title: Courtship Pheromone Use in a Model Urodele, the Mexican Axolotl (Ambystoma mexicanum).
abstract: Sex pheromones have been shown to constitute a crucial aspect of salamander reproduction. Until now, courtship pheromones of Salamandridae and Plethodontidae have been intensively studied, but information on chemical communication in other urodelan families is essentially lacking. The axolotl (Ambystoma mexicanum, Ambystomatidae) has a courtship display that suggests a key role for chemical communication in the orchestration of its sexual behavior, but no sex pheromones have yet been characterized from this species. Here we combined whole transcriptome analyses of the male cloaca with proteomic analyses of water in which axolotls were allowed to court to show that male axolotls secrete multiple ca. 20 kDa glycosylated sodefrin precursor-like factor (SPF) proteins during courtship. In combination with phylogenetic analyses, our data show that the male cloaca essentially secretes a courtship-specific clade of SPF proteins that is orthologous to salamandrid courtship pheromones. In addition, we identified an SPF protein for which no orthologs have been described from other salamanders so far. Overall, our study advocates a central role for SPF proteins during the courtship display of axolotls and adds knowledge on pheromone use in a previously unexplored deep evolutionary branch of salamander evolution.
authors: Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium.
authors: Margo
authors: M
authors: Maex
authors: Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium.
authors: Ines
authors: I
authors: Van Bocxlaer
authors: Laboratory of Molecular Immunology, Department of Microbiology and Immunology, KU Leuven - University of Leuven, Minderbroedersstraat 10 - box 1030, B-3000 Leuven, Belgium.
authors: Anneleen
authors: A
authors: Mortier
authors: Laboratory of Molecular Immunology, Department of Microbiology and Immunology, KU Leuven - University of Leuven, Minderbroedersstraat 10 - box 1030, B-3000 Leuven, Belgium.
authors: Paul
authors: P
authors: Proost
authors: Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium.
authors: Franky
authors: F
authors: Bossuyt
mesh_terms: D000558:Ambystoma mexicanum / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001499:Bayes Theorem; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D002988:Cloaca / Q000378:metabolism; D003380:Courtship; D005260:Female; D020869:Gene Expression Profiling; D008297:Male; D013058:Mass Spectrometry; D023421:Models, Animal; D008969:Molecular Sequence Data; D010675:Pheromones / Q000032:analysis / Q000145:classification / Q000378:metabolism*; D010802:Phylogeny; D040901:Proteomics; D016415:Sequence Alignment; D012726:Sexual Behavior, Animal
chemical_list: D010675:Pheromones