The research team led by Dr. Maria Ina Arnone at Stazione Zoologica Anton Dohrn published a new paper describing the development and characterization of the cells producing the Thyrotropin-releasing hormone (TRH) from early developmental stages to post-metamorphosis juvenile stage.
Sea urchins have a complex development, the embryonic stages are followed by the larva stage, called pluteus. The larva does not resemble the adult, which is produced by metamorphosis. Throughout development, the nervous system becomes more and more complex. Using techniques to visualize mRNAs and proteins, it is possible to identify specific neurons, obtain information on their function and follow their changes over the course of development.
In this study, the research team focused their attention on a specific group of neurons (called TRHergic cells) which produce a homolog of the TRH, a hormone found in the brain controlling thyroid function in mammals. In particular, the researchers identified the TRHergic cells at different developmental stages in the Mediterranean sea urchin species Paracentrotus lividus showing how the number of cells and axons increases and eventually form an extensive net of TRHergic neurons. Such net colonizes almost all juvenile’s structures, including spines and tube feet.
Finally, the researchers identified other genes expressed by the TRHergic cells in the P. lividus and compared these cells with the TRHergic cells in other sea urchins: Strongylocentrotus purpuratus, Arbacia lixula and Heliocidaris tuberculata; thus they investigated how these neurons evolved.
The paper has been published in Frontiers in Neuroscience
(https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2024.1378520/full), and it was performed in Dr. Arnone’s laboratory at Stazione Zoologica Anton Dohrn by Dr. Maria Cocurullo in collaboration with Dr. Periklis Paganos and Dr. Giovanna Benvenuto.
