The researchers at the German Cancer Research Center note all multicellular animals have an innate immune system that can recognize hostile invaders. The moment a foreign structure such as bacteria, parasites or fungi are recognized, the cells release small protein molecules that eliminate the attackers.

The scientists said they discovered such a molecule that plays an important role in triggering the innate immune response of the fruit fly Drosophila, mice and even humans.

The researchers -- led by Michael Boutros and collaborating with colleagues at the Center for Scientific National Research in Strasbourg, France -- discovered a protein named Akirin. When Akirin was suppressed, the flies became significantly more susceptible to bacterial infections. And when the scientists knocked down the protein in all body cells, the fly larvae died at an early stage.

Colleagues at Japan's Osaka University investigated the corresponding mouse Akirin and found the same results.

The work is reported in the journal Nature Immunology.