Thanks to similar biological mechanisms in jellyfish and fruit flies, a feeling of satiety occurs. In this respect informs Tohoku University.
The motivation to eat, that is, the feeling of hunger and satiety, is controlled by hormones and small proteins called neuropeptides. They are found in many organisms, including humans, mice, and fruit flies. In this context, scientists are interested in when exactly this mechanism arose in the course of evolution.
Hiromu Tanimoto and colleagues decided to conduct a comparative study on fruit flies and shell jellyfish. Flies are arthropods, and jellyfish are cnidarians, the last common ancestor of such organisms that lived more than 600 million years ago. At the same time, cladonems can regulate the amount of food consumed depending on the degree of satiety.
To understand the mechanisms underlying feeding regulation, the authors compared gene expression profiles in fasted and fed jellyfish. The saturation state altered the expression levels of many genes, including those encoding neuropeptides. By synthesizing and testing these neuropeptides, we found five that reduced the amount of food in the hungry jellyfish.”
Researchers then figured out how one of these neuropeptides, GLWamide, controls nutrition. Detailed behavioral analysis showed that GLWamid inhibited (suppressed) the shortening of the tentacles, but was essential for transferring captured prey to the mouth. The analysis showed that GLWamid was located at the base of the tentacles and their concentration increased with food consumption.
The scientists then experimented with fruit flies. Their nutrition is regulated by a myoinhibitory peptide (MIP) similar to GLWamide. This gave the authors the idea to genetically engineer flies to express GLWamid and jellyfish to express MIP. In both cases, the “foreign” substance reduced the animal’s food intake, suggesting their limited interchangeability and thus a common origin.
ancient biologists approvedthat the moths’ “tails” act as decoys for bats.