WORKSHOP: New Frontiers in Plant Biology

Session on “Plant Development” – Chair: Mónica Pernas

Dr. Crisanto Gutiérrez, from the CBM-“SO”CSIC, described his group’s recent advances in plant cell proliferation and development, and the relevance of the “chromatin context” in the regulation of these processes. This context determines DNA replication and cell division.  Dr. Arp Schnittger, from University of Hamburg, dealt with the “mysteries of meiosis”, an essential genetic mechanism poorly understood in plants. His group has identified several key regulatory components, which determine the processes of entry into germ line, and that might be relevant to understand unequal DNA recombination during plant meiosis, a bottle neck in crop breeding. Dr. Siobhan Brady, from University of California at
Davis, described novel functions of the PRC2 complex, which regulates transcriptional gene silencing. Among these functions is the modulation of different plant developmental processes, such as vascular tissue formation. Her group has identified a set of transcriptional factors which regulate the expression of PRC2, thus providing an additional level of transcriptional expression regulation. Dr. Doris Wagner, from the University of Pennsylvania at Philadelphia, described the emerging roles of the phytohormones gibberelic acid (GA) and auxins in the control of flowering and the impact of these regulatory processes in crop yield. Her group has characterized several key regulators, such as BRM protein, which contributes to plant resistance to abiotic stresses by modulating Abscisic Acid (ABA) signaling pathway.

Session on “Interactions of Plants with the Environment” – Chairs: Emilia López-Solanilla and Fernando García-Arenal

Dr. Shen-Yang He, from Michigan State University at East Lansing, remarked the relevance of the study of the three components of the biotic triangle (plant-microbes-environment) to fully understand plant response to pathogens and beneficial microorganisms. He presented the results obtained by his group using the “FlowPot” equipment that allows to grow plants in soil under axenic (microorganism free) and holoxenic (re-inoculated with soil microorganisms) conditions. These analyses showed that soil microorganisms contribute to plant immunocompetence, like in animals, since axenic grown plants were highly susceptible to pathogens. Dr. Maria Harrison, from Cornell University at Ithaca, dealt with the role of GA, the GA regulatory DELLA proteins, and soil inorganic phosphate in the regulation of plant colonization by arburscular mycorrhiza. She introduced the concept of ‘genome waiting’: getting more sequenced plant genomes will provide essential information to identify the conserved (master) genes in the mycorrhization process, like RAD1, a key regulatory plant phosphatase. Dr. Roberto Solano, from the CNB-CSIC, presented the most recent advances of his group in the characterization of jasmonic acid (JA) signalling in the Marchantia plant, a really simple genome plant that provides a perfect biosystem to understand and characterize the evolutionary essential elements of some signaling pathways, like JA’s. Solano´s group data point to the conservation of the JA pathway components in Marchantia, although JA hormone does not seem to be synthesized in this plant: “JA pathways without JA”. Dr. Stephan Blanc, from the INRA-CNRS at Montpellier, described the paradox of multipartite plant viruses that do not fulfil well-established virological principles. He showed, through a set of very well defined experiments, how nanoviruses can establish successful systemic infections in whole plants, yet replicating only parts of the complete viral genome in each individual cell. This finding adds an additional level of complexity in the evolution of viral genome replication. Carmen Castresana, from the CNB-CSIC, showed the most recent advances of her group in the characterization of the role of oxylipins in the regulation of plant innate immunity. Castresana´s group has identified a vast collection of Arabidopsis mutants (noxy) not responding to oxylipins. The characterization of some of these mutants revealed the relevance of mitochondria and cell wall integrity in oxlypins-mediated regulation of plant immune responses. Karin Krupinska, from University of Kiel, described the novel function of the WHIRLY proteins in plants. This group of DNA/RNA binding proteins regulates the accumulation of some particular group of miRNAs, which impact on several biological processes. Michael Feldbrügge, from Heinrich-Heine-University at Düsseldorf, described a novel mechanism of local translation of mRNAs in the endosome of Ustilago maydis, a corn pathogen. He demonstrated that this molecular mechanism could have a relevant biotechnological application since it could be used to produce and secrete heterologous proteins, such as chitinases or surfactant proteins. In the last talk of this session, Holger Putchka, from Botanic Institute II at Karlsruhe, described the emerging DNA editing technologies, including CRISPR/Cas9, and the almost unlimited potential to generate novel mutations and further genetic applications. His talk was a good example of the New Frontiers in Plant Biology and the impact of these novel technologies in crop breeding.

Session on “Systems and Synthetic Biology” – Chair: Fernando Ponz

Chris Voigt, Co-Director of the Synthetic Biology Center at the MIT, talked about applications of synthetic biology in agriculture. In particular, the refactoring of nitrogen fixation gene clusters and their wide transfer to a variety of ecologically important microorganisms. Yuri Gleba, CEO of the biotech companies Icon Genetics and Nomad Bioscience, explained how these companies are exploiting the potential of their proprietary virus-based technologies for transient expression in plants (molecular farming) to get into new biotechnological markets, ranging from biomedicine to food science, including several others. Paulo Arruda, from the University of Campinas, presented the first in-depth description of the sugarcane microbiome, a work that he is carrying out in collaboration with CBGP scientists. Sugarcane presents a very rich and complex microbiome characterized by a surprising abundance of fungi, notably yeasts. On the bacterial side, many of the previously isolated sugarcane endophytes turned out, notably, to be minor microbiome components, while many of its main components have yet to be characterized. Gabino Sánchez, from the Plant Research International at Wageningen University, introduced the concept of “reduced genome waiting” and the relevance of getting well-sequenced genomes to speed up the R&D programs in the public and enterprise labs. He presented the most recent advances and technologies (e.g. optical mapping) that can be applied to genome assembly and their impact in crop breeding and germoplasm resources characterization. He also showed examples of cross-sector opportunities to translate computational and technical advances from the medical sector to the agrofood sector.