How insects protect themselves against viruses

It is well known that insects transmit many tropical diseases. It is less well known that they themselves can become ill from the infections and even die.

Male fruit fly Drosophila melanogaster (Photography: André Karwath,
Male fruit fly Drosophila melanogaster (Photography: André Karwath,

The fruit fly Drosophila melanogaster has been a favourite of researchers for over a hundred years. They are small, lowly, easy to breed, and are neglected by animal rights activists. Over the years scientists have produced fruit flies that have thousands of genetic defects. On one hand, they are used to understand the mode of action of numerous genes and their encoded proteins that have basically remained unchanged in evolution up to humans. On the other, they are increasingly applied to study the immune systems of insects that transmit infections.

Numerous reseachers have identified two fundamental mechanisms in viral defence of fruit flies, one being RNA-Interferenz and the other a defence mechanism that in its molecular architecture of a “Jak/Stat pathway” closely resembles the innate immune system of humans. To analyse the importance of both pathways for the control of viral replication, we have studied a number of different viruses and found that RNA interference takes on a particularly important role and always contributes to the immune defence independent of the virus, while the Jak/Stat pathway only participates in the defence against some of them.


Kemp C., Mueller S. et al., J Immunol 2013, 190 : 650-658 

Stefanie Jansen, Stefanie Becker (née Müller), and external cooperation partners (see publication)