Early social learning triggers neurogenomic expression changes in a swordtail fish

Area of Science:

• Evolutionary biology
• Neuroscience
• Genomics

Background:

• Mate choice is a key driver of reproductive isolation between species.
• Social experience during development influences mating preferences, particularly olfactory cues.
• Swordtail fish (Xiphophorus malinche) provide a model for studying the genetic basis of mate choice.

Purpose of the Study:

• To investigate how social experience with adult olfactory signals affects olfactory preference in Xiphophorus malinche.
• To identify genes and biological pathways differentially expressed in response to conspecific and heterospecific olfactory exposure.
• To explore the role of vomeronasal receptors in species-specific pheromone detection and reproductive isolation.

Main Methods:

• Transcriptome-wide gene expression analysis of sensory and brain tissues.
• Comparison of gene expression between three groups of female fish: no adult exposure, conspecific exposure, and heterospecific exposure.
• Bioinformatic analysis to identify differentially expressed genes and pathways.

Main Results:

• Social experience significantly alters olfactory preference in swordtail fish.
• Differential gene expression was observed between control and exposed groups, as well as between conspecific and heterospecific exposure groups.
• Specific genes and pathways related to olfactory signaling and neural function were identified.

Conclusions:

• Olfactory preference in Xiphophorus malinche is plastic and shaped by early social experience.
• Vomeronasal receptor type 2 paralogs are implicated in detecting species-specific pheromones.
• These findings suggest a molecular mechanism contributing to reproductive isolation between swordtail fish species.