Abstract
The entomopathogenic oomycete Lagenidium giganteum is known to infect and kill mosquito larvae and therefore has been seen as a potential biological control agent against disease vector mosquitoes. Phylogenetic analyses have consistently demonstrated that L. giganteum is a close relative to plant pathogens (Phytophthora and Pythium spp.). In addition, a recent transcriptome analysis showed that L. giganteum expresses oomycete genes that have been associated with plant infection. These observations suggest that L. giganteum might have evolved from a plant pathogen to an invertebrate pathogen, and have retained the ability to establish symbiotic or pathogenic interactions with plant tissues. To test this hypothesis, a metagenomic survey of plant material has been initiated. Specifically, water samples collected from plant axils were processed for metagenomic DNA extraction, and Polymerase Chain Reactions (PCR) were performed in an effort to detect L. giganteum. These PCR reactions used a L. giganteum-specific primer set that was designed to selectively amplify a fragment of the cytochrome c oxidase subunit one (cox1) gene. The cox1 gene sequence has been previously used to barcode oomycetes, and is the default DNA barcode approved by the Consortium for the Barcode of Life (CBOL). Preliminary results indicated that the L. giganteum cox1 gene can be readily amplified and sequenced from metagenomic DNA isolated from plant axil water samples, suggesting that this oomycete is able to colonize environments that are consistent with a close relationship to plant tissues. These results provide a basis to explain a proposed evolution from plant pathogen to entomopathogen.
Faculty Sponsors
Dr. Aurelien Tartar
Project Type
Event
Location
Alvin Sherman Library
Start Date
4-8-2016 1:00 PM
End Date
4-8-2016 5:30 PM
Detection of Lagenidium giganteum in Plant Axil Metagenomes
Alvin Sherman Library
The entomopathogenic oomycete Lagenidium giganteum is known to infect and kill mosquito larvae and therefore has been seen as a potential biological control agent against disease vector mosquitoes. Phylogenetic analyses have consistently demonstrated that L. giganteum is a close relative to plant pathogens (Phytophthora and Pythium spp.). In addition, a recent transcriptome analysis showed that L. giganteum expresses oomycete genes that have been associated with plant infection. These observations suggest that L. giganteum might have evolved from a plant pathogen to an invertebrate pathogen, and have retained the ability to establish symbiotic or pathogenic interactions with plant tissues. To test this hypothesis, a metagenomic survey of plant material has been initiated. Specifically, water samples collected from plant axils were processed for metagenomic DNA extraction, and Polymerase Chain Reactions (PCR) were performed in an effort to detect L. giganteum. These PCR reactions used a L. giganteum-specific primer set that was designed to selectively amplify a fragment of the cytochrome c oxidase subunit one (cox1) gene. The cox1 gene sequence has been previously used to barcode oomycetes, and is the default DNA barcode approved by the Consortium for the Barcode of Life (CBOL). Preliminary results indicated that the L. giganteum cox1 gene can be readily amplified and sequenced from metagenomic DNA isolated from plant axil water samples, suggesting that this oomycete is able to colonize environments that are consistent with a close relationship to plant tissues. These results provide a basis to explain a proposed evolution from plant pathogen to entomopathogen.
