You are receiving this e-mail because you subscribed to our seminars announcements and reminders service at [ https://maillist.psb.ugent.be/mailman/listinfo/seminars | https://maillist.psb.ugent.be/mailman/listinfo/seminars ] . '' Plasma Membrane to Proline Metabolism: Signaling and metabolic mechanisms that control plant growth and drought resistance '' Prof Paul E. Verslues Institute of Plant and Microbial Biology Academia Sinica Taipei TAIWAN Monday, May 30, 2022 11:00 In this seminar Prof Paul E. Verslues will present two ongoing projects in our efforts to understand how plants adjust their growth and metabolism in response to moderate severity low water potential (drought) stress. While this type of stress typically does not lead to death of the plant, how the plant responds influences agronomic productivity and ability to adapt to changing environmental conditions. To better understand the role of proline metabolism in drought resistance and its regulation, we performed a forward genetic screen using a reporter driven by the promoter of Proline Dehydrogenase 1 ( ProDH1 pro :LUC; Shinde et al., 2016) and identified a low water potential stress hypersensitive mutant having a single amino acid change in the Non-Phototrophic Hypocotyl3 (NPH3)-domain of an NRL protein. The hypersensitive phenotype could be alleviated by blocking proline metabolism . The nrl point mutation disrupts NRL interaction with RAB small GTPases which are involved in endo-membrane trafficking. These results have implications for both stress biology and plant signaling. For stress biology, our results show that high levels of proline accumulation often seen during drought have the potential to elicit cell death responses unless specific mechanisms are activated to allow proline to accumulate safely. In terms of signaling, our results indicate that the NPH3 domain has previously unknown functions related to membrane trafficking which will enlighten research on the role of other NPH3 proteins. The plasma membrane-localized Clade E Growth-regulating (EGR) type 2C protein phosphatases and their target protein MASP1 have opposing effects on growth during drought stress (Bhaskara et al., 2017). EGRs and MASP1 have opposing gradients of expression across the root meristem and opposing effects on root meristem size at low water potential. Ectopic MASP1 or EGR expression increased or decreased, respectively, root meristem size and root elongation during low water potential stress. However, ectopic EGR expression had no effect on unstressed plants. Phosphomimic MASP1 could overcome EGR suppression of root meristem size. Together these results indicated that during low water potential leads to EGR activation and attenuation of MASP1 phosphorylation to regulate meristem size and activity (Longkumer et al., 2022). References Bhaskara GB, Wen T-N, Nguyen TT, Verslues PE (2017) Protein Phosphatase 2Cs and Microtubule-Associated Stress Protein 1 control microtubule stability, plant growth, and drought response. Plant Cell 29: 169-191 Longkumer T, Chen C-Y, Biancucci M, Bhaskara GB, Verslues PE (2022) Spatial differences in stoichiometry of EGR phosphatase and Microtubule-Associated Stress Protein 1 control root meristem activity during drought stress. Plant Cell : 34: 742–758 Shinde S, Villamor JG, Lin W-D, Sharma S, Verslues PE (2016) Proline coordination with fatty acid synthesis and redox metabolism of chloroplast and mitochondria. Plant Physiology 172: 1074-1088 . Jozef Schell seminar room Technologiepark 71 - 9052 Invited by Prof Dirk Inzé and Prof Hilde Nelissen If you do not wish to receive this information anymore, please unsubscribe from future mailings at [ https://maillist.psb.ugent.be/mailman/listinfo/seminars | https://maillist.psb.ugent.be/mailman/listinfo/seminars ] Genome editing, cutting-edge technology for a sustainable agriculture VIB-UGent Center for Plant Systems Biology Ghent University Technologiepark-Zwijnaarde 71 9052 Ghent-Belgium Phone: +32(0)9 331 38 00 [ http://www.psb.vib-ugent.be/ | https://www.psb.ugent.be/ ]