COMPARISON OF THE COMPLETE NUCLEOTIDE SEQUENCES OF MITOCHONDRIAL DNA FROM WISTAR AND OXYS RAT STRAINS MAINTAINED AT THE INSTITUTE OF CYTOLOGY AND GENETICS SB RAS

The study was performed with complete nucleotide sequences of the mitochondrial DNA of Wistar rats and prematurely aging OXYS rats, sensitive to the cataractogenic effect of galactose, kept at the Gene pool of laboratory animals shared access center, Institute of Cytology and Genetics (ICG) of the Siberian Branch of the Russian Academy of Sciences. The nucleotide sequences were submitted to GenBank. It was shown that two additional unique nucleotide substitutions between rats OXYS (ICG) and Wistar (ICG) were absent from other known nucleotide sequences of rat mitochondrial DNA of rats and that they did not cause amino acid substitutions, so that all phenotypic differences between the lines were determined only by differences in their nuclear DNA. The comparative analysis showed that Wistar (ICG) rats had a significant number of nucleotide substitutions compared to rat strains derived from an outbred Wistar colony. This observation contradicts the conjectured relationship of Wistar (ICG) rats to the original Wistar rat stock or its descendants. It is assumed that the Wistar (ICG) rats had descended from the Sprague Dawley rat line, at least, through female lineage

A neurotoxic insecticide promotes fungal infection in Aedes aegypti larvae by altering the bacterial community

Symbiotic bacteria have a significant impact on the formation of defensive mechanisms against fungal pathogens and insecticides. The microbiome of the mosquito Aedes aegypti has been well studied; however, there are no data on the influence of insecticides and pathogenic fungi on its structure. The fungus Metarhizium robertsii and a neurotoxic insecticide (avermectin complex) interact synergistically, and the colonization of larvae with hyphal bodies is observed after fungal and combined (conidia + avermectins) treatments. The changes in the bacterial communities (16S rRNA) of Ae. aegypti larvae under the influence of fungal infection, avermectin toxicosis, and their combination were studied. In addition, we studied the interactions between the fungus and the predominant cultivable bacteria in vitro and in vivo after the coinfection of the larvae. Avermectins increased the total bacterial load and diversity. The fungus decreased the diversity and insignificantly increased the bacterial load. Importantly, avermectins reduced the relative abundance of Microbacterium (Actinobacteria), which exhibited a strong antagonistic effect towards the fungus in in vitro and in vivo assays. The avermectin treatment led to an increased abundance of Chryseobacterium (Flavobacteria), which exerted a neutral effect on mycosis development. In addition, avermectin treatment led to an elevation of some subdominant bacteria (Pseudomonas) that interacted synergistically with the fungus. We suggest that avermectins change the bacterial community to favor the development of fungal infection