Leishmaniaviruses

Leishmania RNA virus (LRV) is the type species of the genus Leishmaniavirus in the family Totiviridae. The virus persistently infects the protozoan Leishmania. It possesses an icosahedral capsid of approximately 32–33 nm in diameter. The double-stranded RNA genome of LRVs is approximately 5.3 kbp in length and encodes two proteins – the capsid protein and the RNA-dependent RNA polymerase. Its capsid protein has a unique endoribonuclease activity that targets the viral genome in a site-specific manner. The polymerase is expressed as a polyprotein that is processed by a host-encoded cysteine protease. This ancient virus has elaborated a variety of mechanisms to control copy number that has allowed it to co-evolve with its protozoan host. Over 14 species belonging to the genus Leishmaniavirus have been identified in both New World and Old World parasites.