Gene regulation of aggression and courtship

• Applicants: Dr. Clemens Küpper; Professorin Dr. Katja Nowick
• Subject Area: Evolution, Anthropology ; Sensory and Behavioural Biology
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 458888506

The mating competition between males has led to extravagant and elaborate behavioural phenotypes. The most successful males are typically dominant and engage in elaborate courtship display. However, some males lack flashy traits but instead have found alternative ways to obtain matings. For these males the loss of the elaborate behavioural phenotypes has been an adaptive evolutionary innovation. Here we propose to characterize the transcriptomic changes associated with the adaptive loss of aggression and courtship. We will investigate changes in transcription dynamics between males with genetically determined mating tactics in an iconic avian system of sexual selection, the Ruff Philomachus pugnax. In Ruffs, three male morphs exist as evolutionary stable strategies: 1) "Independents" aggressively display on leks, 2) non-aggressive "Satellites" co-display with Independents on leks, whereas 3) "Faeders" are female mimics that lack courtship and aggression. The near-discrete behavioural variation is caused by an autosomal inversion containing only about 125 genes. We have five project aims. First, we will create an improved and fully annotated state-of-the-art genome assembly. Second, we will test how the inversion haplotypes alter expression of genes inside and outside the inversion region across different body and brain tissues that are associated with aggression and courtship. Third, we will then use gene network analysis to pinpoint genes with major pleiotropic effects on aggression and courtship and determine the modular structure of transcriptional responses. Fourth, we will test whether the accumulation of mutations in the inversion haplotypes affects alternative splicing and the chromatin availability for transcription. Finally, we will test whether the observed changes in gene expression and regulation are consistent over the ontogeny. Finding the genetic changes associated with variation in complex social behaviour still represents a major challenge for evolutionary and behavioural genomics. We anticipate that the results of this project advance our understanding about the changes in the molecular cascades leading from DNA sequence to phenotype that are underlying the variation in aggression and courtship behaviour.

• DFG Programme: Research Grants