Cutting Edge Seminar - Julia Bailey-Serres: Waterproofing plants: Sensing, signaling and response mechanisms
Date:
Friday, May 02, 2014 10:00 - 11:00
Duration:
1 Hour
Categories:
Cutting Edge Seminar
Speaker
Julia Bailey-Serres
University of California, Riverside
Title:
Waterproofing plants: Sensing, signaling and response mechanisms
Host Johannes Hanson
Room KB3A9
Abstract
The development of crops that can survive extreme weather conditions is imperative due to climate change and population growth. Improving plant yields when there is too little or two much water is especially important. Flooding stress, including soil waterlogging and partial to complete submergence, reduces oxygen availability for ATP production, triggering alterations in gene transcription, mRNA translation and energy metabolism. The plant-specific Group VII Ethylene Response Factor (ERF-VII) transcription factors have emerged as pivotal regulators of flooding and low oxygen responses in plants. In rice (Oryza sativa), ERF-VIIs SUB1A and SNORKEL1/2 enable survival or escape of submergence, respectively. In Arabidopsis thaliana, there are five ERF-VIIs, which are unstable under oxygen-replete conditions due to turnover via the N-end rule of targeted proteolysis. As oxygen levels fall, the ERF-VIIs are stabilized and direct the upregulation of genes associated with anaerobic metabolism. Along with transcriptional regulation in oxygen-deprived cells, there is significant post-transcriptional control. As an energy conserving mechanism, mRNA translation is largely repressed by the sequestration of approximately 90% of the cellular transcripts in large cytosolic granular complexes. We recently reported dynamics in the movement of ribosomes along mRNAs and RNA binding protein that binds many cellular mRNAs that are sequestered during hypoxia. This protein-mRNA association is rapidly reversed upon reoxygenation, allowing stored mRNAs to resume translation. Our efforts to understand low oxygen sensing, signaling and response mechanisms are motivated by the ecological and agronomic relevance of flooding biology in light of the challenges of the 21st century.
Mustroph, A., Zanetti, M.E., Jang, C.J., Holtan, H.E., Repetti, P.P., Galbraith, D.W., Girke, T. and Bailey-Serres, J. (2009) Profiling the Arabidopsis translatome in discrete cell types resolves altered cell-specific priorities in response to hypoxia. Proceedings of the National Academy of Sciences, USA. 106(44):18843-18848.
Gibbs, D.J., Lee, S.C., Isa, N.M.,Gramuglia, S., Fukao, T., Bassel, G.W., Correia, C.S, Corbineau, F., Theodoulou, F.L., Bailey-Serres, J. and Holdsworth, M.J. (2011) Homeostatic response to hypoxia is regulated by the N-end rule pathway in plants. Nature 479(7373):415-418.
Fukao, T., Yeung, E. and Bailey-Serres, J. (2012) The submergence tolerance gene, SUB1A, delays leaf senescence under prolonged darkness through hormonal regulation in rice. Plant Physiology. 160:1795–1807.
Juntawong, P., Girke, T., Bazin, J. and Bailey-Serres, J. (2014) Translational dynamics revealed by genome-wide profiling of ribosome footprints in Arabidopsis Proceedings of the National Academy of Sciences, USA. 111(1):E203-12.
Sorenson, R. and Bailey-Serres, J. (2014) Selective mRNA sequestration by OLIGOURIDYLATE BINDING PROTEIN 1 contributes to translational control during hypoxia in Arabidopsis. Proceedings of the National Academy of Sciences, USA. 111(6):2373-2378.
Speaker
Julia Bailey-Serres
University of California, Riverside
Title:
Waterproofing plants: Sensing, signaling and response mechanisms
Host Johannes Hanson
Room KB3A9
Abstract
The development of crops that can survive extreme weather conditions is imperative due to climate change and population growth. Improving plant yields when there is too little or two much water is especially important. Flooding stress, including soil waterlogging and partial to complete submergence, reduces oxygen availability for ATP production, triggering alterations in gene transcription, mRNA translation and energy metabolism. The plant-specific Group VII Ethylene Response Factor (ERF-VII) transcription factors have emerged as pivotal regulators of flooding and low oxygen responses in plants. In rice (Oryza sativa), ERF-VIIs SUB1A and SNORKEL1/2 enable survival or escape of submergence, respectively. In Arabidopsis thaliana, there are five ERF-VIIs, which are unstable under oxygen-replete conditions due to turnover via the N-end rule of targeted proteolysis. As oxygen levels fall, the ERF-VIIs are stabilized and direct the upregulation of genes associated with anaerobic metabolism. Along with transcriptional regulation in oxygen-deprived cells, there is significant post-transcriptional control. As an energy conserving mechanism, mRNA translation is largely repressed by the sequestration of approximately 90% of the cellular transcripts in large cytosolic granular complexes. We recently reported dynamics in the movement of ribosomes along mRNAs and RNA binding protein that binds many cellular mRNAs that are sequestered during hypoxia. This protein-mRNA association is rapidly reversed upon reoxygenation, allowing stored mRNAs to resume translation. Our efforts to understand low oxygen sensing, signaling and response mechanisms are motivated by the ecological and agronomic relevance of flooding biology in light of the challenges of the 21st century.
Mustroph, A., Zanetti, M.E., Jang, C.J., Holtan, H.E., Repetti, P.P., Galbraith, D.W., Girke, T. and Bailey-Serres, J. (2009) Profiling the Arabidopsis translatome in discrete cell types resolves altered cell-specific priorities in response to hypoxia. Proceedings of the National Academy of Sciences, USA. 106(44):18843-18848.
Gibbs, D.J., Lee, S.C., Isa, N.M.,Gramuglia, S., Fukao, T., Bassel, G.W., Correia, C.S, Corbineau, F., Theodoulou, F.L., Bailey-Serres, J. and Holdsworth, M.J. (2011) Homeostatic response to hypoxia is regulated by the N-end rule pathway in plants. Nature 479(7373):415-418.
Fukao, T., Yeung, E. and Bailey-Serres, J. (2012) The submergence tolerance gene, SUB1A, delays leaf senescence under prolonged darkness through hormonal regulation in rice. Plant Physiology. 160:1795–1807.
Juntawong, P., Girke, T., Bazin, J. and Bailey-Serres, J. (2014) Translational dynamics revealed by genome-wide profiling of ribosome footprints in Arabidopsis Proceedings of the National Academy of Sciences, USA. 111(1):E203-12.
Sorenson, R. and Bailey-Serres, J. (2014) Selective mRNA sequestration by OLIGOURIDYLATE BINDING PROTEIN 1 contributes to translational control during hypoxia in Arabidopsis. Proceedings of the National Academy of Sciences, USA. 111(6):2373-2378.