DSpace Angular :: Browsing by Author "Arce-Johnson, Patricio"

Browsing by Author "Arce-Johnson, Patricio"

Now showing 1 - 14 of 14

Autopolyploidization and in vitro regeneration of three highbush blueberry (Vaccinium corymbosum L.) cultivars from leaves and microstems
(SPRINGER, 2024) Jarpa-Tauler, Gabriela; Martinez-Barradas, Vera; Romero-Romero, Jesus Lucina; Arce-Johnson, Patricio
Blueberries are a fruit with an increasing global demand due to their phytochemical and bioactive compounds content. They are promoted worldwide because of their health benefits. For optimal growth and productivity, blueberry crops need acidic soil pH, specific chilling hours, and an adequate atmospheric temperature. This delicate production equilibrium is under severe threat from climate change, potentially leading to reduced yields and increased cultivation costs unless new cultivars are developed for each edafoclimatic zone. Therefore, considering varietal replacements with more productive cultivars offering higher quality and better adaptability to local conditions is imperative. In this study, we employ polyploidization and in vitro tissue culture to promote variability and lay the foundation for new cultivar development. We report the successful induction of octoploids in three blueberry cultivars, namely 'Biloxi', 'Legacy', and 'Duke', through whole-genome duplication. Leaves and microstem explants were exposed to 0.1% colchicine for 24 and 48 hours in in vitro culture. After analyzing the polyploid level of 160 regenerated shoots using DNA flow cytometry, we obtained a total of 18 mutants, consisting of 8 mixoploids and 10 octoploids. The number of chloroplasts in the stomata was analyzed by fluorescence microscopy, revealing the duplication of these organelles in the induced octoploid plants. To our knowledge, this represents the first successful induction of octoploids in three blueberry cultivars -'Biloxi,' 'Legacy,' and 'Duke'- achieved by exposing leaves and microstem explants to colchicine in in vitro culture. This technique holds promise as a valuable tool for the development of improved blueberry cultivars.
Biochemical and molecular changes in response to aluminium-stress in highbush blueberry (Vaccinium corymbosum L.)
(2011) Inostroza-Blancheteau, Claudio; Reyes-Diaz, Marjorie; Aquea, Felipe; Nunes-Nesi, Adriano; Alberdi, Miren; Arce-Johnson, Patricio
Aluminium (Al) stress is an important factor limiting crop yields in acid soils. Despite this, very little is known about the mechanisms of resistance to this stress in woody plants. To understand the mechanisms of Al-toxicity and response in blueberries, we compared the impact of AI-stress in Al-resistant and AI-sensitive genotypes using Vaccinium corymbosum L. (Ericaceae) as a plant model. We investigated the effect of Al-stress on the physiological performance, oxidative metabolism and expression of genes that encode antioxidant enzymes in two V. corymbosum cultivars maintained hydroponically with AlCl3 (0 and 100 mu M). Microscopic analyses of AI-treated root tips suggested a higher degree of Al-induced morphological injury in Bluegold (sensitive genotype) compared to Brigitta (resistant genotype). Furthermore, the results indicated that Brigitta had a greater ability to control oxidative stress under Al-toxicity, as reflected by enhancement of several antioxidative and physiological properties (radical scavenging activity: RSA, superoxide dismutase: SOD and catalase: CAT; maximum quantum yield: Fv/Fm, effective quantum yield: 04)511, electron transport rate: ETR and non-photochemical quenching: NPQ). Finally, we analyzed the expression of genes homologous to GST and ALDH, which were identified in a global expression analysis. In the resistant genotype, the expression of these genes in response to Al-stress was greater in leaves than in roots. (C) 2011 Elsevier Masson SAS. All rights reserved.
Characterization of Endogenous Levels of Brassinosteroids and Related Genes in Grapevines
(2022) Parada, Francisca; Oklestkova, Jana; Arce-Johnson, Patricio
Agronomic breeding practices for grapevines (Vitis vinifera L.) include the application of growth regulators in the field. Brassinosteroids (BRs) are a family of sterol-derived plant hormones that regulate several physiological processes and responses to biotic and abiotic stress. In grapevine berries, the production of biologically active BRs, castasterone and 6-deoxocastasterone, has been reported. In this work, key BR genes were identified, and their expression profiles were determined in grapevine. Bioinformatic homology analyses of the Arabidopsis genome found 14 genes associated with biosynthetic, perception and signaling pathways, suggesting a partial conservation of these pathways between the two species. The tissue- and development-specific expression profiles of these genes were determined by qRT-PCR in nine different grapevine tissues. Using UHPLC-MS/MS, 10 different BR compounds were pinpointed and quantified in 20 different tissues, each presenting specific accumulation patterns. Although, in general, the expression profile of the biosynthesis pathway genes of BRs did not directly correlate with the accumulation of metabolites, this could reflect the complexity of the BR biosynthesis pathway and its regulation. The development of this work thus generates a contribution to our knowledge about the presence, and diversity of BRs in grapevines.
Characterization of physiological and antioxidant responses in Run1Ren1 Vitis vinifera plants during Erysiphe necator attack
(2022) Sosa-Zuniga, Viviana; Martinez-Barradas, Vera; Espinoza, Carmen; Tighe-Neira, Ricardo; Vidal Valenzuela, Alvaro; Inostroza-Blancheteau, Claudio; Arce-Johnson, Patricio
Grapevine is a fruit crop of major significance worldwide. Fungal attacks are one of the most relevant factors affecting grapevine yield and fruit quality, and powdery mildew caused by Erysiphe necator is one of the most harmful fungal diseases for this fruit-bearing species. Incorporating resistance genes such as Run1 and Ren1 in new vine selections offers a sustainable alternative to control the disease. These combined loci produce an immune response that prevents the development of the disease. However, to date studies are lacking concerning whether this response generates alterations in the physiological and antioxidant parameters of resistant plants in the presence of the fungus or if it has an associated energy cost. Therefore, the main goal of our research was to determine if Run1Ren1 plants present alterations in their physiological and biochemical parameters in the presence of the fungus. To achieve this target, a previously characterized resistant Run1Ren1 genotype and the susceptible Carmenere cultivar were analyzed. We evaluated photochemical parameters (Fv'/Fm', phi PSII and ETR), net photosynthesis (Pn), photosynthetic pigments, transpiration (E), stomatal conductance (g(s)), oxidative stress parameters (MDA), antioxidant activity, and phenols. Our results show that the physiological parameters of Run1Ren1 plants were not negatively affected by the fungus at 10 days post-inoculation, contrasting with alterations observed in the susceptible plants. Therefore, we propose that the resistance response triggered by Run1Ren1 is physiologically and biochemically advantageous to grapevines by preventing the development of powdery mildew infection.
Drought Tolerance Evaluation of 'Zorzal,' the Most Cultivated Common Bean in Chile, a Country Facing Desertification
(2024) Martinez-Barradas, Vera; Inostroza-Blancheteau, Claudio; Tighe-Neira, Ricardo; Romero-Romero, Jesus Lucina; Schwember, Andres R.; Arce-Johnson, Patricio
During the last decades, water distribution around the globe has been affected by climate change. Particularly, in Chile, the last decade has been marked by a mega-drought period, which has severely impacted agriculture. In this scenario, common bean (Phaseolus vulgaris L.) has been seriously affected due to its dependence on irrigation. In this work, we studied how 'Zorzal,' the most sown cultivar in Chile copes with drought stress and the mechanisms used to deal with it. A greenhouse experiment was performed during the 2019-2020 growing season. Plants were subjected to a severe drought stress suspending irrigation at the pre-flowering stage. Photosynthetic parameters, chlorophyll concentration, relative leaf water content (RWC) and lipid peroxidation were analyzed at 7 and 21 days after water suspension, yield was analyzed at the end of the growing season, and those parameters were compared to a susceptible cultivar of the same gene pool 'Arroz Tuscola.' 'Zorzal' stood out for having diverse treats associated with drought tolerance, as maintaining stable RWC during drought stress, a better reactive oxygen species scavenging system than 'Arroz Tuscola,' and stable root biomass during the drought condition. However, seed production was significantly reduced. Our results evidence that 'Zorzal,' the most widely cultivated cultivar of common bean in Chile, has good physiological and anatomical treats for plant survivance under drought stress conditions. However, our study suggests that these characteristics may not be enough to maintain a stable seed production.
Expression of the crucifer-infecting TMV-Cg movement protein in tobacco plants complements in trans a TMV-U1 trafficking-deficient mutant
(2006) Diaz-Griffero, Felipe; Cancino, Carmen Espinoza; Arevalo, Consuelo Medina; Arce-Johnson, Patricio
Tobamovirus movement proteins play a determinant role in the establishment of infections in plants. allowing the local movement of viral RNA genome through plasmodesmatas. We expressed the movement protein (MP) of the crucifer- and garlic-infecting Tobacco Mosaic Virus strain Cg (TMV-Cg) in both resistant Xanthi NN and sensitive Xanthi nn Nicotiana tabacum plants. MP-Q function was assayed by inoculating transgenic plants with a trafficking-deficient mutant of TMV strain U1. Following infection,. local necrotic lesions were developed in resistant transgenic plants. and a systemic infection was produced in sensitive tobaccos. Thus, movement function of the mutant virus was complemented in trans by MP-Cg expressed in transgenic plants. causing the same symptoms as wild-type strain. We demonstrated that the function of MP-U1 could be replaced efficiently by MP-Cg. even though these proteins share only 36% of identity. Similar hydrophobic patterns of MP-Cg and MP-U1 suggests structure and function conservations of both proteins. This work is an example of how two tobamoviruses differing in their host range help to understand viral movement mechanism during the infection.
Functional characterization of Citrus macrophylla BOR1 as a boron transporter
(2013) Canon, Paola; Aquea, Felipe; Rodriguez-Hoces de la Guardia, Amparo; Arce-Johnson, Patricio
Plants have evolved to develop an efficient system of boron uptake and transport using a range of efflux carriers named BOR proteins. In this work we isolated and characterized a boron transporter of citrus (Citrus macrophylla), which was named CmBOR1 for its high homology to AtBOR1. CmBOR1 has 4403bp and 12 exons. Its coding region has 2145bp and encodes for a protein of 714 amino acids. CmBOR1 possesses the molecular features of BORs such as an anion exchanger domain and the presence of 10 transmembrane domains. Functional analysis in yeast indicated that CmBOR1 has an efflux boron transporter activity, and transformants have increased tolerance to excess boron. CmBOR1 is expressed in leaves, stem and flowers and shows the greatest accumulation in roots. The transcript accumulation was significantly increased under boron deficiency conditions in shoots. In contrast, the accumulation of the transcript did not change in boron toxicity conditions. Finally, we observed that constitutive expression of CmBOR1 was able to increase tolerance to boron deficiency conditions in Arabidopsis thaliana, suggesting that CmBOR1 is a xylem loading boron transporter. Based on these results, it was determined that CmBOR1 encodes a boric acid/borate transporter involved in tolerance to boron deficiency in plants.
Identification of genes expressed during early somatic embryogenesis in Pinus radiata
(2008) Aquea, Felipe; Arce-Johnson, Patricio
Analysis of cDNA-AFLPs was used to study gene expression underlying the early embryogenic process in the gymnosperm Pinus radiata. Somatic embryogenesis in this species was used as a model as it resulted in the generation of a large number of embryos at defined stages of development. The gene expression patterns of three ernbryogenic stages were compared with non-embryogenic cells. Fifty transcript-derived fragments (TDFs) that are upregulated and 32 TDFs that are down-regulated in the embryogenic stages were selected, sequenced and their homologies sought in the databases. Expression of a selected subset of differentially expressed genes was confirmed by RT-PCR and their levels of expression were quantified. Of the 50 up-regulated TDFs, 16 are homologous to genes encoding either known or putative proteins in higher plants, 19 are homologous to conifer ESTs and 15 did not show significant matches. Of the down-regulated TDFs, 8 are homologous to genes encoding either known or putative proteins, 20 are homologous to conifer ESTs and 4 of them did not show significant matches in DNA or protein sequence database. The known up-regulated genes were similar to genes involved in cellular metabolism and in the stress response and the known down-regulated genes were similar to genes involved in proteolysis, cell wall modification and signaling pathways. Their putative individual function is briefly reviewed based on published information, and the potential roles of these genes in embryo development are discussed. (C) 2008 Elsevier Masson SAS. All rights reserved.
Isolation of the three grape sub-lineages of B-class MADS-box TM6, PISTILLATA and APETALA3 genes which are differentially expressed during flower and fruit development
(2007) Poupin, Maria Josefina; Federici, Fernan; Medina, Consuelo; Matus, Jose Tomas; Timmermann, Tania; Arce-Johnson, Patricio
The B class of MADS-box floral homeotic genes specifies petal and stamen identity in angiosperms. While this group is one of the most studied in herbaceous plant species, it has remained largely uncharacterized in woody species such as grapevine. Although the B class PI/GLO and AP3/DEF clades have been extensively characterized in model species, the role of the TM6 subgroup within the AP3 clade is not completely understood, since it is absent in Arabidopsis thaliana. In this study, the coding regions of VvTM6 and VvAP3 and the genomic sequence of VvPI, were cloned. VvPI and AtPI were confirmed to be functional homologues by means of complementation of the pi Arabidopsis mutant. Expression analysis revealed that VvPI and VvAP3 transcripts are restricted almost exclusively to inflorescences, although VvPI was detected at low levels in leaves and roots. VvTM6 expresses throughout the plant, with higher levels in flowers and berries. A detailed chronological study of grape flower progression by light microscopy and temporal expression analysis throughout early and late developmental stages, revealed that VvPI expression increases during pollen maturation and decreases between the events of pollination and fertilization, before the cap fall. On the other hand, VvTM6 is expressed in the last stage of anther development. Specific expression of VvAP3 and VvPI was detected in petals and stamens within the flower, while VvTM6 was also expressed in carpels. Moreover, this work provides the first evidence for expression of a TM6-like gene throughout fruit growth and ripening. Even if these genes belong to the same genetic class they could act in different periods and/or tissues during reproductive organ development. (C) 2007 Elsevier B.V. All rights reserved.
MYB24 orchestrates terpene and flavonol metabolism as light responses to anthocyanin depletion in variegated grape berries
(2023) Zhang, Chen; Dai, Zhanwu; Ferrier, Thilia; Orduna, Luis; Santiago, Antonio; Peris, Arnau; Wong, Darren C. J.; Kappel, Christian; Savoi, Stefania; Loyola Muñoz, Rodrigo Esteban; Amato, Alessandra; Kozak, Bartosz; Li, Miaomiao; Liang, Akun; Carrasco, David; Meyer Regueiro, Carlos José; Espinoza, Carmen; Hilbert, Ghislaine; Figueroa-Balderas, Rosa; Cantu, Dario; Arroyo-Garcia, Rosa; Arce-Johnson, Patricio; Claudel, Patricia; Errandonea, Daniel; Rodriguez-Concepcion, Manuel; Duchene, Eric; Huang, Shao-Shan Carol; Castellarin, Simone Diego; Tornielli, Giovanni Battista; Barrieu, Francois; Matus, Jose Tomas
Variegation is a rare type of mosaicism not fully studied in plants, especially fruits. We examined red and white sections of grape (Vitis vinifera cv. 'Bequignol') variegated berries and found that accumulation of products from branches of the phenylpropanoid and isoprenoid pathways showed an opposite tendency. Light-responsive flavonol and monoterpene levels increased in anthocyanin-depleted areas in correlation with increasing MYB24 expression. Cistrome analysis suggested that MYB24 binds to the promoters of 22 terpene synthase (TPS) genes, as well as 32 photosynthesis/light-related genes, including carotenoid pathway members, the flavonol regulator HY5 HOMOLOGUE (HYH), and other radiation response genes. Indeed, TPS35, TPS09, the carotenoid isomerase gene CRTISO2, and HYH were activated in the presence of MYB24 and MYC2. We suggest that MYB24 modulates ultraviolet and high-intensity visible light stress responses that include terpene and flavonol synthesis and potentially affects carotenoids. The MYB24 regulatory network is developmentally triggered after the onset of berry ripening, while the absence of anthocyanin sunscreens accelerates its activation, likely in a dose-dependent manner due to increased radiation exposure. Anthocyanins and flavonols in variegated berry skins act as effective sunscreens but for different wavelength ranges. The expression patterns of stress marker genes in red and white sections of 'Bequignol' berries strongly suggest that MYB24 promotes light stress amelioration but only partly succeeds during late ripening., MYB24 controls metabolic responses in skin sections of variegated grape berries lacking anthocyanin to cope with high-intensity and UV light stress, promoting terpene and flavonol accumulation.
Powdery Mildew Resistance Genes in Vines: An Opportunity to Achieve a More Sustainable Viticulture
(2022) Sosa Zúñiga, Viviana; Vidal Valenzuela, Álvaro; Barba, Paola; Espinoza Cancino, Carmen; Romero-Romero, Jesús; Arce-Johnson, Patricio
Grapevine (Vitis vinifera) is one of the main fruit crops worldwide. In 2020, the total surface area planted with vines was estimated at 7.3 million hectares. Diverse pathogens affect grapevine yield, fruit, and wine quality of which powdery mildew is the most important disease prior to harvest. Its causal agent is the biotrophic fungus Erysiphe necator, which generates a decrease in cluster weight, delays fruit ripening, and reduces photosynthetic and transpiration rates. In addition, powdery mildew induces metabolic reprogramming in its host, affecting primary metabolism. Most commercial grapevine cultivars are highly susceptible to powdery mildew; consequently, large quantities of fungicide are applied during the productive season. However, pesticides are associated with health problems, negative environmental impacts, and high costs for farmers. In paralleled, consumers are demanding more sustainable practices during food production. Therefore, new grapevine cultivars with genetic resistance to powdery mildew are needed for sustainable viticulture, while maintaining yield, fruit, and wine quality. Two main gene families confer resistance to powdery mildew in the Vitaceae, Run (Resistance to Uncinula necator) and Ren (Resistance to Erysiphe necator). This article reviews the powdery mildew resistance genes and loci and their use in grapevine breeding programs.
Synthetic seed production from somatic embryos of Pinus radiata
(2008) Aquea, Felipe; Poupin, Maria Josefina; Matus, Jose Tomas; Gebauer, Marlene; Medina, Consuelo; Arce-Johnson, Patricio
Pinus radiata is one of the most important forestry species in the southern hemisphere. This work describes the regeneration of this plant via somatic embryogenesis from immature zygotic embryos. To improve this process, somatic embryogenic cell suspensions were established in liquid media for the generation of material for embryo maturation. Each developmental stage of these suspensions was characterized by microscopy and their growth phases quantified. An alginate-containing medium was used as an encapsulation method for the somatic embryos that were then germinated as artificial seeds in vitro. The protocols described in this work are both useful and reliable for industrial purposes.
The photomorphogenic factors UV-B RECEPTOR 1, ELONGATED HYPOCOTYL 5, and HY5 HOMOLOGUE are part of the UV-B signalling pathway in grapevine and mediate flavonol accumulation in response to the environment
(2016) Loyola, Rodrigo; Herrera, Daniela; Mas, Abraham; Wong, Darren Chern Jan; Hoell, Janine; Cavallini, Erika; Amato, Alessandra; Azuma, Akifumi; Ziegler, Tobias; Aquea, Felipe; Castellarin, Simone Diego; Bogs, Jochen; Tornielli, Giovanni Battista; Pena-Neira, Alvaro; Czemmel, Stefan; Antonio Alcalde, Jose; Tomas Matus, Jose; Arce-Johnson, Patricio
By performing molecular studies coupled to radiation experiments and in silico systems analyses, we have ascertained the role of the grapevine UV-B receptor and two HY5 homologues in regulating flavonol synthesis.Grapevine (Vitis vinifera L.) is a species well known for its adaptation to radiation. However, photomorphogenic factors related to UV-B responses have not been molecularly characterized. We cloned and studied the role of UV-B RECEPTOR (UVR1), ELONGATED HYPOCOTYL 5 (HY5), and HY5 HOMOLOGUE (HYH) from V. vinifera. We performed gene functional characterizations, generated co-expression networks, and tested them in different environmental conditions. These genes complemented the Arabidopsis uvr8 and hy5 mutants in morphological and secondary metabolic responses to radiation. We combined microarray and RNA sequencing (RNA-seq) data with promoter inspections to identify HY5 and HYH putative target genes and their DNA binding preferences. Despite sharing a large set of common co-expressed genes, we found different hierarchies for HY5 and HYH depending on the organ and stress condition, reflecting both co-operative and partially redundant roles. New candidate UV-B gene markers were supported by the presence of HY5-binding sites. These included a set of flavonol-related genes that were up-regulated in a HY5 transient expression assay. We irradiated in vitro plantlets and fruits from old potted vines with high and low UV-B exposures and followed the accumulation of flavonols and changes in gene expression in comparison with non-irradiated conditions. UVR1, HY5, and HYH expression varied with organ, developmental stage, and type of radiation. Surprisingly, UVR1 expression was modulated by shading and temperature in berries, but not by UV-B radiation. We propose that the UV-B response machinery favours berry flavonol accumulation through the activation of HY5 and HYH at different developmental stages at both high and low UV-B exposures.
The role of auxin during early berry development in grapevine as revealed by transcript profiling from pollination to fruit set
(2021) Godoy, Francisca; Kuhn, Nathalie; Munoz, Mindy; Marchandon, German; Gouthu, Satyanarayana; Deluc, Laurent; Delrot, Serge; Lauvergeat, Virginie; Arce-Johnson, Patricio
Auxin is a key phytohormone that modulates fruit formation in many fleshy fruits through the regulation of cell division and expansion. Auxin content rapidly increases after pollination and the manipulation in its levels may lead to the parthenocarpic development. ln Vitis vinifera L., little is known about the early fruit development that encompasses from pollination to fruit set. Pollination/fertilization events trigger fruit formation, and auxin treatment mimics their effect in grape berry set. However, the role of auxin in this process at the molecular level is not well understood. To elucidate the participation of auxin in grapevine fruit formation, morphological, reproductive, and molecular events from anthesis to fruit set were described in sequential days after pollination. Exploratory RNA-seq analysis at four time points from anthesis to fruit set revealed that the highest percentage of genes induced/repressed within the hormone-related gene category were auxin-related genes. Transcript profiling showed significant transcript variations in auxin signaling and homeostasis-related genes during the early fruit development. Indole acetic acid and several auxin metabolites were present during this period. Finally, application of an inhibitor of auxin action reduced cell number and the mesocarp diameter, similarly to unpollinated berries, further confirming the key role of auxin during early berry development. This work sheds light into the molecular features of the initial fruit development and highlights the auxin participation during this stage in grapevine.

Browsing by Author "Arce-Johnson, Patricio"

Results Per Page

Sort Options