or the possible role of the osphradium as a chemosensory organ. To address this, we adapted an electrophysiological technique extensively used in vertebrates-the electro-olfactogram-to record from the osphradium in the Pacific oyster, Magallana gigas. This technique was validated using amino acids as stimulants. The osphradium proved to be sensitive to most proteinogenic L-amino acids tested, evoking tonic, negative, concentration-dependent 'electro-osphradiogram' (EOsG) voltage responses, with thresholds of detection in the range of 10- 6 to 10- 5 M. Conversely, it was insensitive to L-arginine and L-glutamic acid. The current study supports the hypothesis that the osphradium is, indeed, a chemosensory organ. The 'electro-osphradiogram' may prove to be a powerful tool in the isolation and characterization of pheromones and other important chemical cues in bivalve biology.
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Affiliation(s)
- Ana Rato
- Centre of Marine Sciences (CCMAR), University of Algarve, Campus de Gambelas, 8005-139, Faro, Portugal. .,Department of Sea and Marine Resources, Portuguese Institute for Sea and Atmosphere (IPMA, I.P.), Av. 5 de Outubro s/n, 8700-305, Olhão, Portugal.
| | - Sandra Joaquim
- Department of Sea and Marine Resources, Portuguese Institute for Sea and Atmosphere (IPMA, I.P.), Av. 5 de Outubro s/n, 8700-305, Olhão, Portugal.,Interdisciplinary Centre of Marine Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal
| | - Domitília Matias
- Department of Sea and Marine Resources, Portuguese Institute for Sea and Atmosphere (IPMA, I.P.), Av. 5 de Outubro s/n, 8700-305, Olhão, Portugal.,Interdisciplinary Centre of Marine Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal
| | - Peter C Hubbard
- Centre of Marine Sciences (CCMAR), University of Algarve, Campus de Gambelas, 8005-139, Faro, Portugal
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Electrophysiological responses to conspecific odorants in Xenopus laevis show potential for chemical signaling. PLoS One 2022; 17:e0273035. [PMID: 36070316 PMCID: PMC9451071 DOI: 10.1371/journal.pone.0273035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 08/01/2022] [Indexed: 11/19/2022] Open
Abstract
The fully aquatic African clawed frog, Xenopus laevis, has an unusual and highly adapted nose that allows it to separately sample both airborne and waterborne stimuli. The function of the adult water nose has received little study, despite the fact that it is quite likely to receive information about conspecifics through secretions released into the water and could aid the frog in making decisions about social and reproductive behaviors. To assess the potential for chemical communication in this species, we developed an in situ electroolfactogram preparation and tested the olfactory responses of adult males to cloacal fluids and skin secretions from male and female conspecifics. We found robust olfactory responses to all conspecific stimuli, with greatest sensitivity to female cloacal fluids. These results open the door to further testing to identify compounds within cloacal fluids and skin secretions that are driving these responses and examine behavioral responses to those compounds. Understanding the role of chemical communication in social and reproductive behaviors may add to our rich understanding of vocal communication to create a more complete picture of social behavior in this species.
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Naito JI, Kambayashi C, Namba R, Yoshikawa N, Shimizu N. Seasonal Changes in Breeding Characters of Two Syntopic Onychodactylus Salamanders with Special Reference to Differentiation in Their Breeding Seasons. CURRENT HERPETOLOGY 2022. [DOI: 10.5358/hsj.41.196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Affiliation(s)
| | - Chiaki Kambayashi
- Faculty of Bio-Science, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga 526–0829, JAPAN
| | - Renshiro Namba
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima 739–8521, JAPAN
| | - Natsuhiko Yoshikawa
- Department of Zoology, National Museum of Nature and Science, Tokyo, Amakubo 4–1–1, Tsukuba, Ibaraki 305–0005, JAPAN
| | - Norio Shimizu
- Hiroshima University Museum, Higashihiroshima, Hiroshima 739–8524, JAPAN
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Staub NL, Stiller AB, Kiemnec-Tyburczy KM. A New Perspective on Female-to-Male Communication in Salamander Courtship. Integr Comp Biol 2021; 60:722-731. [PMID: 32573720 DOI: 10.1093/icb/icaa087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Courtship behavior in salamanders is often complex and involves well-documented communication from males to females in multiple sensory modalities. Historically, behaviors exhibited during the major stages of courtship have been predominately framed as a male acting and signaling to "persuade" a passive female to participate in courtship and remain with him until sperm release is completed. In this review, we use courtship descriptions for lungless salamanders (Plethodontidae) as a case study to illustrate this historical bias of a male-centered perspective. We then re-examine the literature and summarize the many ways females are active participants during plethodontid courtships. We also relate female behaviors to the types of female-to-male communication that may occur. For example, females have been documented to approach a male and initiate courtship, participate in mutual head rubbing, and step astride the male's tail to begin the tail-straddling walk (a key courtship behavior observed in all plethodontids). Additionally, females have glands that may produce chemical signals that males respond to during courtship. We conclude that communication during courtship is more accurately described as a two-way interaction where each partner's behavior is coordinated with the other's via multi-modal signaling. Shifting the lens through which we view courtship and behavior provides insight into which female behaviors and anatomical features are most likely to be used for communication with males.
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Affiliation(s)
- Nancy L Staub
- Biology Department, Gonzaga University, Spokane, WA 99258, USA
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Woodley SK, Staub NL. Pheromonal communication in urodelan amphibians. Cell Tissue Res 2021; 383:327-345. [PMID: 33427952 DOI: 10.1007/s00441-020-03408-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/15/2020] [Indexed: 01/24/2023]
Abstract
Pheromonal communication is an ancient and pervasive sensory modality in urodelan amphibians. One family of salamander pheromones (the sodefrin precursor-like factor (SPF) family) originated 300 million years ago, at the origin of amphibians. Although salamanders are often thought of as relatively simple animals especially when compared to mammals, the pheromonal systems are varied and complex with nuanced effects on behavior. Here, we review the function and evolution of pheromonal signals involved in male-female reproductive interactions. After describing common themes of salamander pheromonal communication, we describe what is known about the rich diversity of pheromonal communication in each salamander family. Several pheromones have been described, ranging from simple, invariant molecules to complex, variable blends of pheromones. While some pheromones elicit overt behavioral responses, others have more nuanced effects. Pheromonal signals have diversified within salamander lineages and have experienced rapid evolution. Once receptors have been matched to pheromonal ligands, rapid advance can be made to better understand the olfactory detection and processing of salamander pheromones. In particular, a large number of salamander species deliver pheromones across the skin of females, perhaps reflecting a novel mode of pheromonal communication. At the end of our review, we list some of the many intriguing unanswered questions. We hope that this review will inspire a new generation of scientists to pursue work in this rewarding field.
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Affiliation(s)
- Sarah K Woodley
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA.
| | - Nancy L Staub
- Biology Department, Gonzaga University, Spokane, WA, 99203, USA
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Lüddecke T, Schulz S, Steinfartz S, Vences M. A salamander’s toxic arsenal: review of skin poison diversity and function in true salamanders, genus Salamandra. Naturwissenschaften 2018; 105:56. [DOI: 10.1007/s00114-018-1579-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/03/2018] [Accepted: 08/05/2018] [Indexed: 12/16/2022]
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Taylor A, Mills D, Wang T, Ntalamagka N, Cummins SF, Elizur A. A Sperm Spawn-Inducing Pheromone in the Silver Lip Pearl Oyster (Pinctada maxima). MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2018; 20:531-541. [PMID: 29705863 DOI: 10.1007/s10126-018-9824-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 04/03/2018] [Indexed: 06/08/2023]
Abstract
Pheromones are considered to play an important role in broadcast spawning in aquatic animals, facilitating synchronous release of gametes. In oysters, the sperm has been implicated as a carrier for the spawn-inducing pheromone (SIP). In hatchery conditions, male pearl oysters (Pinctata maxima) can be stimulated to spawn through a variety of approaches (e.g. rapid temperature change), while females can only be induced to spawn through exposure to conspecific sperm, thus limiting development of targeted pairing, required for genetic research and management. The capacity for commercial production and improvement of genetic lines of pearl oysters could be greatly improved with access to a SIP. In this study, we prepared and sequenced crude and semi-purified P. maxima sperm extracts that were used in bioassays to localise the female SIP. We report that the P. maxima SIP is proteinaceous and extrinsically associated with the sperm membrane. Bioactivity from pooled RP-HPLC fractions, but not individual fractions, suggests that the SIP is multi-component. We conclude that crude sperm preparations, as described in this study, can be used as a sperm-free inducer of female P. maxima spawning, which enables for a more efficient approach to genetic breeding.
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Affiliation(s)
- A Taylor
- Darwin Aquaculture Centre, Channel Island, Darwin, Northern Territory, 0800, Australia
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - D Mills
- Darwin Aquaculture Centre, Channel Island, Darwin, Northern Territory, 0800, Australia
| | - T Wang
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - N Ntalamagka
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - S F Cummins
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - A Elizur
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia.
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Imorin: a sexual attractiveness pheromone in female red-bellied newts (Cynops pyrrhogaster). Sci Rep 2017; 7:41334. [PMID: 28120945 PMCID: PMC5264602 DOI: 10.1038/srep41334] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 12/16/2016] [Indexed: 11/15/2022] Open
Abstract
The male red-bellied newt (Cynops pyrrhogaster) approaches the female’s cloaca prior to performing any courtship behaviour, as if he is using some released substance to gauge whether she is sexually receptive. Therefore, we investigated whether such a female sexual attractiveness pheromone exists. We found that a tripeptide with amino acid sequence Ala-Glu-Phe is secreted by the ciliary cells in the epithelium of the proximal portion of the oviduct of sexually developed newts and confirmed that this is the major active substance in water in which sexually developed female newts have been kept. This substance only attracted sexually developed male newts and acted by stimulating the vomeronasal epithelial cells. This is the first female sexual attractiveness peptide pheromone to be identified in a vertebrate.
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Hasumi M. Social interactions during the aquatic breeding phase of the family Hynobiidae (Amphibia: Caudata). Acta Ethol 2015. [DOI: 10.1007/s10211-015-0214-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Woodley S. Chemosignals, hormones, and amphibian reproduction. Horm Behav 2015; 68:3-13. [PMID: 24945995 DOI: 10.1016/j.yhbeh.2014.06.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 05/24/2014] [Accepted: 06/09/2014] [Indexed: 11/23/2022]
Abstract
This article is part of a Special Issue "Chemosignals and Reproduction". Amphibians are often thought of as relatively simple animals especially when compared to mammals. Yet the chemosignaling systems used by amphibians are varied and complex. Amphibian chemosignals are particularly important in reproduction, in both aquatic and terrestrial environments. Chemosignaling is most evident in salamanders and newts, but increasing evidence indicates that chemical communication facilitates reproduction in frogs and toads as well. Reproductive hormones shape the production, dissemination, detection, and responsiveness to chemosignals. A large variety of chemosignals have been identified, ranging from simple, invariant chemosignals to complex, variable blends of chemosignals. Although some chemosignals elicit straightforward responses, others have relatively subtle effects. Review of amphibian chemosignaling reveals a number of issues to be resolved, including: 1) the significance of the complex, individually variable blends of courtship chemosignals found in some salamanders, 2) the behavioral and/or physiological functions of chemosignals found in anuran "breeding glands", 3) the ligands for amphibian V2Rs, especially V2Rs expressed in the main olfactory epithelium, and 4) the mechanism whereby transdermal delivery of chemosignals influences behavior. To date, only a handful of the more than 7000 species of amphibians has been examined. Further study of amphibians should provide additional insight to the role of chemosignals in reproduction.
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Affiliation(s)
- Sarah Woodley
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282, United States.
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Kim JK, Kim IH, Heo JH, Lee JH, Ra NY, Eom J, Jeong SM, Lee HJ, Park D. Arginine Vasotocin (AVT) Triggers Courtship Behavior Without Exposure to External Stimuli and Modulates the Olfactory Response of MaleHynobius leechiiSalamanders. Zoolog Sci 2013; 30:929-37. [DOI: 10.2108/zsj.30.929] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Poth D, Wollenberg KC, Vences M, Schulz S. Volatile amphibian pheromones: macrolides from mantellid frogs from Madagascar. Angew Chem Int Ed Engl 2012; 51:2187-90. [PMID: 22266641 DOI: 10.1002/anie.201106592] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 11/18/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Dennis Poth
- Institut für Organische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
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Poth D, Wollenberg KC, Vences M, Schulz S. Flüchtige Pheromone aus Amphibien: Makrolide von Fröschen der Familie Mantellidae aus Madagaskar. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201106592] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Cummins SF, Bowie JH. Pheromones, attractants and other chemical cues of aquatic organisms and amphibians. Nat Prod Rep 2012; 29:642-58. [DOI: 10.1039/c2np00102k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Lim H, Sorensen PW. Polar metabolites synergize the activity of prostaglandin F2α in a species-specific hormonal sex pheromone released by ovulated common carp. J Chem Ecol 2011; 37:695-704. [PMID: 21647722 DOI: 10.1007/s10886-011-9976-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 05/18/2011] [Accepted: 05/24/2011] [Indexed: 11/28/2022]
Abstract
Many species of teleost fish detect and release F prostaglandins (PGFs), but the specific identities of these compounds and how they function as species-specific pheromones have yet to be resolved. This study addressed these questions in the common carp. An initial set of experiments established that mature male common carp were attracted to chemicals released by ovulated conspecifics, whereas the odor of female goldfish, a close relative, was less attractive. Tests of fractionated holding water from ovulated carp revealed that only the non-polar fraction was attractive on its own. Mass spectrometry and immunoassay next demonstrated that the non-polar fraction contained large quantities of prostaglandin F(2α) (PGF(2α)), 15keto-prostaglandinF(2α), and 13,14-dihydro-15keto-prostaglandin F(2α) (100 g fish released over 1 μg of all 3 PGFs per h at a ratio of 1.0: 1.7: 0.7). Ovulated goldfish released the same three PGFs but at a slightly greater rate and in a different ratio. Tests of synthetic mixtures of these PGFs revealed that the carp-specific mixture attracted male carp but was no better than the goldfish-specific mixture or PGF(2α) alone and that PGF(2α) was just as attractive as mixture of all three PGFs. A final set of attraction tests revealed that although PGF(2α) could explain all of the activity of the non-polar portion of female carp holding water, it could not explain the entire activity of female water but that a mixture of PGFs and the polar fraction could. We conclude that ovulated female carp release a multi-component sex pheromone complex that is comprised of PGF(2α) and unknown species-specific polar compound(s) that synergize the activity of the former. The pheromone also might be useful in controlling this invasive species. The observation that a fish hormonal sex pheromone incorporates bodily metabolites in addition to relatively common hormonal products demonstrates a mechanism by which species specificity may be conferred to this common type of sex pheromone.
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Affiliation(s)
- Hangkyo Lim
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, St. Paul, MN 55108, USA
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Pheromonal communication in amphibians. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2010; 196:713-27. [PMID: 20526605 DOI: 10.1007/s00359-010-0540-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 05/03/2010] [Accepted: 05/19/2010] [Indexed: 10/19/2022]
Abstract
Pheromonal communication is widespread in salamanders and newts and may also be important in some frogs and toads. Several amphibian pheromones have been behaviorally, biochemically and molecularly identified. These pheromones are typically peptides or proteins. Study of pheromone evolution in plethodontid salamanders has revealed that courtship pheromones have been subject to continual evolutionary change, perhaps as a result of co-evolution between the pheromonal ligand and its receptor. Pheromones are detected by the vomeronasal organ and main olfactory epithelium. Chemosensory neurons express vomeronasal receptors or olfactory receptors. Frogs have relatively large numbers of vomeronasal receptors that are transcribed in both the vomeronasal organ and the main olfactory epithelium. Salamander vomeronasal receptors apparently are restricted to the vomeronasal organ. To date, no chemosensory ligands have been matched to vomeronasal receptors or olfactory receptors so it is unknown whether particular receptor types are (1) specialized for detection of pheromones versus other chemosignals, or (2) specialized for detection of volatile, nonvolatile, or water-borne chemosignals. Despite progress in understanding amphibian pheromonal communication, only a small fraction of amphibian species have been examined. Study of additional species of amphibians will indicate which traits related to pheromonal communication are evolutionarily conserved and which traits have diverged over time.
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