Accepted_test

Полногеномное секвенирование микроспоридий рода Nosema – внутриклеточных паразитов чешуекрылых насекомых
by Malysh S. | Rumiantseva A. | Sakhabeev R. | Efeikin B. | Danilov L. | All-Russian Institute of Plant Protection, Saint Petersburg, Russia | All-Russian Institute of Plant Protection, Saint Petersburg, Russia | St. Petersburg State Institute of Technology, Saint Petersburg, Russia | A.N. Severtsov Institute of Ecology and Evolution, Moscow, Russia | Saint Petersburg State University, Saint Petersburg, Russia
Abstract ID: 670
Event: BGRS-abstracts
Sections: [Sym 1] Section “Structural-functional organization of genomes and transcriptomics”

Microsporidia are protists related to fungi, distributed as parasites of arthropods and other animals. Over 200 microsporidia genera are described, containing about 1300 species, About 50 complete genome sequences are available. The aim of the work was to perform whole-genome sequencing of microsporidian isolates Nosema pyrausta from the European corn borer Ostrinia nubilalis and Nosema sp. NspHA22 from the cotton bollworm Helicoverpa armigera. For large scale spore production, both isolates were propagated in the Siberian silkmoth Dendrolimus sibiricus. The approximate genome size of N. pyrausta was 15.9 Mb, the number of predicted genes was 4468, which is very close to the corresponding indicators of the type species used as the reference - N. bombycis. Meanwhile, other species of Nosema show genome size four times lesser. This allows suggesting that both N. bombycis and N. pyrausta underwent evolutionary event of genome duplication recently. The genome assembly and annotation of NspHA22 is in progress. The raw whole genome data from both newly sequenced microsporidian isolates were used to extract nucleotide sequences of individual genes: heat shock protein HSP70 and RNA polymerase RPB1, as well as hexokinase. The studied microsporidia showed their division into two sister phylogenetic lineages: one including N. bombycis and NspHA22, another - N. pyrausta and N. antheraeae. This makes it possible to fairly clearly distinguish between the studied isolates. Yet, sequencing is necessary for the most closely related forms, as species specific primers could not be designed due to low frequency of nucleotide substitutions.