Horizontal Gene Transfer in Plants and Algae

Research Focus

Horizontal gene transfer (HGT) is the processes by which genes are passed between distantly related species. These gene transfers may be rare, but provide a mechanism for rapid cellular innovation, allowing organisms to adapt to their environments and acquire new cellular traits. Although this process is well characterized in bacteria, where HGT plays an important role in adaptation and antibiotic resistance, its impact on eukaryotic cells remains unclear. In particular, the frequencies of these transfers, their mechanisms of integration, and their functional contributions to eukaryotic biology and evolution have yet to be understood.

Our goal is to understand the nature of horizontal gene transfer in eukaryotes by combining large-scale phylogenomics with high-throughput genetics in model organisms including Arabidopsis, Marchantia, and Chlamydomonas. In doing so, we hope to understand the role of HGT in the ancient and recent evolution of plants, the implications of HGT in different cellular contexts (e.g., multicellular and single-celled organisms), and the contributions of HGT to phenotypic evolution – from environmental adaptation to the establishment of symbioses, and emergence of new cellular biology.

Selected Publications

Irwin, N. A. T., Pittis, A. A., Richards, T. A., & Keeling, P. J. 2022. Systematic evaluation of horizontal gene transfer between eukaryotes and viruses. Nature Microbiology. 7:327–336. doi: 10.1038/s41564-021-01026-3

Irwin, N. A. T., Pittis, A. A., Mathur, V., Howe, L. J., Keeling P. J., Lynn, D. H., & Bourland, B. A. 2021. The functional diversity and evolution of motile DNA replication systems in ciliates. Current Biology. 31:66-76. doi: 10.1016/j.cub.2020.09.077

Irwin, N. A. T., Martin, B. J. E., Young, B. P., Browne, M. J. G., Flaus, A., Loewen, C. J. R., Keeling, P. J., & Howe, L. J. 2018. Viral proteins as a potential driver of histone depletion in dinoflagellates. Nature Communications. 9:1535. doi: 10.1038/s41467-018-03993-4