Speakers: Marc Libault, PhD
Marc Libault, PhD
Professor, Division of Plant Science and Technology
University of Missouri-Columbia
Dr. Marc Libault is a Professor in the Division of Plant Science and Technology, and a member of the Interdisciplinary Plant Group at the University of Missouri-Columbia (USA). He received his Ph.D. degree in 2004 from the University of Paris-Sud in Plant Cellular and Molecular Biology working on the HP1-like protein in Arabidopsis thaliana. In 2005, he joined Dr. Gary Stacey’s laboratory at the University of Missouri-Columbia as a post-doctoral associate to study the symbiotic interaction between the soybean root and the nitrogen-fixing bacteria, Rhizobia. In 2011, as a faculty at the University of Oklahoma, Dr. Libault developed a system biology approach on the root hair cell, a unique plant root cell type involved in the uptake of water and nutrients from the soil and the first cell infected by Rhizobia in legume plants. In 2018, he joined the University of Nebraska-Lincoln, and pioneered the field of plant single-nucleus technologies to analyze the differential use of the genomic information between plant cells. As a faculty at the University of Missouri-Columiba, he is expanding the use of plant single-nucleus biology to study various species and stresses including legumes to study their symbiosis with nitrogen-fixing bacteria.
Towards a System-Level Understanding of Soybean-Rhizobia Symbiosis at the Single Cell Level
Each plant cell is characterized by its specific function, developmental stage, and interaction with its environment. Understanding the differential use of the genome by each cell/cell type composing the plant and its regulation in response to environmental changes provides a new understanding of gene function, regulation, and networks. In this presentation, focusing on the symbiotic interaction between soybean plants and Bradyrhizobium diazoefficiens, nitrogen-fixing symbiotic bacteria, we will present the use of single-cell omics and high-resolution spatial transcriptomics to 1) reveal the cellular complexity of the infection zone of the soybean nodule, 2) expose the role of the sub-cellular compartmentalization of plant transcripts as a regulatory mechanism of protein translation, and 3) support the functional characterization of new genes controlling this symbiosis. For instance, we will present the role of the nanodomain-associated protein GmFWL3 in controlling the infection of the soybean cells of the nodule by B. diazoefficiens. We will also present our data in the context of Tabula Glycine, a single-cell resolution transcriptome atlas of the soybean plant. For instance, the mining of Tabula Glycine supports the selection of meaningful transcription factor genes that likely cooperate to drive cell-type-specific transcriptomic programs in the B. diazoefficiens-infected soybean cells of the nodule.