A sturgeon's appetite, decoded: two genes that switch on after lunch

Siberian sturgeon are farmed around the world for meat and caviar, yet nobody knew how these fish sense they have eaten enough. A team at Chengdu Agricultural College in China has now identified two forms of a gene linked to appetite, called pmcha and pmchb. In young sturgeon, both genes became more active in the brain's feeding centre within an hour of a meal, and quieter after a day without food — a pattern suggesting they help signal fullness. The same genes behaved in the opposite rhythm in the liver, hinting they also help the body manage energy between meals. The researchers are clear this is early, basic research, and that more work is needed before it can guide how fish are fed. But it is a first map of hunger in a fish that people have farmed for decades without one.

SDG 2 · Zero hunger — Mechanism: tech innovation