Abstract
Bats are an important host of various viruses which are deadly to humans and other mammals but do not cause outward signs of illness in bats. Furthering our understanding of the unique features of the immune system of bats will shed light on how they tolerate viral infections, potentially informing novel antiviral strategies in humans and other animals. This study examines the antiviral protein tetherin, which prevents viral particles from escaping their host cell. Analysis of tetherin from 27 bat species reveals that it is under strong evolutionary pressure, and we show that multiple bat species have evolved to possess more tetherin genes than other mammals, some of which encode structurally unique tetherins capable of activity against different viral particles. These data suggest that bat tetherin plays a potentially broad and important role in the management of viral infections in bats.