Ethological research in Hungary is most often associated with studies on dogs, largely due to the extensive work conducted by researchers at ELTE Eötvös Loránd University. However, recent methodological advancements are shifting the focus towards a less conventional model: the paradise fish. These small, vibrant fish offer unique advantages, such as ease of handling and prolific reproduction, which could revolutionize research in evolution and behavioral genetics.
Researchers at ELTE have spearheaded this transition by sequencing and characterizing the reference genome of the Chinese paradise fish (Macropodus opercularis). This achievement, published in the journal Scientific Data, represents a significant milestone. The paradise fish genome is compact, with only 480Mb distributed across 23 chromosomes and more than 20,000 protein-coding genes. This streamlined genetic architecture positions the paradise fish as an ideal candidate for targeted genome editing and other advanced molecular biology techniques.
The potential of the paradise fish extends beyond its genetic simplicity. In a review published in the Journal of Experimental Zoology B, ELTE researchers envision using this species to explore evolutionary development and uncover the genetic basis of complex behaviors. Such studies are now feasible due to the dramatic reduction in sequencing costs and the widespread availability of sophisticated genome editing technologies.
Historically, the paradise fish was not an unfamiliar model at ELTE's Department of Ethology. In fact, for nearly two decades before the mid-1990s, this species was the department's primary research focus, under the guidance of Professor Vilmos Csányi. Csányi and his team chose the paradise fish because of its complex, repetitive, and genetically encoded behaviors. They meticulously catalogued these behaviors into a species-specific ethogram, providing a detailed account of the fish's behavioral repertoire.
Despite the early promise of this research, progress slowed by the mid-1990s due to a lack of appropriate genetic tools needed to dissect the mechanisms underlying these behaviors. This challenge has now been overcome, thanks to modern genetic technologies. Under the leadership of Professor Ádám Miklósi, the current Head of the Department of Ethology, and in collaboration with Máté Varga's Fishgenetics Research Group, a new research initiative has been launched to revive the paradise fish as a model organism in behavioral genetics.
This renewed effort has involved significant collaboration, including contributions from Shawn Burgess's group at the National Human Genome Research Institute (NHGRI) in the United States, and from Ildikó Szeverényi and László Orbán of the Fish Genomics Research Group at the Hungarian Agricultural and Life Sciences University (MATE). Together, these teams are harnessing cutting-edge genetic tools to unlock the mysteries of paradise fish behavior.
The reintroduction of the paradise fish into ethological research represents a blend of tradition and innovation. By combining decades-old behavioral insights with modern genetic techniques, researchers are poised to make groundbreaking discoveries that could have broad implications for understanding behavior in a wide array of species. This old-new model organism is set to open new avenues in the study of evolution, development, and the genetic foundations of behavior, potentially transforming the field of ethology and beyond.
Source: Eötvös Loránd University