Elena Ritschard (Department of Neurosciences and Developmental Biology, Faculty of Life Sciences) received the Award of Excellence for her dissertation: „Evolutionary origins and functional impact of novel genes on cephalopod developmental and morphological innovations“.
Coleoid cephalopods (i.e., octopuses, squids, cuttlefishes) have the largest and most elaborate nervous system among invertebrates and lineage-specific organs associated with the adaptation to different marine environments. This makes them exciting systems to study the evolution of developmental and morphological novelties. With the increasing sequencing of cephalopod genomes, the genomic signatures underlying the evolution of such novelties have begun to be unravelled, but how exactly genomic innovation translates into organismal organisation remains largely unresolved. In her PhD thesis, Elena Ritschard investigated the evolution of genomic novelties in cephalopods at the coding sequence level in order to assess their collective functional impact at the organismal level.
During her thesis work, she identified unique expansions of G protein-coupled receptors (GPCRs) and Cys2His2-type (C2H2) zinc finger transcription factors in cephalopods. Cephalopod GPCR genes, in contrast to their conserved counterparts, show novel domains of expression outside the brain, while expanded C2H2s maintain an ancestral expression in nervous tissues, particularly the brain. The research also identifies cephalopod-, octopus/squid-, and species-specific orphan genes expressed in various tissues, with overlapping expression observed in nervous tissues and early developmental stages. The findings suggest a synergic contribution of cephalopod-specific genes to the unique structure of the cephalopod nervous system and provide a foundation for future functional studies on these organisms' evolution.
The thesis was supervised by Dr Oleg Simakov (University of Vienna) and Dr Graziano Fiorito (Stazione Zoologica Anton Dohrn, Naples, Italy).
We congratulate her on this achievement!