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Prus-Frankowska, M.

Publications and source records attributed to Prus-Frankowska, M..

3 recordsLinked to original sources

Limited variation in microbial communities across populations of Macrosteles leafhoppers (Hemiptera: Cicadellidae)

Microbial symbionts play important roles in insect biology, but their diversity, distribution, and dynamics over time across host populations are poorly understood. We surveyed the spatio-temporal distribution of bacterial symbionts in the broadly distributed and economically significant leafhopper genus Macrosteles, with emphasis on Macrosteles laevis, using host and symbiont marker gene amplicon sequencing. The cytochrome oxidase I (COI) gene data revealed no strong genetic differentiation across M. laevis populations, significant levels of heteroplasmy, and multiple cases of parasitoid infections. 16S rRNA data confirmed the universal presence of the ancient nutritional endosymbionts Sulcia and Nasuia and a high prevalence of Arsenophonus. Interestingly, in contrast to most previously surveyed species, in M. laevis we found only occasional cases of infection with facultative endosymbionts and other bacteria. There was no significant variation in symbiont prevalence across populations, or among sampling years for the same population. Facultative endosymbionts including Rickettsia, Wolbachia, Cardinium, and Lariskella, were more common in other Macrosteles species. Combined, our data demonstrate that not all species show clear spatial and temporal variation in genetic structure and microbial prevalence. However, simultaneous characterization of host and symbiont marker gene amplicons in large insect collections can help understand the dynamics of host-microbe interactions.

evolutionary biology↗

Pinpointing the microbiota of tardigrades: what is really there?

Microbiota have been proposed as an important aspect of tardigrade biology, but little is known about their diversity and distribution. Here, we attempted to characterize the microbiota of 44 cultured species of tardigrades using 16S rRNA amplicon sequencing, using different specimen pooling strategies, various DNA extraction kits, and multiple types of controls. We also estimated the number of microbes in samples using synthetic DNA spike-ins. Additionally, we reanalyzed data from previous studies. Our results suggest that the microbial community profiles of cultured tardigrades are dominated by bacterial OTUs and genotypes originating from food, medium, or laboratory reagents. We found microbial strains consistently enriched in certain tardigrades (relative to the culture media and controls), which indicates likely symbiotic associations, but the reads representing putative true tardigrade-associated microbes rarely exceeded 20% of the datasets. Some of the identified tardigrade-associated microbes matched symbionts identified by other studies. However, we also identified serious contamination issues with previous studies of tardigrade microbiome, making some of their conclusions questionable. We conclude that tardigrades are not universally dependent on specialized microbes and highlight the necessary safeguards in future studies of the microbiota of microscopic organisms.

microbiology↗

Genome comparison reveals inversions and alternative evolutionary history of nutritional endosymbionts in planthoppers (Hemiptera: Fulgoromorpha)

The evolutionary success of sap-feeding hemipteran insects in the suborder Auchenorrhyncha was enabled by nutritional contributions from their heritable endosymbiotic bacteria. However, the symbiont diversity, functions, and evolutionary origins in this large insect group have not been broadly characterized using genomic tools. In particular, the origins and relationships among ancient betaproteobacterial symbionts Vidania (in Fulgoromorpha) and Nasuia/Zinderia (in Cicadomorpha) are uncertain. Here, we characterized the genomes of Vidania and Sulcia from three Pyrops planthoppers (family Fulgoridae) to understand their metabolic functions and evolutionary histories. Like in previously characterized planthoppers, these symbionts share nutritional responsibilities, with Vidania providing seven out of ten essential amino acids. Sulcia lineages across the Auchenorrhyncha have a highly conserved genome but with multiple independent rearrangements occurring in an early ancestor of Cicadomorpha or Fulgoromorpha and in a few succeeding lineages. Genomic synteny was also observed within each of the betaproteobacterial symbiont genera Nasuia, Zinderia, and Vidania, but not across them, which challenges the expectation of a shared ancestry for these symbionts. The further comparison of other biological traits strongly suggests an independent origin of Vidania early in the planthopper evolution and possibly of Nasuia and Zinderia in their respective host lineages. Originality-Significance StatementWe sequenced and characterized the genomes of two ancient nutritional symbionts, Sulcia and Vidania, in three species from the genus Pyrops in the species- and symbiont-rich but understudied insect clade, Fulgoromorpha (planthoppers). We describe--for the first time--several independent genome rearrangements in Sulcia, which is often cited as a premier example of extreme genome stability spanning hundreds of millions of years. We also show a global lack of synteny across the genomes of the Auchenorrhynchan betaproteobacterial symbionts (Vidania, Nasuia, and Zinderia). This result is unexpected given previous hypotheses of a common origin for these symbionts >250 million years ago alongside Sulcia. Taken together, we suggest an independent origin of Vidania and possibly of Nasuia and Zinderia symbiont lineages as well. This hypothesis further links the potential acquisition of novel nutritional endosymbiont lineages with the emergence of auchenorrhyncham superfamilies.

genomics↗