| Title: | Exaptation as a Mechanism for Functional Reinforcement of an Animal Pheromone System |
| Author(s): | Maex M; Treer D; De Greve H; Proost P; Van Bocxlaer I; Bossuyt F; |
| Address: | "Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium. Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium; VIB-VUB Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, 1050 Brussels, Belgium. Laboratory of Molecular Immunology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Herestraat 49, 3000 Leuven, Belgium. Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium. Electronic address: franky.bossuyt@vub.be" |
| DOI: | 10.1016/j.cub.2018.06.074 |
| ISSN/ISBN: | 1879-0445 (Electronic) 0960-9822 (Linking) |
| Abstract: | "Animal sex pheromone systems often exist as multicomponent signals [1-11] to which chemical cues have been added over evolutionary time. Little is known on why and how additional molecules become recruited and conserved in an already functional pheromone system. Here, we investigated the evolutionary trajectory of a series of 15 kDa proteins-termed persuasins-that were co-opted more recently alongside the ancient sodefrin precursor-like factor (SPF) courtship pheromone system in salamanders [9, 12]. Expression, genomic, and molecular phylogenetic analyses show that persuasins originated from a gene that is expressed as a multi-domain protein in internal organs where it has no pheromone function but underwent gene duplication and neofunctionalization. The subsequent evolution combined domain loss and the introduction of a proteolytic cleavage site in the duplicated gene to give rise to two-domain cysteine rich proteins with structural properties similar to SPF pheromones [12]. An expression shift to the pheromone-producing glands, where expression of persuasins was immediately spatiotemporally synchronized with the already available pheromone system, completed the birth of a new pheromone. Electrostatic forces between members of both protein families likely enhance co-localization and simultaneous activation of different female olfactory neurons, explaining why persuasins immediately had a selective advantage. In line with this, behavioral assays show that persuasins increase female receptivity on their own but also exert a cumulative or synergistic effect in combination with SPF, clearly reinforcing the pheromone system as a whole. Our study reveals molecular remodeling of an existing protein architecture as an evolutionary mechanism for functional reinforcement of animal pheromone systems" |
| Keywords: | "*Adaptation, Biological Amino Acid Sequence Amphibian Proteins/chemistry/*genetics/metabolism Animals Evolution, Molecular Female Male Phylogeny Sequence Alignment Sex Attractants/chemistry/genetics/*physiology Species Specificity Urodela/genetics/*physio;" |
| Notes: | "MedlineMaex, Margo Treer, Dag De Greve, Henri Proost, Paul Van Bocxlaer, Ines Bossuyt, Franky eng Research Support, Non-U.S. Gov't England 2018/09/11 Curr Biol. 2018 Sep 24; 28(18):2955-2960.e5. doi: 10.1016/j.cub.2018.06.074. Epub 2018 Sep 6" |
