Attention-deficit/hyperactivity disorder (ADHD), marked by excessive activity and impulsivity, is linked to changes in the brain's dopamine system, though the mechanisms remain unclear. Researchers in Japan investigated the role of N-ethylmaleimide-sensitive factor (NSF), a protein linked to dopamine receptors, in D2 receptor-expressing cells. Using genetically modified mice, they found that loss of NSF led to lower dopamine levels and ADHD-like behaviors, offering insight into how brain changes may contribute to ADHD and informing future treatments.

Kyoto, Japan -- The development of cooking was a major milestone in the evolution of human civilization, as it made our food easier to digest and thus more energy efficient. Heating our food can also kill harmful pathogens, and simply makes certain foods taste better. Overcooking, on the other hand, can have adverse effects, particularly on proteins.

Severe heating can modify proteins in a way that reduces their nutritional value. For this reason we do not tend to overcook our food, but some of the processed food we now consume may be subject to severe heating during production.

Scientists have suspected that a diet including high-temperature-treated proteins may have nutritional deficiencies, yet how exactly long-term intake of these treated proteins affects physiological and behavioral responses has not been well understood. This motivated a team of researchers at Kyoto University to investigate how such a diet would affect mice.

Mars once had abundant liquid water, yet orbiters and rovers have found far less carbonate rock than expected for a planet that may have had a thick, carbon dioxide-rich atmosphere. A new geochemical modelling study led by Chang-Chin Wang, with Professor Tomohiro Usui at JAXA and the University of Tokyo, and Associate Professor Mohit Melwani Daswani at ELSI, shows that the type of rock water reacts with, not just water itself, controls whether calcium/iron-rich or magnesium-rich carbonates form. Feldspar-rich rocks, increasingly detected on the Martian surface, readily produce the calcium/iron-rich carbonates seen in many locations. The simulations also show how percolating groundwater could be quietly burying carbonates underground, helping explain their apparent scarcity on the surface.

A team led by researchers from the University of Osaka has revealed the first structure of an umami taste receptor. They found that the pufferfish receptor can sense many more amino acids than the human receptor, including some linked to flavors humans detect as sweet. This helps the fish to detect more types of savory chemicals in their food. The research also shows how the receptor’s structure makes this flexibility possible. The findings could help develop new umami flavors.