From acquisition to exaptation: the evolutionary life of bacterial genes in plant genomes

Abstract

Land plant evolution has been marked by bursts of novelty, often underpinned by extensive genomic innovation. A key mechanism driving these changes is horizontal gene transfer (HGT), the process by which genes move between species. HGT can accelerate evolutionary change through the rapid introduction of new genes yet its importance in plant biology is only beginning to be understood. In this talk, I will present unpublished data aimed at understanding how bacterial genes are functionalized and co-opted in plant and algal genomes. To understand how foreign genes are established, we have developed a novel experimental evolution model using the green alga Chlamydomonas to track the early activation and domestication of bacterial-derived genes in real time. In parallel, to interpret the long-term co-option of HGTs, we are dissecting the functional evolution of GID1, a key plant hormone receptor that originated from a bacterial enzyme early in plant evolution. Through this work, we aim to provide new insights into the mechanisms and evolutionary impacts of HGT, revealing how gene transfers have shaped eukaryotic complexity and uncovering previously unknown aspects of plant and algal biology.

References

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