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Introduction: The Family of pathogenesis-related proteins 10 (PR-10) is widely distributed in the plant kingdom. PR-10 are multifunctional proteins, constitutively expressed in all plant tissues, playing a role in growth and development or being induced in stress situations. Several studies have investigated the preponderant role of PR-10 in plant defense against biotic stresses; however, little is known about the mechanisms of action of these proteins. This is the first systematic review conducted to gather information on the subject and to reveal the possible mechanisms of action that PR-10 perform. Methods: Therefore, three databases were used for the article search: PubMed, Web of Science, and Scopus. To avoid bias, a protocol with inclusion and exclusion criteria was prepared. In total, 216 articles related to the proposed objective of this study were selected. Results: The participation of PR-10 was revealed in the plant's defense against several stressor agents such as viruses, bacteria, fungi, oomycetes, nematodes and insects, and studies involving fungi and bacteria were predominant in the selected articles. Studies with combined techniques showed a compilation of relevant information about PR-10 in biotic stress that collaborate with the understanding of the mechanisms of action of these molecules. The up-regulation of PR-10 was predominant under different conditions of biotic stress, in addition to being more expressive in resistant varieties both at the transcriptional and translational level. Discussion: Biological models that have been proposed reveal an intrinsic network of molecular interactions involving the modes of action of PR-10. These include hormonal pathways, transcription factors, physical interactions with effector proteins or pattern recognition receptors and other molecules involved with the plant's defense system. Conclusion: The molecular networks involving PR-10 reveal how the plant's defense response is mediated, either to trigger susceptibility or, based on data systematized in this review, more frequently, to have plant resistance to the disease.

International audience; The cosmetic and fragrance industry largely exploits citrus essential oils (EOs) because of their aromatic properties. EO compositions are complex and differ between fruit pericarp (PEO) and leaf (LEO). Citrus fruit grow in many countries under very different climates. Seventeen citrus cultivars were selected and their similarities between the two collections were verified by SSR (Single Sequence Repeat) and InDel (Insertion and Deletion) markers to assess the effects of the environment and cultivation practices on the EO yield and composition. LEOs and PEOs were extracted by water distillation and analyzed by GC-MS. PEO yields were generally higher in Corsica than in Bahia, especially in the citron family. PEOs in this family were richer in limonene in Bahia than in Corsica while, conversely, neral, geranial and derivatives were present in a higher proportion in Corsican varieties. A few minor components were site-specific, such as nookaton, a pummelo-specific compound that was not present in grapefruit cultivated in Bahia. If climate change over the last 20 years has not affected the PEO composition in Corsica, the contrasted environmental conditions and cultural practices between Bahia and Corsica could possibly explain the EO variations.

Table S3. Repeat elements in the genomes. (DOCX 14 kb)

Glutathione peroxidases (GPXs) are enzymes which are part of the antioxidant system of the cell. Mammalian GPXs are known as selenoproteins because containing the selenocysteine (Sec) amino acid. In plants, these proteins are less known. Here, were analyzed the protein structure and the gene expression of five GPXs from Theobroma cacao . The three-dimensional structure of the TcGPXs showed that the catalytic site of Tc PHGPX and TcGPX ( 2,4 and 5) contain a cysteine while the GPX8 contain a tryptophan. Interestingly, the T. cacao GPX did not show any selenocysteine in their structure. Docking analysis revealed that TcGPXs can bind to selenium. Phylogenetic analysis split plant and mammalian GPXs in two distinct branches. RT-qPCR analysis of TcGPXs during the T. cacao - Moniliophthora perniciosa interaction showed that TcGPX8 gene is overexpressed in the green broom phase of the susceptible cacao variety. In the resistant variety, the TcGPX5 was significantly more expressed in the final stages of the interaction. This study shows that TcGPXs are important targets for the understanding of the T. cacao - M. perniciosa interaction but also for the functionality of these proteins.

Pathogenesis related-proteins 10 (PR-10) have ribonuclease and antifungal activity. A PR-10 from Theobroma cacao ( TcPR-10 ) identified in a cDNA library from the cacao- Moniliophthora perniciosa interaction showed antifungal activity against M. perniciosa and Saccharomyces cerevisiae , and the TcPR-10 was internalized by both organisms. Previous studies indicated that the antifungal activity and internalization of TcPR-10 appears to be related to Snq2 membrane permeates and transporters. In order to investigate the antifungal action of TcPR-10 and its internalization in fungal cells, molecular docking was performed to check the interaction between the ABC (Snq2) transporter and TcPR-10 mut, recombinant mutant protein with reduced allergenicity potential. The three-dimensional structure of TcPR-10 mut and Snq2 were modelled and used in molecular docking analysis using the ClusPro online toolkit. Snq2 interacted with TcPR-10 mut in its transmembrane domain, suggesting the internalization of this protein by means of this transporter, similarly to the transport of alkaloids.

Table S2. Assessment of genome quality by BUSCO. (DOCX 12 kb)

Scion/rootstock interaction is important for plant development and for breeding programs. In this context, polyploid rootstocks presented several advantages, mainly in relation abiotic stresses. Here we analyzed the response to drought of two different scion/rootstock combinations presenting different polyploidy: the diploid (2x) and autotetraploid (4x) Rangpur lime rootstocks grafted with 2x Valencia Delta sweet orange scions (V/2xRL and V/4xRL). We developed an interactomic approach to identify proteins involved in V/2xRL and V/4xRL response to drought. A main interactomic network was built from V/2xRL and V/4xRL data. Exclusive proteins of the V/2xRL and V/4xRL networks, as well as common to both networks were identified. Functional clusters were obtained and two models of drought stress response were designed. Even if the V/2xRL plant implement some tolerance mechanisms, the global plant response to drought was rapid and quickly exhaustive resulting in a general tendency to dehydration avoidance, which presented some advantage in short and strong drought stress conditions. At the contrary, the V/4xRL plants presented a response which strong impacts on development but that present some advantages in case of prolonged drought. Finally, some specific central proteins were identified as good candidates for subsequent functional analysis of citrus genes related to drought response.

The alternative oxidase (AOX) protein is present in plants, fungi and some invertebrates. It is involved in the mitochondrial respiratory chain, providing an alternative route for the transport of electrons, leading to the reduction of oxygen to form water. The present study aimed to characterize the family of AOX genes in mandarin and sweet orange. Four AOX genes were identified in each citrus species. The 1500 bp-upstream region of each AOX gene contained regulatory cis-elements related to internal and external response factors. CsAOX genes showed a differential expression in citrus tissues. AOX proteins contained conserved motifs as well as several putative post-translational modification sites. The CcAOXd protein was modeled by homology and its 3-D structure showed two hydrophobic helices probably involved in the anchoring in the inner mitochondrial membrane. The active site of the protein is located in a hydrophobic environment deep inside the AOX structure and contains a diiron center. The molecular docking of CcAOXd with ubiquinone showed that the binding site is a recessed pocket formed by the helices and submerged in the membrane. These data are important for future functional studies of citrus AOX, as well as for biotechnological approaches leading to AOX inhibition using ubiquinone homologs.