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Single Cell Micro-aspiration as an Alternative Strategy to Fluorescence-activated Cell Sorting for Giant Virus Mixture Separation
Published on: October 27, 2019
Proteorhodopsin genes in giant viruses.
Natalya Yutin1, Eugene V Koonin
1National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
Biology Direct
|October 6, 2012
Summary
Giant viruses infecting marine eukaryotes possess novel proteorhodopsins, potentially acquired from protists. These viral proteins may influence host cell light-dependent signaling and behavior like phototaxis.
Area of Science:
- Virology
- Marine Biology
- Microbial Ecology
Background:
- Large-genome viruses encode proteins that modulate host cell functions beyond basic virus replication.
- Giant viruses, including Phycodnaviridae, infect unicellular eukaryotes and possess extensive gene repertoires.
Purpose of the Study:
- To identify and characterize novel proteins encoded by giant viruses.
- To investigate the origin and potential function of these viral proteins in marine ecosystems.
Main Methods:
- Bioinformatic analysis of giant virus genomes.
- Metagenomic data mining of marine microbial communities.
- Phylogenetic analysis of viral protein sequences.
Main Results:
- Discovery of predicted proteorhodopsins in Organic Lake Phycodnaviruses and Phaeocystis globosa virus, previously undetected in viruses.
- Identification of abundant putative viral proteorhodopsins in marine metagenomic datasets.
- Phylogenetic evidence suggests horizontal gene transfer of proteorhodopsins from protists to giant viruses.
Conclusions:
- Giant viruses encode sensory rhodopsin homologs, likely acquired via horizontal gene transfer.
- Viral proteorhodopsins are widespread in marine environments and may function in light-dependent signaling, potentially influencing host phototaxis.
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