Browsing by Author "Moreno, Adrian A."

Now showing 1 - 4 of 4
  • No Thumbnail Available
    Item
    Cistanthe longiscapa exhibits ecophysiological and molecular adaptations to the arid environments of the Atacama Desert
    (OXFORD UNIV PRESS INC, 2025) Ossa, Paulina; Moreno, Adrian A.; Orellana, Daniela; Toro, Monica; Carrasco Valenzuela, Tomas; Riveros, Anibal; Meneses Araya, Claudio Antonio; Nilo Poyanco, Ricardo; Orellana, Ariel
    Understanding how plants survive extreme conditions is essential to breeding resilient crops. Cistanthe longiscapa, which flourishes in the Atacama Desert, provides a rare glimpse into plant resilience. To uncover the genetic basis of its stress tolerance, we investigated the ecophysiological and transcriptomic responses of C. longiscapa from 3 sites with low but different precipitation levels. Ecophysiological analyses were performed on samples collected in the field at dusk and dawn, which are crucial stages in crassulacean acid metabolism (CAM), a water-efficient type of photosynthesis. Additional transcriptomic analysis allowed us to evaluate CAM intensity in C. longiscapa and identify changes in the molecular signature of these plants. Our results show that C. longiscapa displays considerable ecophysiological trait response variation across the 3 sites, including variations in markers such as nocturnal acid accumulation, isotopic carbon ratio, and succulence, among others. Analysis of gene expression patterns revealed differences among plants exhibiting varying intensities of CAM photosynthesis and identified key molecular signatures associated with their ecological strategies. Additionally, genes related to stress responses, plastid activities, and circadian rhythm show contrasting expression levels between strong and weak CAM plants, and this expression profile is shared with other CAM plants under stress. Our findings demonstrate that C. longiscapa is a valuable resource for identifying genes involved in the transition between different CAM intensities. This may lead to the discovery of genes that enhance plant tolerance to stressful environments., Cistanthe longiscapa exhibits weak or strong CAM photosynthesis under varying aridity levels in the Atacama Desert, which is associated with contrasting gene expression patterns during dawn and dusk.
  • No Thumbnail Available
    Item
    Metabolite Profiling Reveals the Effect of Cold Storage on Primary Metabolism in Nectarine Varieties with Contrasting Mealiness
    (2023) Olmedo, Patricio; Zepeda, Baltasar; Delgado-Rioseco, Joaquin; Leiva, Carol; Moreno, Adrian A.; Sagredo, Karen; Blanco-Herrera, Francisca; Pedreschi, Romina; Infante, Rodrigo; Meneses, Claudio; Campos-Vargas, Reinaldo
    Chilling injury is a physiological disorder caused by cold storage in peaches and nectarines. The main symptom of chilling injury is mealiness/wooliness, described as a lack of juice in fruit flesh. In this work, we studied two nectarine varieties (Andes Nec-2 and Andes Nec-3) with contrasting susceptibility to mealiness after cold storage. A non-targeted metabolomic analysis was conducted by GC-MS to understand if changes in metabolite abundance are associated with nectarine mealiness induced by cold storage. Multivariate analyses indicated that in unripe nectarines, cold storage promoted a higher accumulation of amino acids in both varieties. Interestingly, for ripe nectarines, cold storage induced an accumulation of fewer amino acids in both varieties and showed an increased abundance of sugars and organic acids. A pathway reconstruction of primary metabolism revealed that in ripe nectarines, cold storage disrupted metabolite abundance in sugar metabolism and the TCA cycle, leading to a differential accumulation of amino acids, organic acids, and sugars in mealy and juicy nectarines.
  • No Thumbnail Available
    Item
    Metabolomic and biochemical analysis of mesocarp tissues from table grape berries with contrasting firmness reveals cell wall modifications associated to harvest and cold storage
    (2022) Balic, Ivan; Olmedo, Patricio; Zepeda, Baltasar; Rojas, Barbara; Ejsmentewicz, Troy; Barros, Miriam; Aguayo, Daniel; Moreno, Adrian A.; Pedreschi, Romina; Meneses, Claudio; Campos-Vargas, Reinaldo
    Tissue texture influences the grape berry consumers acceptance. We studied the biological differences between the inner and outer mesocarp tissues in hard and soft berries of table grapes cv NN107. Texture analysis revealed lower levels of firmness in the inner mesocarp as compared with the outer tissue. HPAEC-PAD analysis showed an increased abundance of cell wall monosaccharides in the inner mesocarp of harder berries at harvest. Immunohistochemical analysis displayed differences in homogalacturonan methylesterification and cell wall calcium between soft and hard berries. This last finding correlated with a differential abundance of calcium measured in the alcohol-insoluble residues (AIR) of the inner tissue of the hard berries. Analysis of abundance of polar metabolites suggested changes in cell wall carbon supply precursors, providing new clues in the identification of the biochemical factors that define the texture of the mesocarp of grape berries.
  • Thumbnail Image
    Item
    Two antagonistic gene regulatory networks drive Arabidopsis root hair growth at low temperature linked to a low-nutrient environment
    (WILEY, 2025) Urzúa Lehuede, Tomás; Berdion Gabarain, Victoria; Ibeas, Miguel Angel; Salinas Grenet, Hernán; Achá Escobar, Romina; Moyano, Tomás C.; Ferrero, Lucía; Núñez Lillo, Gerardo; Pérez Díaz, Jorge; Perotti, María Florencia; Natali Miguel, Virginia; Spies, Fiorella Paola; Rosas, Miguel A.; Kawamura, Ayako; Rodríguez García, Diana R.; Kim, Ah-Ram; Nolan, Trevor; Moreno, Adrian A.; Sugimoto, Keiko; Perrimon, Norbert; Sanguinet, Karen A.; Meneses Araya, Claudio Antonio; Chan, Raquel L.; Ariel, Federico; Alvárez, José M.; Estévez, José M.
    Root hair (RH) cells can elongate to several hundred times their initial size, and are an ideal model system for investigating cell size control. Their development is influenced by both endogenous and external signals, which are combined to form an integrative response. Surprisingly, a low-temperature condition of 10 degrees C causes increased RH growth in Arabidopsis and in several monocots, even when the development of the rest of the plant is halted. Previously, we demonstrated a strong correlation between RH growth response and a significant decrease in nutrient availability in the growth medium under low-temperature conditions. However, the molecular basis responsible for receiving and transmitting signals related to the availability of nutrients in the soil, and their relation to plant development, remain largely unknown. We have discovered two antagonic gene regulatory networks (GRNs) controlling RH early transcriptome responses to low temperature. One GNR enhances RH growth and it is commanded by the transcription factors (TFs) ROOT HAIR DEFECTIVE 6 (RHD6), HAIR DEFECTIVE 6-LIKE 2 and 4 (RSL2-RSL4) and a member of the homeodomain leucine zipper (HD-Zip I) group I 16 (AtHB16). On the other hand, a second GRN was identified as a negative regulator of RH growth at low temperature and it is composed by the trihelix TF GT2-LIKE1 (GTL1) and the associated DF1, a previously unidentified MYB-like TF (AT2G01060) and several members of HD-Zip I group (AtHB3, AtHB13, AtHB20, AtHB23). Functional analysis of both GRNs highlights a complex regulation of RH growth response to low temperature, and more importantly, these discoveries enhance our comprehension of how plants synchronize RH growth in response to variations in temperature at the cellular level.