Single-cell sequencing provides clues about the developmental genetic basis of evolutionary adaptations in syngnathid fishes

• DOI: 10.7554/elife.97764
• Publication Date: 2024-06-05T13:26:19Z
• Authors: Hope M Healey; Hayden B Penn; Clayton M Small; Susan Bassham; Vithika Goyal; Micah A Woods; William A Cresko
• Keywords: non-traditional model; QH301-705.5; Science; Q; R; scRNAseq; evolutionary novelty; Article; evolution of development; Medicine; Syngnathidae; Biology (General); syngnathid fishes; Developmental Biology

Seahorses, pipefishes, and seadragons are fishes from the family Syngnathidae that have evolved extraordinary traits including male pregnancy, elongated snouts, loss of teeth, dermal bony armor. The developmental genetic cellular changes led to evolution these largely unknown. Recent syngnathid genome assemblies revealed suggestive gene content differences provide opportunity for detailed analyses. We created a single cell RNA sequencing atlas Gulf pipefish embryos understand basis four traits: derived head shape, toothlessness, armor, pregnancy. completed marker analyses, built networks, examined spatial expression select genes. identified osteochondrogenic mesenchymal cells in elongating face express regulatory genes bmp4, sfrp1a , prdm16 . found no evidence tooth primordia cells, we observed re-deployment osteoblast networks developing Finally, epidermal expressed nutrient processing environmental sensing genes, potentially relevant brooding environment. evolutionary innovations composed recognizable types, suggesting features originate within existing networks. Future work addressing across multiple stages species is essential understanding how their novelties evolved.