Improving phylogenetic inference of microsporidian Nosema antheraeae among Nosema species with RPB1, α- and β-tubulin sequences

Abstract

The microsporidian Nosema antheraeae is an intracellular parasite that infects the Chinese oak silkmoth, Antheraea pernyi. However, its phylogenetic position among the Nosema isolates is not yet clear. For a better understanding of the phylogenetic relationships between Nosema species, the RPB1, α-tubulin and β-tubulin genes of N. antheraeae were sequenced and analyzed. These data showed that the N. antheraeae clade was a sister to the clade of Nosema bombycis and other  lepidopteran-infecting Nosema spp. Moreover, even if their respective silkmoth hosts, A. pernyi and Bombyx mori, were known to be close relatives (both belong to superfamily, Bombycoidea), N. antheraeae was not more closely related to N. bombycis than to other lepidopteran Nosema species. Therefore, the relationship between silkmoth-infecting Nosema species was not in accordance with the phylogeny of the  silkmoth hosts; this might indicate that cospeciation have few influence on the silkmoth-infecting Nosema spp.

Keywords: Nosema antheraeae, Nosema bombycis, RPB1, tubulin, phylogenetic