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Figure S1: Structure and protein sequence analysis of APX family in Ricinus communis (Rc), Manihot esculenta (Me), Jatropha curcas (Jc), Hevea brasiliensis (Hb), Arabidopsis thaliana (At) and Oryza sativa (Os); Figure S2: Sequence logos for the conserved motifs of APX family from Ricinus communis, Arabidopsis thaliana and Oryza sativa; Figure S3: Structure and protein sequence analysis of MDAR family in Ricinus communis (Rc), Manihot esculenta (Me), Jatropha curcas (Jc), Hevea brasiliensis (Hb), Arabidopsis thaliana (At) and Oryza sativa (Os); Figure S4: Sequence logos for the conserved motifs of MDAR from Ricinus communis, Arabidopsis thaliana and Oryza sativa; Figure S5: Structure and protein sequence analysis of DHAR family in Ricinus communis (Rc), Manihot esculenta (Me), Jatropha curcas (Jc), Hevea brasiliensis (Hb), Arabidopsis thaliana (At) and Oryza sativa (Os); Figure S6: Sequence logos for the conserved motifs of DHAR from Ricinus communis, Arabidopsis thaliana and Oryza sativa; Figure S7: Structure and protein sequence analysis of GR family in Ricinus communis (Rc), Manihot esculenta (Me), Jatropha curcas (Jc), Hevea brasiliensis (Hb), Arabidopsis thaliana (At) and Oryza sativa (Os); Figure S8: Sequence logos for the conserved motifs of GR from Ricinus communis, Arabidopsis thaliana and Oryza sativa; Figure S9: Cis-regulatory elements in the APX, MDAR, DHAR, and GR promoter regions from Ricinus communis, Manihot esculenta, Jatropha curcas, and Hevea brasiliensis; Figure S10: miRNA targeting RcAPX, RcMDAR, RcDHAR, and RcGR genes; Table S1: APX, MDAR, DHAR and GR sequences from rice and arabidopsis used as bait to BLASTp analysis; Table S2: Sequences of primers used in RT-qPCR experiments; Table S3: Physicochemical parameters and subcellular predictions from APX in Ricinus communis, Manihot esculenta, Jatropha curcas, Hevea brasiliensis; Table S4: Physicochemical parameters and subcellular predictions from MDAR in Ricinus communis, Manihot esculenta, Jatrop

Ascorbate peroxidase (APX), Monodehydroascorbate Reductase (MDAR), Dehydroascorbate Reductase (DHAR) and Glutathione Reductase (GR) enzymes participate in the ascorbate-glutathione cycle, which exerts a central role in the antioxidant metabolism in plants. Despite the importance of this antioxidant system in different signal transduction networks related to development and response to environmental stresses, the pathway has not yet been comprehensively characterized in many crop plants. Among different eudicotyledons, the Euphorbiaceae family is particularly diverse with some species highly tolerant to drought. Here the APX, MDAR, DHAR, and GR genes in Ricinus communis, Jatropha curcas, Manihot esculenta, and Hevea brasiliensis were identified and characterized. The comprehensive phylogenetic and genomic analyses allowed the classification of the genes into different classes, equivalent to cytosolic, peroxisomal, chloroplastic, and mitochondrial enzymes, and revealed the duplication events that contribute to the expansion of these families within plant genomes. Due to the high drought stress tolerance of Ricinus communis, the expression patterns of ascorbate-glutathione cycle genes in response to drought were also analyzed in leaves and roots, indicating a differential expression during the stress. Altogether, these data contributed to the characterization of the expression pattern and evolutionary analysis of these genes, filling the gap in the proposed functions of core components of the antioxidant mechanism during stress response in an economically relevant group of plants., [Simple Summary] The climatic changes pose important threats to agriculture. Plants are sessile organisms and need to cope with different environmental conditions throughout their lifespan. Most responses involve different signaling molecules, including reactive oxygen species (ROS). Due to their high reactivity, ROS are also an oxidative threat to the cell. Consequently, plant cells display elaborated defenses against oxidative stress. The ascorbate-glutathione cycle is the main antioxidant pathway in photosynthetic organisms and is composed by the enzymes ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR). Here, the APX, MDAR, DHAR and GR genes from castor bean, cassava, jatropha and rubber tree were identified and classified. This classification allowed the prediction of their subcellular localization within plant cells, such as cytosol, peroxisomes, chloroplasts, and mitochondria. Our analysis also contributes to understanding the evolutionary history of these genes. The expression pattern of ascorbate-glutathione cycle genes in castor bean submitted to drought reveals changes in leaves and roots. Altogether, these data contribute to uncovering the regulation of ROS metabolism during stress response in castor bean, which is highly tolerant to drought.

A doença azul (DA) do algodoeiro é uma doença importante do algodão do cerrado brasileiro, acarretando grandes perdas econômicas. Trata-se de uma virose associada ao polerovirus Cotton leafroll dwarf virus (CLRDV) e transmitida pelo pulgão Aphis gossypii, de forma persistente e circulativa. Em função da relevância da doença, a partir do final da década de 90, variedades suscetíveis passaram a ser substiudas por variedades resistentes a DA. Entretanto, a partir da safra 2006, relatos de campos de variedades resistentes onde algumas plantas apresentavam sintomas da DA passaram a ocorrer. Nos dois anos ocnsecutivos a ocorrência de tais eventos sofreu um espalhamento e na última safra, ocorreram eventos em São Paulo, Minas Gerais, Mato Grosso e Góias. Neste trabalho foram analisadas plantas de quatro variedades resistentes distintas (BRS Cedro, Delta Opal, CD406 e FMT701), coletadas em campos de algodão dos estados de Goiás e Mato Grosso. O diagnóstico molecular positivo para infecção do CLRDV foi observado em todas as amostras analisadas, indicando a ocorrência de quebra de resistência em quatro variedades. resistentes a doença azul. Análises dos fragmentos virais amplificados sugerem que duas substituições na proteína do movimento podem estar associadas ao fenômeno de quebra de resistência pelo CLRDV. (Réseau d'auteur)

Here we describe the developing of molecular diagnose assays for Cotton blue disease. Previously we sequenced part of the genome of its casual agent Based in alignment analysis of this sequence we designed oligonucleotids pairs that specifically will amplify this virus in infected plants. We tested these pairs of primers in two independent infected plants, a lot coming from Mato Grosso and another lot from Paraná, both of them infected with the same virus isolate. The results obtained showed that the primers were able to amplify virus specific bands in a robust and reproductively manner. Besides the development of this RT-PCR based method we also developed a northern blot assay for this disease using virus CP as probe. Using one or both methods it is now possible to identify precociously Cotton blue disease in fields conditions what may reduce importantly the lost associated with the dissemination of this important disease in Brazilian and others producer countries fields.