Image of the Day: Nutrient Sensor

A zinc-sensing protein found in fruit fly intestines regulates the insect’s growth and feeding behavior.

Amy Schleunes
Amy Schleunes

A former intern at The Scientist, Amy studied neurobiology at Cornell University and later earned her MFA in creative writing from the University of Iowa. She is a Los...

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Mar 26, 2020
A segment of fruit fly intestine with the Hodor nutrient sensor in green, cell nuclei in blue, and visceral muscle in white

Anewly identified nutrient-sensing protein named Hodor helps regulate both developmental growth and food intake in fruit flies, according to a study published on March 18 in Nature. Found in the intestines, Hodor uses zinc to transport chloride into and out of cells, according to a press release, echoing earlier findings that metal ions are critical to growth and development. When zinc levels were increased in the flies’ food, feeding also increased. In contrast, when Hodor was blocked, feeding decreased. The team believes that the nutrient sensor may help the insects find food sources rich in nutrients, the statement notes, because yeasts commonly found on fruit and other foods produce zinc.

S. Redhai et al., “An intestinal zinc sensor regulates food intake and developmental growth,” Nature, doi:10.1038/S41586-020-2111-5, 2020.

Amy Schleunes is an intern at The Scientist. Email her at