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Systemin peptide application improves tomato salt stress tolerance and reveals common adaptation mechanisms to biotic and abiotic stress in plants
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Biostimulant and bioprotective peptides and their use in agriculture
No full textThe present invention relates to novel isolated peptides having biostimulant and bioprotective activity against abiotic and biotic stress in plants, as well as to compositions comprising said peptides. Preferably, the peptides according to the invention are from Solanum lycopersicum (tornato) plants and are produced in a recombinant or synthetic manner. The use of said peptides and/or said composition to increase resistance to biotic and/or abiotic stress in a plant is also described
Peptidi biostimolanti e bioprotettivi e loro impiego in agricoltura
No full textLa presente invenzione si riferisce a nuovi peptidi isolati aventi attività biostimolante e bioprotettiva contro lo stress abiotico e biotico nelle piante, nonché a composizioni comprendenti detti peptidi. Preferibilmente, i peptidi secondo l'invenzione provengono da piante di Solanum lycopersicum (pomodoro) e sono prodotti in modo ricombinante o sintetico. Viene anche descritto l'uso di detti peptidi e/o di detta composizione per aumentare la resistenza a stress biotici e/o abiotici in una pianta
FUNCTIONAL CHARACTERIZATION OF TOMATO PROSYSTEMIN AND PROSYSTEMIN REGIONS: NOVEL TOOLS FOR PLANT DEFENSE
Get PDFProsystemin (ProSys) is a pro-hormone of 200 aminoacidic residues which releases a bioactive peptide hormone of 18 amino acids called Systemin (Sys) involved in the activation of a complex signaling cascade that leads to the production of defense compounds. The tomato genome contains only one copy of Prosys gene; it is composed of 4176 bp and is structured into 11 exons, of which the last one codes for Sys. Sys peptide was traditionally considered as the principal actor that confers protection against both biotic and abiotic environmental challenges observed in tomato plant overexpressing the ProSys. Thus, a single peptide hormone is capable of eliciting multiple defense pathways to counteract a wide range of unfavourable conditions for the plant. So far, it was unknown whether ProSys had any biological function other than being an intermediate in the synthesis of Sys. However, recent evidences suggest that Prosys devoid of the Sys sequence contributes to defense responses. This observation prompted us to investigate the biochemical and structural features of the ProSys protein. To this purpose ProSys has been expressed in BL21 (DE3) E. coli cells and purified. A detailed characterization of this pro-hormone by means of multidisciplinary approach revealed for the first time that this precursor behaves like an intrinsically disordered protein (IDP) possessing intrinsically disordered regions (IDRs) within the sequence.
However, to find out an alternative delivery strategy not relying on transgenic plants, we decided to investigate the effects of exogenous application of the recombinant pro-hormone on the defense responses and its potential use as a plant protection tool in tomato. In particular, plant assays revealed that ProSys direct treatment of leaves is biologically active being very effective in the induction, both locally and systemically, of tomato defense-related genes, conferring protection against different pests.
To our knowledge, this is the first biotic stress related IDP identified in plants, suggesting new interesting insights on the role of IDPs. into plant response against biotic stressors.
IDPs are functionally important proteins lacking a stable or ordered three-dimensional structure. Despite being highly flexible, it has been demonstrated that IDPs have crucial roles in signal transduction process, cell-cycle regulation, gene expression and molecular recognition. The role of IDPs in these processes has been systematically studied in the animal kingdom. In contrast, less reports of these proteins from the plant kingdom are available in the scientific literature. In plant biology, IDPs play crucial roles among plant stress responses, signaling, and molecular recognition pathways, that resemble the functional roles of ProSys in the tomato defense pathways activated upon several biotic and abiotic stresses. These evidences aimed our study focused on the establishment of a relationship between ProSys structure and its biological activity. To this purpose different regions of ProSys have been expressed in BL21 (DE3) E. coli cells, purified and then characterized by a biophysical and biochemical point of view. Results showed that the recombinant fragments are disordered in agreement with what previously shown for the whole precursor. It was subsequently investigated whether the recombinant ProSys Fragments had any biological activity in activating defense responses upon biotic or abiotic attacks. In particular, by using a combination of gene expression analysis and bioassays, we proved that the exogenous supply of the recombinant ProSys Fragments to tomato plants promotes early and late plant defense genes, but only two fragments (namely Fragment I and III, encompassing the N-terminal part of the protein) were found to be the most promising. In addition, it was observed that the latter ones counteracted the development of Spodoptera littoralis larvae and the fungal leaf colonization. These results suggest that the direct application of these recombinant products, which are safe to humans and no-target organisms, may represent an exploitable tool for crop protection
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Colonization of Solanum melongena and Vitis vinifera Plants by Botrytis cinerea Is Strongly Reduced by the Exogenous Application of Tomato Systemin
No full textPlant defense peptides are able to control immune barriers and represent a potential novel resource for crop protection. One of the best-characterized plant peptides is tomato Systemin (Sys) an octadecapeptide synthesized as part of a larger precursor protein. Upon pest attack, Sys interacts with a leucine-rich repeat receptor kinase, systemin receptor SYR, activating a complex intracellular signaling pathway that leads to the wound response. Here, we demonstrated, for the first time, that the direct delivery of the peptide to Solanum melongena and Vitis vinifera plants protects from the agent of Grey mould (Botrytis cinerea). The observed disease tolerance is associated with the increase of total soluble phenolic content, the activation of antioxidant enzymes, and the up-regulation of defense-related genes in plants treated with the peptide. Our results suggest that in treated plants, the biotic defense system is triggered by the Sys signaling pathway as a consequence of Sys interaction with a SYR-like receptor recently found in several plant species, including those under investigation. We propose that this biotechnological use of Sys, promoting defense responses against invaders, represents a useful tool to integrate into pest management programs for the development of novel strategies of crop protection
Prosystemin, a prohormone that modulates plant defense barriers, is an intrinsically disordered protein
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