Patricio Ramos

Patricio Ramos
Universidad Católica del Maule | UCM · Centro de Investigación de Estudios Avanzados del Maule (CIEAM)

Biochemist, Ph.D.

About

53
Publications
22,053
Reads
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830
Citations
Introduction
My scientific interest is mainly focused on the generation and application of biotechnological knowledge and tools in genomics and biochemistry, mainly in plants and associated microorganisms. To achieve this, it is essential to identify the molecular mechanisms involved in the physiological response to environmental abiotic stresses in plants, and mainly in commercial crops.
Additional affiliations
January 2010 - October 2014
Universidad de Talca
Position
  • PostDoc Position
January 2003 - March 2005
Pontificia Universidad Católica de Chile
Position
  • Research Assistant

Publications

Publications (53)
Article
Full-text available
Strawberry is one of the most widely consumed fruit, but this crop is highly susceptible to drought, a condition strongly associated with climate change, causing economic losses due to the lower product quality. In this context, plant root-associated fungi emerge as a new and novel strategy to improve crop performance under water-deficiency stress....
Article
Full-text available
Calcium is an important second messenger in plants. The activation of Ca2+ signaling cascades is critical in the activation of adaptive processes in response to environmental stimuli. Root colonization by the growth promoting endophyte Serendipita indica involves the increase of cytosolic Ca2+ levels in Arabidopsis thaliana. Here, we investigated t...
Article
Climate change is threatening human activities, but the combination of water scarcity and heat waves are particularly challenging agriculture. Accumulating literature shows that beneficial fungal endophytes improve plant performance, a condition that seems to be magnified in presence of stress. Because evidence points out to an endophytic mediation...
Article
Full-text available
“Let food be thy medicine and medicine be thy food”, is one of the most famous phrases attributed to Hippocrates, the father of medicine. Scientific research on superfoods has increased in the last six years. These foods have nutritional and pharmacological properties, such that they can help to fight against diseases and poor nutritional status. H...
Article
Full-text available
Deschampsia antarctica Desv. (Poaceae) is one of the two vascular plants that have colonized the Antarctic Peninsula, which is usually exposed to extreme environmental conditions. To support these conditions, the plant carries out modifications in its morphology and metabolism, such as modifications to the cell wall. Thus, we performed a comparativ...
Article
Full-text available
Fruit ripening is a process that produces fruit with top sensory qualities that are ideal for consumption. For the plant, the final objective is seed dispersal. One of the fruit characteristics ob- served by consumers is texture, which is related to the ripening and softening of the fruit. Controlled and orchestrated events occur to regulate the ex...
Preprint
Full-text available
Calcium (Ca ) is an important second messenger in plants. The activation of Ca signaling cascades is critical in the activation of adaptive processes in response to perceived environmental stimuli, including biotic stresses. The colonization of roots by the plant growth promoting endophyte Serendipita indica involves the increase of cytosolic Ca le...
Article
Full-text available
Plants reorient the growth of affected organs in response to the loss of gravity vector. In trees, this phenomenon has received special attention due to its importance for the forestry industry of conifer species. Sustainable management is a key factor in improving wood quality. It is of paramount importance to understand the molecular and genetic...
Article
Expansins are proteins involved in cell wall metabolism that play an important role in plant growth, development, fruit ripening and abiotic stress tolerance. In the present study, we analyzed putative expansins that respond to drought stress. Five expansin genes were identified in cDNA libraries isolated from Colobanthus quitensis gown either with...
Article
Full-text available
Approximately thirty percent of the proteins synthesized in animal or plant cells travel through the secretory pathway. Seventy to eighty percent of those proteins are glycosylated. Thus, glycosylation is an important protein modification that is related to many cellular processes, such as differentiation, recognition, development, signal transduct...
Article
Full-text available
Since the intake of fruits and vegetables displays important effects on the incidence of several chronic diseases in humans, consumers' attention worldwide is focused on the identification of functional foods. In this sense, Ugni molinae (murtilla or murta fruit) is an important source of molecules with a strong antioxidant capacity that is widely...
Article
Ground‐level ozone is a global air pollutant with high toxicity and represents a threat to plants and microorganisms. Although beneficial microorganisms can improve host performance, their role in connecting environmentally induced maternal plant phenotypes to progeny [transgenerational effects (TGE)] is unknown. We evaluated fungal endophyte‐media...
Article
Cell wall modification is one of the main factors that produce the tissue softening during ripening of many fruit including strawberry (Fragaria x ananassa). Expansins have been studied for over 20 years as a class of the important cell growth regulators, and in the last years these have been related with the fruit softening. In strawberry, five pa...
Article
Full-text available
Antarctic plants have developed mechanisms to deal with one or more adverse factors which allow them to successfully survive such extreme environment. Certain effective mechanisms to face adverse stress factors can arise from the establishment of functional symbiosis with endophytic fungi. In this work, we explored the role of fungal endophytes on...
Article
Full-text available
Globally, the strawberry is one of the most widely consumed fruits, but under certain environmental conditions, it exhibits inadequate red color development, causing economic losses due to lower product quality. In order to evaluate if changes in color are cultivar-specific and environmentally dependent, a comparative study of anthocyanin accumulat...
Article
Full-text available
Photooxidative stress, when combined with elevated temperatures, triggers various defense mechanisms leading to physiological, biochemical, and morphological changes in fruit tissue. Furthermore, during sun damage, apple fruit undergo textural changes characterized by high flesh firmness compared to unexposed fruit. Fuji and Royal Gala apples were...
Article
Full-text available
Functional symbiosis is considered one of the successful mechanisms by which plants that inhabit extreme environment improve their ability to tolerate different types of stress. One of the most conspicuous type of symbiosis is the endophyticism. This interaction has been noted to play a role in the adaptation of the native vascular plant Colobanthu...
Article
Climate change negatively influences many human activities and one of the most affected is agriculture. In the apple industry, water availability, elevated temperatures and altered phenology will transform fruit production in traditional growing regions. Extended periods of intense solar radiation and high temperatures during the growing season cau...
Article
Full-text available
The molecular mechanisms underlying inclination responses in trees are unclear. In this study, we identified a MADS-box transcription factor differentially expressed early after inclination in the stems of Pinus radiata D. Don. PrMADS10 has a CDS of 582 bp and encodes a group II MADS-box transcription factor. We measured highest accumulation of thi...
Article
Full-text available
The endo-β-1,4-glucanases (EGs) that belonging to the glycosyl hydrolase family 9 (GH9) have roles in cell wall synthesis, remodeling and degradation. Previous studies have suggested that EGs may play a key role in the ripening of different fruits including strawberries. Now, we used qRT-PCR assays to determine the transcript accumulation of an end...
Article
Strawberry is one of the most popular fruits in the world because of its good organoleptic characteristics, as its aroma is a complex characteristic that significantly contributes to fruit quality. In the present work, we performed a comparative study of the differences in the volatile organic compounds (VOCs) contents and the enzymatic activity an...
Article
Since an intake of fruits and vegetables displays important effects on the incidence of several chronic and non-infectious diseases in humans, consumers' attention worldwide is focused on identification of functional foods. In this sense, Fragaria chiloensis ssp. chiloensis f. chiloensis fruit has recently emerged as a preferred berry because of it...
Article
Full-text available
The endo-β-1,4-glucanases (EGs) that belong to the glycosyl hydrolase family 9 (GH9) have roles in cell wall synthesis, remodeling and degradation. Previous studies have suggested that EGs may play a key role in the ripening of different fruits including strawberries. In this study, we used reverse-transcription quantitative polymerase chain reacti...
Article
Full-text available
The response to inclination in plants is an attractive and extensively studied biological process. The most commonly held theory proposes a differential growth in stem tissue due to unequal auxin redistribution. Further evidence proposed that flavonoids act as molecular regulators of auxin distribution or flux. It is well known that flavonoids affe...
Article
Plants respond to the loss of vertical growth re-orientating their affected organs. In trees, this phenomenon has received the scientific attention due to its importance for the forestry industry. Nowadays it is accepted that auxin distribution is involved in the modulation of the tilting response, but how this distribution is controlled is not ful...
Cover Page
Full-text available
In the gravitropic response of radiata pine seedlings, six different transcripts encoding expansins proteins are expressed in a spatio-temporal manner along inclined stem. The deduced proteins display differential affinity to a cellulose polymer, calculated through a bioinformatic approach, suggesting that different expansins expressed could be non...
Article
Changes in the cellulose-hemicellulose fraction take place during ripening of strawberry fruit, and was associated to the activity of a set of proteins and hydrolytic enzymes. Expansins are proteins located in the cell wall with no catalytic activity. In this context, FaEXPA1 was previously reported with high accumulation rate during fruit ripening...
Article
Fruit softening during ripening is mainly a consequence of solubilization and depolymerization of cell wall components mediated by the action of a complex set of enzymes and proteins. In the present work, we performed a comparative study of the changes in physiological properties, cell wall-associated polysaccharide contents and expression of cell...
Article
Antarctic environments are amongst the most stressful habitats for life on Earth, with high intensities of solar UV-B radiation reaching the land surface. In this study, we evaluated how the photochemical efficiency, cell damage and reproductive biomass of Antarctic pearlwort (Colobanthus quitensis) were affected by different intensities of UV-B ra...
Article
Full-text available
The response to inclination in plants is a well-studied biological process where hormones have been implicated in the modulation of vertical growth restoration. Studies on the involvement of auxins in differential growth of plant stems have resulted in the hypothesis that differential growth in stem tissue is due to unequal auxin re-distribution. I...
Article
Full-text available
A comparative study of antioxidant properties, platelet antiaggregation activity and transcriptional analysis of flavonoid biosynthesis genes were performed in Fragaria x ananassa, F. vesca and F. chiloensis subsp chiloensis f. chiloensis and f. patagonica. Furthermore, differences in flavonoid content were found by UHPLC-MS. The highest free radic...
Poster
Full-text available
Expansins are proteins associated to several processes including fruit ripening. Changes in the cellulose-hemicellulose fraction take place during ripening of Fragaria chiloensis and Fragaria ananassa fruits, two species of Fragaria genus with different softening rates. Previously was reported the increase of some expansins transcripts by Northern...
Article
Plants have the ability to reorient their vertical growth when exposed to inclination. This response can be as quick as 2 h in inclined young pine (Pinus radiata D. Don) seedlings, with over accumulation of lignin observed after 9 days s. Several studies have identified expansins involved in cell expansion among other developmental processes in pla...
Article
Full-text available
Abstract Stem reorientation in response to inclination in trees has commanded the attention of the research community widely, but the molecular mechanisms of the response are still unknown. The most accepted theory is auxin redistribution in affected tissues. Flavonols have been reported as potent inhibitors of polar auxin transport; however, no re...
Chapter
Full-text available
Anthocyanins are one of the most abundant flavonoid compounds. These pigments, naturally present in fruits and vegetables, provide color and promote health benefits to consumers due to their antioxidant capacity. To date, more than 600 anthocyanins have been identified in nature, all coming from six anthocyanidin aglycones derived from flavylium ba...
Article
Full-text available
The cell wall is a dynamic structure that can be modified by different conditions during growth. Stem inclina- tion induces biochemical changes and chemical modifications in the cell walls of conifers driving plant stem reorientation. Different enzymes take part in cell wall remodeling, including xyloglucan endotransglycosylase/hydrolase (XTH). Thi...
Article
In conifers, relationship between ethylene and the response to inclination are not well understood. The aim of this work was to study the consequence for the application of 2-chloroethyl phosphonic acid (ethephon), compound able to release ethylene, in one-year-old Pinus radiata D. Don seedlings subjected to inclination. In plants exposed to inclin...
Article
Full-text available
The cuticle is a hydrophobic barrier located at the aerial surface of all terrestrial plants. Recent studies performed on model plants, such as Arabidopsis thaliana, have suggested that the cuticle may be involved in drought stress adaptation, preventing non-stomatal water loss. Although forest trees will face more intense drought stresses (in dura...
Article
Full-text available
In conifers, relationship between ethylene and the response to inclination are not well understood. The aim of this work was to study the consequence for the application of 2-chloroethyl phosphonic acid (ethephon), compound able to release ethylene, in one-year-old Pinus radiata D. Don seedlings subjected to inclination. In plants exposed to inclin...
Article
Full-text available
Loss of verticality in conifers affects the nor-mal wood development by inducing changes and chemical modifications in tree stems called compression wood. It is known that ethylene influences the response during this abnormal wood-forming process. The expression pattern of genes involved in the ethylene biosynthesis pathway during gravitropic respo...
Article
The gravitropic response in trees is a widely studied phenomenon, however understanding of the molecular mechanism involved remains unclear. The purpose of this work was to identify differentially expressed genes in response to inclination using a comparative approach for two conifer species. Young seedlings were subjected to inclination and sample...
Article
Full-text available
Coniferous trees develop compression wood in response to gravitropic stimuli. In nature this response can be generated by growth in slope, exposure to snow or high winds [1]. However, genes and molecular mechanism involved in this phenomenon are still unknown. We studied gene expression in response to gravitropic stimulation induced by 45° inclinat...
Article
Full-text available
Peroxisome proliferator-activated receptor gamma (PPARgamma) has been proposed as a therapeutic target for neurodegenerative diseases because of its anti-inflammatory action in glial cells. However, PPARgamma agonists preventbeta-amyloid (Abeta)-induced neurodegeneration in hippocampal neurons, and PPARgamma is activated by the nerve growth factor...
Article
Full-text available
Peroxisome proliferator-activated receptor (PPAR) has been proposed as a therapeutic target for neurodegenerative diseases because of its anti-inflammatory action in glial cells. However, PPAR agonists prevent-amyloid (A)-induced neurodegenera-tion in hippocampal neurons, and PPAR is activated by the nerve growth factor (NGF) survival pathway, sugg...
Article
Full-text available
Neurotrophins are trophic factors that regulate important neuronal functions. They bind two unrelated receptors, the Trk family of receptor-tyrosine kinases and the p75 neurotrophin receptor (p75). p75 was recently identified as a new substrate for gamma-secretase-mediated intramembrane proteolysis, generating a p75-derived intracellular domain (p7...
Article
Full-text available
Peroxisome proliferator-activated receptor gamma (PPARgamma), a member of the nuclear receptor superfamily, is subject to considerable interest because of its role in adipocyte differentiation, metabolic control, and anti-inflammatory action. PPARgamma research in brain cells is presently focused on glial PPARgamma because of its potential as a pha...
Article
The interaction of parathion, a widely used organophosphorus insecticide, with cell membranes of the isolated toad skin, human erythrocytes, and membrane molecular models is described. The latter consisted of multilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) and large unilamellar vesicles (LUV) of D...
Conference Paper
Loss of verticality in conifers affects the normal wood development by inducing changes and chemical modifications in tree stems. Ethylene influences the response during this abnormal wood-forming process, and expression pattern of genes involved in the ethylene biosynthesis pathway due to inclination in gymnosperm has been reported in adult trees....

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Projects (4)
Project
https://www.mdpi.com/journal/plants/special_issues/NMXM1RLX43 Dear Colleagues, Plants have associations with various beneficial soil microbes, which play important roles in plant growth promotion and resistance against abiotic and biotic stress, including herbivores. The use of these symbiotic microorganisms seems to be a promising alternative control of herbivorous pests in commercial crops. Beneficial soil microbes may enhance defensive mechanisms by which crops may deter herbivore feeding. These beneficial microbes may modulate phytohormone signaling, such as the jasmonic acid, ethylene and salicylic acid pathways, defensive gene expression, synthesis of toxic secondary metabolites, volatile organic compounds, and plant defensive proteins. The main goal of this Special Issue is to bring together current findings on the influence of microbes in crops’ resistance to biotic stress, with a particular emphasis on how the soil microbiota can activate molecular, physiological, and chemical plant defenses against herbivorous pests. Dr. Marcia González-Teuber Dr. Patricio Ramos Guest Editors https://www.mdpi.com/journal/plants/special_issues/NMXM1RLX43
Project
https://www.frontiersin.org/research-topics/46160/revisiting-the-limits-of-plant-life---plant-adaptations-to-extreme-terrestrial-environments-relating Continued discoveries of remarkable plant adaptations to extreme environments challenge our thinking about the limits of plant life. Plants thrive on glaciers, in Antarctic permafrost, and in scorching deserts. Some grow completely submerged in water while others succeed in arid environments. Plants inhabit the ocean twilight zone under crashing pressure and the 6500m elevation on Mount Everest where the atmospheric pressure drops to 44 kPa. Some plants adapted to sustain high UVB photon levels, others colonize ground zero zones with elevated ionizing particle levels of nuclear plant accident sites, atomic bomb test sites, or radioactive element-rich regions. Astoundingly, plants can even physiologically adapt to growing in environments outside of their evolutionary experience such as the spaceflight microgravity and nullification of any physical reference to the gravity vector. Understanding the connection between plant adaptive strategies and their environment, particularly from the edges of the terrestrial plant life, will advance our astrobiology-related efforts in the search for plant biosignatures on exoplanets, moons, or other celestial bodies in the universe, as well as our space biology-related efforts concentrated on incorporating plants into human space exploration missions. Therefore, the goal of this Research Topic is to consolidate the existing knowledge, to present novel plant adaptive strategies to colonize hostile terrestrial habitats, and to present novel discoveries of plant responses to environments outside of plant evolutionary experience. Guiding questions related to this effort include but are not limited to: What are plant strategies to survive in low atmospheric pressure exerted by thin planetary atmospheres? How can plants sustain the particulate ionizing radiation of astrophysical origin in deep space? Are there any molecular solutions to plant photosynthesis outside of the visible light spectrum? What are plant strategies to survive shortage of liquid water? How do plants sense and respond to transitions between gravitational environments? Amassed information will revisit our understanding of the limits of plant life. It will contribute to developing hypotheses regarding the conditions required to sustain plant vegetation on exoplanets. It will also advance designing strategies for genetic manipulations to engineer plant genotypes better suited for human space exploration. We invite submissions of original research, short communications, reviews, mini reviews, opinions, and hypotheses. We wish to assemble a collection of studies on genetic, morphological, physiological, and biochemical strategies of plants pushing the limits of plant life. Analysis of plants from environments of high solar irradiance, high ionizing radiation, and high-altitude mountainous regions are particularly encouraged as well as from polar regions, glaciers, and deserts. Discoveries from space analog environments on Earth or simulated deep space-like environments and terrestrial analog missions are equally welcome. We recommend empirical research based on field observations, laboratory, or chamber experiments and elucidating mechanisms at molecular, cellular, or organism levels. We strongly encourage submissions of the omics data analysis across plant species from the same environment, and same species from different extreme environments. We are also highly interested in reviews summarizing the current knowledge in the context of developing concepts for transformative research relating to astrobiology and space biology. Please note that purely descriptive studies will not be considered.