Cell Signalling during Pollen-Pistil Interactions: Uncovering Novel Factors required For Mate Selection in Brassicaceae
Plant Science Research Horizons Seminar: guest speaker Dr. Marcus Samuel, Department of Biological Sciences and Director of Greenhouse Operations, University of Calgary.
Online on Zoom. Click here to participate.
Self-incompatibility (SI) response is a genetic mechanism that allows stigmas to reject self or genetically similar (incompatible) pollen, while accepting non-self or cross (compatible) pollen to promote genetic diversity. On the dry stigmas of Brassicaceae, this response is controlled at the stigmatic surface where incompatible pollen are rejected by preventing their hydration and germination. In contrast, compatible pollen are provided the necessary resources by the stigmatic papillary cells to germinate and penetrate the stigma. Through a proteomics approach followed by functional analysis of several candidates, we have identified multiple components downstream of the well-established interaction between the stigma S-receptor kinase and the pollen-encoded SCR/SP11 ligand that converges on the ARC1 E3 ligase. Our observations suggest that the main mode of SI in the stigmatic papillae is through inhibition of vesicle trafficking to the pollen attachment site that is required for pollen germination to occur, thereby blocking growth of self or incompatible pollen. Other ongoing translational research in canola to promote frost-tolerant degreening and to enhance shatter tolerance will also be discussed.
ABOUT THE SPEAKER
Dr. Marcus Samuel is a Professor of Integrative Cell Biology (Plant Biology) in the Department of Biological Sciences and the Director of Greenhouse Operations at the University of Calgary. Dr. Samuel received his PhD in Plant Biology from Brian Ellis’ lab at the University of British Columbia and did his post-doctoral fellowship at the University of Toronto with Daphne Goring, working on self-incompatibility response in Brassicaceae. Dr. Samuel’s NSERC Discovery research program involves understanding cell-cell communication that occurs between the pollen and the stigma that is crucial for successful reproduction in flowering plants. Dr. Samuel’s group is also involved in translational research that focuses on trait improvement in canola through biotechnological solutions. Dr. Samuel is the recipient of the 2017 CD Nelson for outstanding contributions to Plant Biology. Dr. Samuel’s research program is currently supported by Genome Alberta Funds, NSERC-SPG, NSERC-CRD, NSERC-CREATE and industry funding from Frontier Agri-Sciences inc., Roullier Inc. and Nutrien Inc.