Oral Presentation 46th Lorne Genome Conference 2025

Unlocking the seed germination: insights into gene regulation and cell function during Arabidopsis seed-to-seedling transition (113699)

Lim Chee Liew 1 2 , Yue You 3 4 , Lucas Auroux 1 , Marina Oliva 5 , Marta Peirats-Llobet 1 , Sophia Ng 1 6 , Muluneh Tamiru-Oli 1 6 , Oliver Berkowitz 1 6 , Uyen Vu Thuy Hong 1 , Asha Haslem 1 , Tim Stuart 7 , Matthew E. Ritchie 3 4 , George W. Bassel 8 , Ryan Lister 5 9 , James Whelan 1 6 10 , Quentin Gouil 1 3 4 , Mathew G. Lewsey 1 5 6
  1. La Trobe Institute for Agriculture and Food, Bundoora, VIC, Australia
  2. La Trobe University, Bundoora, VIC, Australia
  3. Epigenetics and Development Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
  4. Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
  5. Australian Research Council Centre of Excellence in Plants for Space, La Trobe University, Bundoora, VIC, Australia
  6. Australian Research Council Research Hub for Medicinal Agriculture, La Trobe University, Bundoora, VIC, Australia
  7. Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore, Republic of Singapore
  8. School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
  9. Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre and Centre for Medical Research, The University of Western Australia, , Perth, , Western Australia, , Australia
  10. College of Life Sciences, , Zhejiang University, , Hangzhou, People’s Republic of China

Seeds are crucial to global food production, providing 70% of resources and initiating the lifecycle of most crops through germination. Uniform germination is essential for optimal plant spacing and harvest timing. Despite the significance of this process, the regulation of seed germination remains poorly understood, hindering advancements in improving seed properties. Traditional bulk-tissue 'omics approaches have identified key transcription factors that influence gene expression and germination progression. However, seeds are complex structures with diverse tissues and cell types, each exhibiting distinct functions and gene expression changes that are context-dependent during germination. To gain deeper insights, we have employed single-cell transcriptomic to analyze germinating seeds in the model plant Arabidopsis. Time-series analyses were conducted at three intervals post-stratification: 12 hours (mucilage excretion), 24 hours (seed coat rupture), and 48 hours (embryonic emergence). This approach allowed for the identification and annotation of individual cell types within the embryo and their transcriptional changes during the first 48 hours of germination. We discovered a common transcriptional state at 12 hours before a dynamic transcriptional landscape where cells undergo extensive reprogramming, transitioning through various states to fulfill functional requirements during germination. Unique gene regulatory programs and specific transcription factors were identified for different cell types. This research offers unprecedented insights into the gene regulatory networks that operate during seed germination, enhancing our understanding of cell function during seed-to-seedling transition. Ultimately, these discoveries hold promise for developing strategies to improve the seed-to-seedling transition, ensuring uniform germination at optimal times.