Biology subjects

Bocek, M.

Publications and source records attributed to Bocek, M..

2 recordsLinked to original sources

bioRxiv2023

Parallelized screening of virus accessory genes reveals diverse defense and counter-defense mechanisms

Viruses have been evolving host-modifying factors for billions of years. Genomes of bacterial and archaeal viruses are replete with fast-evolving, uncharacterized accessory genes (AGs), most of which likely antagonize host defenses or other viruses1, 2. Systematic investigation of AGs could uncover a multitude of biological mechanisms involved in virus-host competition, but AG identification in genomic databases remains a challenge. We developed an integrated computational and high-throughput discovery platform to identify AGs in virus genomes and assay their functions in complementary phage infection-dependent and -independent contexts. Our approach showcases how phages interact with the principal layers of antiviral immunity, including cell surface modifications, restriction systems, and abortive infection (Abi) mechanisms, which operate simultaneously in the same host. We discovered multiple Enterobacteriophage AGs associated with counter-defense functions that activate rather than inhibit antiviral immunity in cells, including the surprising finding that anti-restriction AGs elicit programmed cell death (PCD) activity of some restriction-modification (R-M) systems. We propose that counter-defense AGs that trigger PCD create a conundrum for phages whereby keeping the AGs causes PCD but losing them exposes the phage to restriction by bacteria. Strategies employed by viruses to avoid this double jeopardy could be an important factor in virus evolution that remains to be explored.

microbiology↗

bioRxiv2021

Phylogenomic and mitogenomic data can accelerate inventorying of tropical beetles during the current biodiversity crisis

Conservation efforts must be evidence-based, so rapid and economically feasible methods should be used to quantify diversity and distribution patterns. We have attempted to overcome current impediments to the gathering of biodiversity data by using integrative phylogenomic and three mtDNA fragment analyses. As a model, we sequenced the Metriorrhynchini beetle fauna, sampled from [~]700 localities in three continents. The species-rich dataset included [~]6,500 terminals, >2,300 putative species, more than a half of them unknown to science. The phylogenomic backbone enabled the integrative delimitation of robustly defined natural units that will inform future research. Using constrained mtDNA analysis, we identified the spatial structure of -diversity, very high species-level endemism, a biodiversity hotspot in New Guinea, and high phylogenetic diversity in the Sundaland. We suggest that [~]20 person months of focused field research and subsequent laboratory and bioinformatic workflow steps would substantially accelerate the inventorying of any hyperdiverse tropical group with several thousand species. The outcome would be a scaffold for the incorporation of further data. The database of sequences could set a benchmark for the spatiotemporal evaluation of biodiversity, would support evidence-based conservation planning, and would provide a robust framework for systematic, biogeographic, and evolutionary studies.

evolutionary biology↗